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In 2012, the number of people arrested in the U.S. for felonies and misdemeanors was around 12.2 million.1
That’s a lot of arrests. And all of them were made by officers who thought they had probable cause. Some were mistaken.
While some false arrests are inexcusable, most are made in good faith as the result of a slight defect in the concept of probable cause: Nobody really knows what it means. In fact, even the United States Supreme Court described it as something that is both “elusive” and “abstract,”2 two words that would ordinarily be used to describe such unintelligible concepts as the meaning of life and Einstein’s Theory of Relativity. But unlike philosophers and physicists who have years (or lifetimes) to ponder the questions before them, officers must often reach their conclusions on-the-spot, and may have to do so based on information that is disordered, incomplete, or conflicting. Plus their information often comes from sources whose motives and reliability are unknown or questionable.3
So unless probable cause happens to be an easy call, or unless officers have the luxury of conducting further investigation or waiting for an arrest warrant, they must try to make the correct decision based on whatever information is at hand and whatever inferences and conclusions they can draw from it.4 This necessarily requires an understanding of the basic principles of probable cause and how to determine the reliability of the various sources of information. Both of these subjects were covered in articles in the Spring-Summer 2014 -, both of which can be downloaded at le.alcoda.org.
In this article, we will focus on probable cause to arrest and the related subject of reasonable suspicion to detain. (We will cover probable cause to search in the Winter 2015 edition.) At first glance, this subject might seem simple because most of the relevant circumstances pertaining are fairly obvious. But it can be a challenge to keep track of—and especially recall—every major and minor incriminating circumstance that comes to light in the course of an investigation, whether it’s a short investigation by a patrol officer on the street or a lengthy investigation by teams of detectives. And recalling incriminating circumstances is crucial because, as we discussed in the Spring-Summer edition, with each additional piece of incriminating evidence that an officer can testify to, the odds of having probable cause and reasonable suspicion increase exponentially.
To illustrate, if probable cause could be tallied on a court-approved scorecard, and if an officer who carried one around saw a pedestrian who matched the general description of the perpetrator of a robbery that had just occurred down the street, he would give the suspect a PC score of, say, two: one point for resembling the robber and a second point for being near the crime scene shortly after the holdup. But he would also give the suspect a bonus point because the combination of the two independent circumstances is, in effect, an additional incriminating circumstance in that it constitutes a “coincidence of information.”5 And if there were a third or fourth independent incriminating circumstance, the score starts climbing through the roof. In other words, when it comes to probable cause, the whole is much greater than the sum of its parts.
Another advantage of being able to catalogue the relevant circumstances is that it becomes easier to present the facts logically and persuasively in a declaration of probable cause, an arrest warrant affidavit, in testimony at a suppression hearing, or during an internal affairs investigation.
One other thing: Most of these circumstances we will cover are relevant in establishing both probable cause to arrest and reasonable suspicion to detain. The only difference is that probable cause requires information of higher quality and quantity than reasonable suspicion. Again, this subject was covered at length in the Spring-Summer edition.
Description Similarities
When a witness sees the perpetrator of a crime but does not know him, probable cause will frequently be based, at least in part, on physical similarities between the perpetrator and suspect, their clothing, or their vehicles. And, of course, any similarity becomes much more significant if there was something unique or unusual about it; e.g., a distinctive tattoo or scar.6 As the Court of Appeal observed, “Uniqueness of the points of comparison must also be considered in testing whether the description would be inapplicable to a great many others.”7
PHYSICAL APPEARANCE
Each individual physical similarity between the perpetrator and suspect— height, weight, build, age, race, hair color—has little significance. In other words, neither a “mere resemblance” to the perpetrator nor a resemblance to a “vague” physical description will carry much weight, even for an investigative detention.8 Instead, what matters—and it matters a lot— is the number of independent corresponding characteristics.9
CLOTHING
Similar or matching clothing or other attire is highly relevant especially if the crime occurred so recently that it was unlikely that the perpetrator had time to change clothes.10 And, of course, multiple similarities in the clothing and the manner in which they were worn are also important; e.g., red 49er baseball cap worn backwards.11
VEHICLE SIMILARITIES
If a vehicle was used in the commission of the crime, each similarity between the perpetrator’s and suspect’s vehicles is necessarily significant; e.g., similar license plate numbers,12 both vehicles were very old,13 both were light colored compact station wagons.14 And these similarities become even more important if there was some additional independent reason to connect the vehicle to the crime; e.g., an occupant resembled the perpetrator, the car was spotted near the crime scene, the occupants acted in a suspicious manner.15
CORRESPONDING NUMBER OF PEOPLE
If there were two or more perpetrators, it is significant that officers detained a group of suspects shortly after the crime was committed and the number of suspects corresponded with the number of perpetrators.16
DISCREPANCIES
The courts understand that witnesses may inadvertently provide officers with descriptions of perpetrators and vehicles that are not entirely accurate. Thus, officers may make allowances for the types of errors they have come to expect.17 As the Court of Appeal observed, “Crime victims often have limited opportunity for observation; their reports may be hurried, perhaps garbled by fright or shock.”18 For example, the following discrepancies in vehicle descriptions were considered insignificant:
• The perpetrator’s license plate number 127AOQ was reported as 107AOQ.19
• Yellow 1959 Cadillac, license number XQC 335 was described as a yellow 1958 or 1959 Cadillac with partial plate of OCX.20
• Tan over brown 1970 Oldsmobile, license 276AFB, was described as a 1965 Oldsmobile or Pontiac, license 276ABA.21
• A black-over-gold Cadillac was described as a light brown vehicle, possibly a Chevrolet.22
Three other things about discrepancies: First, the courts are not so forgiving when the error was made by an officer instead of a witness. As the Court of Appeal explained, “While officers should not be held to absolute accuracy of detail in remembering the numerous crime dispatches broadcast over police radio . . . [a]n investigative detention premised upon an officer’s materially distorted recollection of the true suspect description is [unlawful].”23
Second, if the crime had just occurred, and if officers detained a group of suspects, the fact that the number of people in the group was larger or smaller than the number of perpetrators is not considered a significant discrepancy. This is because, as the California Court of Appeal observed in a robbery case, “it is a matter of common knowledge that holdup gangs often operate in varying numbers and combinations, and the victim of a robbery does not always see all of the participants.”24 Third, even if witnesses did not see a getaway car, officers may usually infer that one was used. Thus, if the suspect was in a vehicle when he was detained or arrested, the fact that witnesses did not see a vehicle will not ordinarily constitute a discrepancy.25
Suspect’s Location
While probable cause may often be based largely on a suspect’s presence in a certain house, car, or other private place, officers may not ordinarily arrest or detain a person merely because he was present in a place that was open to the public.26 Still, the suspect’s presence at a public location is often highly relevant.27 And it may become critical if there was some independent circumstantial evidence of his involvement in a crime, such as a similar physical, clothing, or vehicle description, or any of the various suspicious circumstances we will discuss later. Also note that if the suspect’s presence in a certain location was incriminating, it is significant that there were few, if any, other people in the area because, for example, it was late at night or early in the morning.28
NEAR THE CRIME SCENE
A suspect’s presence at or near the scene of a crime—whether before, during, or just after the crime occurred—is of course a relevant circumstance. And, thanks to modern technology, this circumstance is becoming increasingly important as officers are often able to determine the suspect’s whereabouts at a particular time by means of GPS tracking or cell tower triangulation.29
ON ACTUAL ESCAPE ROUTE
If a witness reported that he saw the perpetrator flee on a certain street, it would be of major importance that officers saw the suspect on that street or on an artery at a time and distance consistent with flight by the perpetrator.30
ON A LOGICAL ESCAPE ROUTE
Officers may be able to predict a perpetrator’s escape route based on their knowledge of traffic patterns in the area. If so, it would be significant that the suspect was traveling along a logical escape route if his distance from the crime scene and the elapsed time were consistent with flight by the perpetrator. Examples:
• At about 4 A.M., two men robbed a gas station in Long Beach. Two officers “proceeded to a nearby intersection, a vantage point which permitted them to survey the street leading from the crime scene to a freeway entrance, a logical escape route.” A few minutes later, they saw two men in a car; the men fit the description of the robbers. No other cars were in the area; the suspects were “excessively attentive to the officers.”31
• Shortly after a gang-related drive-by murder, LAPD officers found the shooters’ car abandoned, and they reasonably believed the occupants had fled on foot. An officer assigned to a gang unit figured the shooters would be heading to their own neighborhood “by a route which avoided the territories of rival and hostile gangs,” and he knew their “most logical route.” Along that route, he detained several young men who were wearing the colors of the perpetrators’ gang.32
• At about 8 P.M., two men robbed a motel in Coronado, an island in San Diego Bay with only two bridges leading in and out. Police dispatch transmitted a very general description of the suspects but no vehicle description. Within minutes, an officer at one of the bridges saw a car occupied by two men who matched the general description. Two other men in the car ducked down when the officer started following them.33
HIGH CRIME AREA
A suspect’s presence in a “high crime area” is virtually irrelevant.34 “It is true, unfortunately,” said the Court of Appeal, “that today it may be fairly said that our entire nation is a high crime area where narcotic activity is prevalent. Therefore, such factors, standing alone, are not sufficient to justify interference with an otherwise innocent-appearing citizen.”35 It is, however, a circumstance that may become relevant in light of other circumstances,36 especially if officers or witnesses saw the suspect engage in conduct that is associated with the type of criminal activity that is prevalent in the area.
For example, in In re Michael S.37 the court upheld the detention of a suspected auto burglar mainly because he was in an area in which officers had received “many complaints” of vehicle tampering, and the officers saw him “secreted or standing between two parked cars, looking first into one and then into the other as if examining them.” (As for hand-to-hand transactions in high crime areas, see “Suspicious Activity” (High crime area), below.)
INSIDE A PERIMETER
A suspect’s presence inside a police perimeter is significant, especially if the perimeter was fairly tight and was set up quickly after the crime occurred. For example, in People v. Rivera 38 the court ruled that an officer had probable cause to arrest two men suspected of having just broken into an ATM because, among other things, he “knew that 10 surveillance units and at least 10 other patrol cars, with their lights f lashing, had formed a perimeter to contain the suspects.”
Reaction to Seeing Officers
Even if they are not doing anything illegal at the moment, criminals tend to become nervous when they see an officer or patrol car. So officers naturally view this as a suspicious circumstance. And so do the courts—but with two qualifications: First, the officers must have had reason to believe the suspect had seen and recognized them. Second, the nature of the reaction must have been sufficiently suspicious.
Proving recognition
As noted, a suspect’s reaction to seeing officers can be deemed suspicious only if it reasonably appeared he had recognized them as officers. As the Court of Appeal explained, “Absent a showing the citizen should reasonably know that those who are approaching are law enforcement officers, no reasonable inference of criminal conduct may be drawn.”39 In most cases, this requirement is easily satisfied if (1) the reaction occurred immediately after the suspect looked in the officers’ direction; and (2) the officers were in a marked patrol car or were wearing a standard uniform or other clearly identifiable departmental attire. But if the officers were in plain clothes or in an unmarked car, the relevance of the suspect’s reaction will depend on whether there was some circumstantial evidence of recognition. Thus, in People v. Huntsman 40 the court ruled that the defendant’s flight from officers was not incriminating because the officers “were in plain clothes and were driving an unmarked car at night.”
In addition to marked cars, there are semi-marked vehicles; i.e., vehicles with enough exposed police equipment or other markings that most people— especially criminals—will easily spot them. As the Court of Appeal put it, some of these cars are “about as inconspicuous as three bull elephants in a backyard swimming pool.”41 Still, when this issue arises at a hearing on a motion to suppress evidence, officers must be able to prove that they reasonably believed the defendant had identified them or their car. This might be accomplished by describing in detail the various police markings and equipment that were readily visible. Thus, in U.S. v. Nash the court ruled that an officer’s vehicle was clearly identifiable mainly because it was “a dark blue Dodge equipped with several antennae and police lights on the rear shelf.”42
Suspicious reactions
Assuming that the officers reasonably believed the suspect had recognized them, the significance of his reaction will depend on the extent to which it indicated alarm or fear.43 The following reactions are especially noteworthy.
FLIGHT
Running from an officer is one of the strongest nonverbal admissions of guilt a person can make. In the words of the Supreme Court, flight is “the consummate act of evasion; it is not necessarily indicative of wrongdoing, but it is certainly suggestive of such.”44 Nevertheless, the Court ruled that flight will not automatically establish grounds to detain. Instead, there must have been least one additional suspicious circumstance; i.e., “flight plus.”45 For example, the courts have ruled that the following additional circumstances were sufficient to establish grounds to detain:
• Flight in a high-crime area.46
• Flight in the early morning hours.47
• Flight from near a crime scene.48
• Flight after having been observed hiding.49
• Flight after making a hand-to-hand transaction in high-drug area.50
• Flight after making a gesture as if to retrieve a weapon or discard evidence.51
• Flight plus matching a general description of a wanted suspect.52
Note that if officers already have grounds to detain the suspect, his flight may convert reasonable suspicion into probable cause to arrest, or at least provide grounds to arrest him for obstructing an officer in the performance of his duties.53
ATTEMPTING TO HIDE FROM OFFICERS
Like flight, a person’s attempt to hide from officers—including “slouching, crouching, or any other arguably evasive movement”54—is a highly suspicious circumstance.55 Here are some examples:
• Upon seeing the officers, a young man standing between two parked cars in an alley “stepped behind a large dumpster and then continued to move around it in such a fashion that he blocked himself from the officers’ view.”56
• Officers saw the suspect hide behind a fence and peer out toward the street.57
• When their parked car was spotlighted by an officer, two people in the front seat “immediately bent down toward the floorboard.”58
ATTEMPTING TO AVOID OFFICERS
Although not as suspicious as an obvious attempt to hide, it is relevant that, upon observing officers, the suspect attempted to avoid them by, for example, walking away or quickly changing direction. As the Third Circuit observed, although walking away from officers “hardly amounts to headlong flight,” it is “a factor that can be considered in the totality of the circumstances.”59 Some examples:
• Suspects “suddenly changed course” and “increased their pace” as the officers’ vehicle came into view.60
• Suspects split up.”61
• At 4 A.M., as officers arrived at a business in which a silent burglary alarm had been triggered, a man standing next to the business walked away.62
• As a murder suspect drove up to his girlfriend’s house and started to pull into the driveway, he saw that sheriff ’s deputies were there, at which point he backed up and drove off. 63
• When a driver saw a patrol car late at night, he “accelerated his vehicle and made two quick turns and an abrupt stop, hurriedly dousing his auto lights.”64
• When a man who was suspected of selling drugs to a passing motorist saw an officer, he “abruptly withdrew from the [buyer’s] car window” and the driver of the car drove off.65
WARNING TO ACCOMPLICE
If two or more suspects were standing together when one of them apparently spotted an officer, his immediate warning to the other is considered highly suspicious; e.g., “Jesus Christ, the cops,”66 “Oh shit. Don’t say anything,”67 “Police!”68 “Rollers!”69 “The man is across the street.”70 Exclamations such as these naturally become even more suspicious if there was an immediate avoidance response; e.g., “Let’s get out of here,”71 “Bobby, Bobby, run, it’s the narcs.”72
SUDDEN REACH: Any sudden—almost instinctive— reaching into a pocket or other container or place upon seeing an officer is highly suspicious because of the possibility that the suspect is reaching for a weapon or disposable evidence. The following are examples that have been noted by the courts:
• When a suspected drug dealer saw a patrol car, he suddenly put his hand inside his jacket.73
• The suspect “put his hands in his pockets and started ‘digging’ in them.”74
• The suspect made “a sudden gesture with his right hand to his left T-shirt pocket.”75
• “Just after [the officer] started the search around defendant’s waistband, defendant abruptly grabbed for his outside upper jacket pocket.”76
• The suspect “reached towards the front of his pants several times.”77
• The suspect “shoved his hand into his right trouser pocket quite rapidly.”78
ATTEMPT TO HIDE, CONCEAL, OR DISCARD
An apparent attempt to hide an unknown object upon seeing an officer is certainly suspicious because it is usually reasonable to infer that the item was a weapon, contraband, or other evidence of a crime.79 Although such an attempt is especially relevant if officers could see that there was, in fact, an object of some sort that the suspect was attempting to conceal, the important thing is that the suspect’s actions were reasonably interpreted as such.
The following are examples of actions that reasonably indicated the suspect was attempting to hide, conceal, or discard something:
• As officers approached a car they had stopped, they saw the driver “pushing a white box under the front seat.”80
• The officers saw appellant “reach into the back of his waistband and secrete in his hands an object which he had retrieved.”81
• Upon seeing officers, the suspect “threw a small plastic bag onto the ground.”82
• The suspect “was holding his hands clasped together in front of a bulge in the waistband in the middle of his waist.”83
• After officers lit up the car, the backseat passenger started moving around and looked back several times at the patrol car.84
• Upon seeing the officers, the suspect quickly made a “hand-to-mouth movement, as though secreting drugs.”85
• A suspected drug dealer sitting inside his car kept his left hand hidden from the officer who had detained him.86
• As the suspect was looking in her purse for ID, she “attempted to obstruct [the officer’s] view.”87
EXTREME ATTENTION TO OFFICERS
A person’s extreme or unusual attention to officers may be noteworthy, especially if accompanied by some physical response and if officers could provide detailed testimony as to what the suspect did and why it appeared suspicious. Here are some examples:
• Defendant was “constantly checking the [rear view] mirrors and talking on his mobile phone as he looked back at the unmarked car behind them.”88
• Upon seeing a police car, the suspect “did not give it the passing glance of the upright, law abiding citizen. His eyes were glued on that car.”89
• The suspect “appeared to be startled by [the officer], had a ‘look of fear in his eyes’ and then quickly looked away.”90
• All six suspects inside a moving vehicle turned to look at an officer as they drove past him.91
Instead of paying inordinate attention to officers, a suspect will sometimes pretend that he didn’t see them. This, too, can be relevant, especially if officers can explain why it appeared to be a ploy. For example, in U.S. v. Arvizu the Supreme Court ruled it was somewhat suspicious that a driver, as he passed a patrol car, “appeared stiff and his posture very rigid. He did not look at [the officer] and seemed to be trying to pretend that [the officer] was not there.”92
Suspicious Activities
Officers sometimes see people doing things that, although not illegal, are suspicious or at least consistent with criminal activity.93 While such conduct will seldom constitute probable cause to arrest, it is frequently sufficient for a detention.94 However, the extent to which an activity can reasonably be deemed “suspicious” will often depend on the officer’s training and experience and the setting in which it occurred; e.g., the time of day or night, the location, and anything else that adds color or meaning to it. As the Court of Appeal observed, “Running down a street is in itself indistinguishable from the action of a citizen engaged in a program of physical fitness. Viewed in context of immediately preceding gunshots, it is highly suspicious.”95
EXCESSIVE ALERTNESS
Before, during, and after committing a crime, people instinctively tend to look around a lot to see if anyone is watching. This is especially true of robbers, burglars, and people who sell or buy drugs on the street. As the Court of Appeal noted, “Those involved in the narcotics trade are a skittish group—literally hunted animals to whom everyone is an enemy until proven to the contrary.”96 Here are some examples of suspicious alertness:
• As a suspected drug purchaser left a drug house, he quickly looked “side to side.”97
• A suspected drug dealer “scouted the area before entering the apartment.”98
• A suspected drug dealer “loitered about and looked furtively in all directions.”99
• A suspected burglar “alighted from the vehicle and looked around apprehensively for quite some period of time.”100
• Two men leaving a jewelry store (after robbing it) kept looking back at the store.101
COUNTERSURVEILLANCE
Another common and suspicious activity of paranoic or merely vigilant criminals is counter surveillance walking or driving, which generally consists of tactics that make it difficult for officers to follow them or at least force the officers to engage in conspicuous surveillance. Here are some examples of counter surveillance driving by suspected drug traffickers:
• Suspect began “weaving in and out of traffic at a high rate of speed in an apparent attempt to evade surveillance.”102
• Suspect went to two houses “which the officers associated with drugs, and drove in and out of the parking lots of those buildings several times.”103
• Suspect would “make U-turns in the middle of streets, slow down at green lights, and then accelerate through intersections when the lights turned yellow.”104
• Suspect “pulled to the curb, allowing a surveillance unit to pass [then] drove to a residence after first going past it and making a U-turn.”105
• Suspect drove “up and down side streets, making numerous U-turns, stopping, backing up, and finally arriving at the Ganesha Street property.”106
LATE NIGHT ACTIVITY
Some crimes are typically committed late at night when there are usually fewer potential witnesses; e.g., robberies, commercial burglaries. Consequently, the time of night in which an activity occurred can add meaning to it. Examples:
• 11:40 P.M.: Officer saw three people inside a car parked “in front of a darkened home” in a neighborhood in which two to three burglaries had been occurring each week.107
• Midnight: Officer saw two occupied cars parked behind the sheriff ’s warehouse; there were no homes or places of business in the area.108
• Midnight: On a dark and secluded road, an officer saw an occupied pickup truck “nosed into the driveway of a fenced construction storage area,” and there was a big box in the back of the truck.109
• 12:15 A.M.: Officers saw two men “peering” into the window of a closed radio shop”; when the men saw the officers, they started to walk away.110
• 2:30 A.M.: Officers saw “three people in a car driving around a high crime area” and “the car proceeded along two residential blocks, slowing intermittently in a manner that an observing officer thought consistent with preparing for a burglary or drive-by shooting.”111
• 2:35 A.M.: Officer saw a man “exiting from darkened private property where valuable merchandise was located.”112
• 3:30 A.M.: Two men who were walking in a business area started running when they saw a patrol car approaching.113
CASING
Conduct that is indicative of casing a location for a crime (typically robbery or burglary) is, of course, highly suspicious. In fact, such conduct resulted in one of the most important cases in criminal law: Terry v. Ohio.114 In Terry, an officer noticed two men standing together in downtown Cleveland, Ohio at about 2:30 P.M. As the officer watched, he noticed one of the men walk over to a nearby store and look in the window. The man then “rejoined his companion at the corner, and the two conferred briefly. Then the second man went through the same series of motions.” The two men “repeated this ritual alternately between five and six times apiece—in all, roughly a dozen trips.” At this point, the officer detained the men because, as he testified, he suspected they were “casing a job, a stick-up” and that he “considered it his duty” to investigate. The U.S. Supreme Court agreed that the men’s conduct warranted a detention.
HAND-TO-HAND EXCHANGES
Hand-to-hand exchanges are common occurrences and are therefore not, in and of themselves, suspicious.115 But they can easily become so depending on a combination of surrounding circumstances, such as:
NATURE OF ITEM EXCHANGED
The object of the exchange looked like illegal drugs; e.g., “two small, thin, white, filterless cigarettes.”116
PACKAGING OF ITEM EXCHANGED
The object was packaged in a manner consistent with drug packaging; e.g., a baggie,117 a “flat waxed paper package of the size and appearance used for the sale of marijuana in small quantities.”118
LOCATION OF TRANSACTION
The transaction occurred in an area where street sales of drugs, stolen property, or weapons commonly occur.119
MONEY EXCHANGE
The suspected buyer gave money to the suspected seller.120
FURTIVENESS
The parties acted in a manner indicating they did not want to be seen; e.g., seller “looked about furtively,”121 seller “walked over to an apparent hiding place before and after the exchange,”122 the buyer hid the object of the transaction in a cigarette case which he then placed in his pocket,”123 when the parties saw an approaching police car “their conversation ceased and their hands went into their pockets very rapidly.”124
PANICKY REACTION TO OFFICERS
Upon observing the officers, one or both of the suspects displayed signs of panic. This subject was covered in the section “Reaction to Seeing Officers,” above.
MULTIPLE EXCHANGES
The apparent seller engaged in several such transactions with various buyers.125
PRIOR ARRESTS
The seller or buyer had prior arrests for selling or possessing contraband.126
ADVANCING ON OFFICERS
A suspect’s act of quickly approaching officers who are about to contact or detain him is a suspicious (and worrisome) response. Thus, in People v. Hubbard the following testimony by an officer established reasonable suspicion for a pat search: “Like I said, all three suspects alighted from the vehicle almost simultaneously. They all got out on us.”127 Similarly, U.S. v. Mattarolo, the court upheld a pat search because “[t]he defendant’s swift approach caused the officer to get out of his squad car quickly so as not to be trapped with the means of protecting himself consequently limited.”128
“UNUSUAL” ACTIVITY
A detention may be based, at least in part, on activity that is “so unusual, so far removed from everyday experience that it cries out for investigation,” even if “there is no specific crime to which it seems to relate.”129
Nervousness
Although a suspect’s nervousness upon being contacted or detained is a relevant factor,130 its significance usually depends on whether it was extreme or unusual.131 The following fall into that category:
• The suspect’s “neck started to visibly throb.”132
• “[V]isibly elevated heart rate, shallow breathing, and repetitive gesticulations, such as wiping his face and scratching his head.”133
• “[P]erspiring and shaking.”134
• “[P]erspiring, swallowing and breathing heavily, and constantly moving his feet or fingers.”135
Although less significant, the following indications of nervousness have been noted: suspect looked “shocked,”136 suspect appeared “nervous and anxious to leave the area,”137 and suspect appeared nervous and was hesitant in answering questions.138 Much less significant—but not irrelevant 139—is a suspect’s failure to make eye contact with officers.140
Lies and Evasions
When a suspect lies, evades a question, gives conflicting statements or tells an unbelievable story it is ordinarily reasonable to infer that the truth would incriminate him.141 Consequently, the following are all suspicious circumstances:
MATERIAL LIES
The most incriminating lie is one that pertains to a material issue of guilt.142 Said the court in People v. Williams, “Deliberately false statements to the police about matters that are within a suspect’s knowledge and materially relate to his or her guilt or innocence have long been considered cogent evidence of consciousness of guilt, for they suggest there is no honest explanation for incriminating circumstances.”143 In fact, when a suspect lies about a material matter, the jury at his trial may be instructed that such an act may properly be deemed a demonstration of guilt.144
LIES ABOUT PERIPHERAL ISSUES
Although less indicative of guilt than a lie about a material issue, lies about peripheral issues, such as the following, may also be viewed as incriminating:
• Suspect lied about his name, address, or DOB.145
• Suspect lied about his travel plans, destination, or point of origin.146
• Suspect lied that he wasn’t carrying ID.147
• Suspect lied that he didn’t have a key to his trunk.148
• Suspect lied that he didn’t own a car that was registered to him.149
• Suspect lied that he and the murder victim were not married.150
• Suspect lied when he said he didn’t know his accomplice.151
SUSPECT GIVES INCONSISTENT STATEMENT
A suspect who is making up a story while being questioned will frequently give conflicting information, often because he forgot what he said earlier or because he learned that his old story did not fit with the known facts. This is an especially significant circumstance if the conflict pertained to a material issue. For example, in People v. Memro the California Supreme Court pointed out that “patently inconsistent statements to such a vital matter as the whereabouts of [the murder victim] near the time he vanished had no discernible innocent meaning and strongly indicated consciousness of guilt.”152
SUSPECTS GIVE CONFLICTING STORIES
When two or more suspects are being questioned separately, they will often give conflicting stories because they do not know what the other had said. For example, in a stolen property case, People v. Garcia, one suspect said the stolen TV he was carrying belonged to some dude, but his companion said it belonged to the suspect. The court said it sounded fishy.153
Inconsistencies often frequently occur when officers stop a car and briefly question the occupants separately about where they came from, where they were going and why. Although these inconsistencies will not necessarily establish grounds to arrest or prolong the detention, they may naturally generate some suspicion. For example, in U.S. v. Guerrero 154 one of two suspected drug couriers said they had come to Kansas City “to work construction,” while the other said they were just visiting for the day. In ruling that the officers had grounds to detain the pair further, the court said that their “differing renditions of their travel plans” was “most important to the overall evaluation.”
INDEPENDENT WITNESS GAVE DIFFERENT STORY
Officers might reasonably believe that a suspect was lying if his statement was in material conflict with that of an independent witness who appeared to be believable. Some examples:
• The suspect denied reports of several witnesses who had told officers they had seen him arguing with a woman who was later raped and killed.155
• A murder suspect told officers that he left home at 8 A.M. (after his employer had been killed), but his mother said he left well before then.156
• A man suspected of having murdered a woman told officers that the woman had only been missing a week or so, but the woman’s mother said her daughter had been missing 3-4 weeks.157 UNBELIEVABLE STORIES: Although not a provable lie, the suspect’s story may generate suspicion because it didn’t make sense, or because it didn’t fit with the known facts.158
• A suspected drug dealer who was stopped for a traffic violation said he was driving from New Jersey to San Jose to fix a computer server for a company. “Yet if this were true,” said the court, “it was surely curious that the San Jose company would be willing to wait for Mr. Ludwig to drive cross-country.”159 Plus there are lots of people in San Jose (of all places) who can fix a server.
• A man who was found inside the locked apartment of a robbery suspect claimed he was not the suspect, but he couldn’t explain his presence there.160
• A suspected car thief said the car belonged to a friend, but he didn’t know his friend’s last name.161
• When questioned by DEA agents at San Diego International Airport, a woman who was carrying \$42,500 in cash inside a bag told them she had obtained the bag from a man named “Samuel,” a man she had just met at the airport and whose last name she didn’t know.162
• A burglary suspect told officers she was waiting for a friend, but she didn’t know her friend’s name; plus she said her friend would be arriving on a BART train from San Jose, but there are no BART stations in San Jose (at least until 2017).163
• A suspected rapist claimed he had been jogging, but he wasn’t perspiring or breathing hard, nor did he have a rapid pulse.164
AMBIGUOUS AnswerS
Even though a suspect technically answered the officer’s questions, his answers may be suspicious because they were ambiguous or bewildering.165
• Suspect “gave vague and evasive answers regarding his identity.”166
• Suspect gave an “unsatisfactory explanation” for being where he was detained.
• Suspects could not explain what they were doing in a residential area at 1:30 A.M.167
• Suspect gave “vague or conflicting answers to simple questions about his itinerary.”168
• Suspect gave “vague” description of her travel plans and she “could not remember the flight details”
WITHHOLDING INFORMATION
A suspect’s act of withholding material information from officers is a suspicious circumstance; e.g., murder suspect withheld information about his relationship with the victim.169
KNOWING TOO MUCH
A favorite of mystery writers for generations, a suspect’s act of providing officers with information that could only have been known by the perpetrator is so devastating that scores of fictional murderers, upon realizing their error, have felt compelled to immediately confess. Although he did not immediately do so, the defendant in People v. Spears was caught in exactly such a trap.170 Spears, an employee of a Chili’s restaurant in Cupertino, shot and killed the manager in the manager’s office shortly before the restaurant was to open for the day. When other employees arrived for work and Spears “discovered” the manager’s body, he exclaimed, “He’s been shot!” The manager had, in fact, been shot— three times to the head—but the damage to his skull was so extensive that only the killer would have known he had been shot, not bludgeoned. Spears was convicted.
Possession of Evidence
Another classic indication of guilt is that the suspect possessed the fruits or instrumentalities of the crime under investigation. But this one is a little more complicated because there are actually two independent legal issues: (1) Was the evidence “incriminating”? (2) Did the suspect actually “possess” it?
Types of incriminating evidence
There are essentially two types of incriminating evidence that a suspect may possess: contraband and circumstantial evidence of guilt. “Contraband” is anything that is illegal to possess, e.g., stolen property, child pornography, certain drugs, and illegal weapons.171 Possession of contraband automatically results in probable cause.
The other type of incriminating evidence, circumstantial evidence of guilt, is any evidence in the suspect’s possession that tends to—but does not directly—establish probable cause. The following are examples of circumstantial evidence of guilt:
• A suspected burglar possessed burglar tools.172
• A suspected drug dealer possessed a “bundle of small plastic baggies,” 173 or a “big stack or wad of bills.”174
• A murder suspect possessed bailing wire; bailing wire had been used to bind the victims.175
• A murder suspect possessed “cut-off panty hose”; officers knew the murderers had worn masks and that cut-off panty hose are often used as masks.176
• A man who had solicited the murder of his estranged wife possessed a hand-drawn diagram of his wife’s home and lighting system.177
• A robbery suspect possessed a handcuff key; the victim had been handcuffed.178
• A suspected car thief possessed a car with missing or improperly attached license plates, indications of VIN plate tampering, switched plates, a broken side window, or evidence of ignition tampering.179
Types of “possession”
In addition to having probable cause to believe the evidence is incriminating, officers must be able to establish probable cause to believe the suspect “possessed” it. There are types of possession: actual and constructive. Actual possession occurs if the evidence “is in the defendant’s immediate possession or control.”180 Examples include evidence in the suspect’s pockets or evidence that officers saw him discard or try to hide.181
In contrast, constructive possession exists if, although officers did not see the suspect physically possess the item, there was sufficient circumstantial evidence that he had sole or joint control over it.182 In the words of the Court of Appeal:
Constructive possession means the object is not in the defendant’s physical possession, but the defendant knowingly exercises control or the right to control the object.183
The question, then, is what constitutes sufficient circumstantial evidence of sole or joint control? The following circumstances are frequently cited by the courts:
CONTRABAND IN SUSPECT’S RESIDENCE
It is usually reasonable to infer that a suspect had control over contraband or other evidence in common areas of his home and in rooms over which he had joint or exclusive control; e.g., the kitchen,184 in a light fixture,185 in a bedroom.186
CONTRABAND IN A VEHICLE
The driver and all passengers in a vehicle are usually considered to be in control of items to which they had immediate access or which were in plain view; e.g., on the floorboard,187 behind an armrest,188 on a tape deck,189 behind the back seat.190
COMPANION IN POSSESSION
When officers have probable cause to believe a person possesses contraband, they may also have probable cause to arrest his companion for possession if there were facts that reasonably indicated they were acting in concert.191
INDICIA
A suspect’s control over a certain place or thing may be established by the presence of documents or other indicia linking him to the location; e.g., rent receipts, utility bills, driver’s license.192
Other Relevant Circumstances
Apart from circumstances that are too obvious to require discussion (e.g., confessions, fingerprint match,193 DNA hit,194 showup or lineup ID195 ), the following circumstances are frequently cited in establishing probable cause and reasonable suspicion:
SUSPECT’S PHYSICAL CONDITION
The fact that the suspect was injured, dirty, out-of-breath, sweating, or had torn clothing is highly suspicious if officers reasonably believed that the perpetrator would have been in such a condition.196
SUSPECT’S RAP SHEET
While it is somewhat significant that the suspect had been arrested or convicted in the past, it is highly significant that the crime was similar to the one under investigation.197
GANG CLOTHING
Depending on the nature of the crime, it may be relevant that the suspect was wearing clothing that is associated with a street gang.198
ELECTRONIC COMMUNICATION RECORDS
More and more, electronic communications records are providing officers with important information that establishes or helps to establish probable cause. Examples include phone numbers dialed and the length of the calls, cell site contact information (e.g., near scene of the crime when the crime occurred), date and time that a certain computer accessed a certain internet site, the identity of the sender and receiver of an email and when the communication occurred, the IP address assigned to a particular computer.199 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/05%3A_Arrests_Based_on_Probable_Cause/5.2%3A_Probable_Cause_to_Arrest.txt |
“An arrest is distinguished by the involuntary, highly intrusive nature of the encounter.”1
There is hardly anything that is more likely to louse up a criminal’s day than hearing the words: “You’re under arrest.” After all, it means the miscreant is now subject to an immediate, complete, and sometimes permanent loss of freedom. As the United States Supreme Court observed, an arrest is “the quintessential seizure of the person.”2
For these reasons, arrests are subject to several requirements that, as the Court explained, are intended “to safeguard citizens from rash and unreasonable interferences with privacy and from unfounded charges of crime.”3 As we will discuss in this article, these requirements can be divided into three categories:
1. GROUNDS FOR ARREST: Grounds for an arrest means having probable cause.
2. MANNER OF ARREST: The requirements pertaining to the arrest procedure include giving notice, the use of deadly and non-deadly force, the issuance and execution of arrest warrants, restrictions on warrantless misdemeanor arrests, searches incident to arrest, and entries of homes to arrest an occupant.
3. POST-ARREST PROCEDURE: In this category are such things as booking, phone calls, attorney visits, disposition of arrestees, probable cause hearings, arraignment, and even “perp walks.”
Before we begin, it should be noted that there are technically three types of arrests. The one we will be covering in this article is the conventional arrest, which is defined as a seizure of a person for the purpose of making him available to answer pending or anticipated criminal charges.4 A conventional arrest ordinarily occurs when the suspect was told he was under arrest, although the arrest does not technically occur until the suspect submits to the officer’s authority or is physically restrained.5
The other two are de facto and traffic arrests. De facto arrests occur inadvertently when a detention becomes excessive in its scope or intrusiveness.6 Like all arrests, de facto arrests are unlawful unless there was probable cause. A traffic arrest occurs when an officer stops a vehicle after seeing the driver commit an infraction. This is deemed an arrest because the officer has probable cause, and the purpose of the stop is to enforce the law, not conduct an investigation.7 Still, these stops are subject to the rules pertaining to investigative detentions.8
Probable Cause
Perhaps the most basic principle of criminal law is that an arrest requires probable cause. In fact, this requirement and the restrictions on force and searches are the only rules pertaining to arrest procedure that are based on the Constitution, which means they are enforced by the exclusionary rule. All the others are based on state statutes.9
Although we covered the subject of probable cause at length in a series of articles last year, there are some things that should be noted here.
DEFINED: Probable cause to arrest exists if there was a “fair probability” or “substantial chance” that the suspect committed a crime.10
WHAT PROBABILITY IS REQUIRED: Probable cause requires neither a preponderance of the evidence, nor “any showing that such belief be correct or more likely true than false.”11 Consequently, it requires something less than a 51% chance.12
ARRESTS “FOR INVESTIGATION”: Unlike officers on television and in movies, real officers cannot arrest suspects “for investigation” or “on suspicion” in hopes of obtaining incriminating evidence by interrogating them, putting them in a lineup, or conducting a search incident to arrest.13 This is because probable cause requires reason to believe the person actually committed a crime, not that he might have. As the Supreme Court said, “It is not the function of the police to arrest, as it were, at large and to use an interrogating process at police headquarters in order to determine whom they should charge.”14
MISTAKES OF LAW: There are two types of mistakes of law that can occur when officers arrest someone. First, there are mistakes as to the crime he committed; e.g., officers arrested the suspect for burglary, but the crime he actually committed was defrauding an innkeeper. These types of mistakes are immaterial so long as there was probable cause to arrest for some crime.15
The other type of mistake occurs when officers were wrong in their belief that there was probable cause to arrest. These types of mistakes render the arrest unlawful.16
PREMATURE WARRANTLESS ARRESTS
Although officers may consider their training and experience in determining whether probable cause to arrest exists, they must not jump to conclusions or ignore information that undermines probable cause. This is especially true if there was time to conduct further investigation before making the arrest. As the Seventh Circuit pointed out, “A police officer may not close her or his eyes to facts that would help clarify the circumstances of an arrest. Reasonable avenues of investigation must be pursued.”17
For example, in Gillan v. City of San Marino 18 a young woman told officers that, several months earlier while attending high school, she had been sexually molested by Gillan, her basketball coach. So they arrested him—even though the woman was unable to provide many details about the crime, even though some of the details she provided were inconsistent, even though she had a motive to lie (she had “strong antipathy” toward Gillian because of his coaching decisions), and even though they surreptitiously heard Gillan flatly deny the charge when confronted by the woman. After the DA refused to file charges, Gillan sued the officers for false arrest, and the jury awarded him over \$4 million.
On appeal, the court upheld the verdict, noting that the information known to the officers was “not sufficiently consistent, specific, or reliable” to constitute probable cause. Among other things, the court noted that “[s]ome of the allegations were generalized and not specific as to time, date, or other details, including claims of touching in the gym. Other accusations concerning more specific events either lacked sufficient detail or were inconsistent in the details provided.”
In another case, Cortez v. McCauley,19 a woman brought her two-year old daughter to an emergency room in New Mexico because her daughter had said that Cortez, an acquaintance, “hurt her pee pee.” A nurse at the hospital notified police who immediately arrested Cortez at his home. After prosecutors refused to file charges against him, Cortez sued the officers for false arrest.
In ruling that the officers were not entitled to qualified immunity, the Tenth Circuit pointed out that they “did not wait to receive the results of the medical examination of the child (the results were negative), did not interview the child or her mother, and did not seek to obtain a warrant.” Said the court, “We believe that the duty to investigate prior to a warrantless arrest is obviously applicable when a double-hearsay statement, allegedly derived from a two-year old, is the only information law enforcement possesses.”
Warrantless Arrests
When officers have probable cause to arrest, the courts prefer that they seek an arrest warrant.20 But they also understand that a rule prohibiting warrantless arrests would “constitute an intolerable handicap for legitimate law enforcement.”21 Consequently, warrantless arrests are permitted regardless of whether officers had time to obtain a warrant.22 As we will discuss, however, there are certain statutory restrictions if the crime was a misdemeanor.
Arrests for felonies and “wobblers”
If the suspect was arrested for a felony, the only requirement under the Fourth Amendment and California law is that they have probable cause.23 That’s also true if the crime was a “wobbler,” meaning a crime that could have been prosecuted as a felony or misdemeanor.24 Accordingly, if the crime was a felony or wobbler, officers may make the arrest at any time of the day or night,25 and it is immaterial that the crime did not occur in their presence.26
Arrests for misdemeanors
Because most misdemeanors are much less serious than felonies, there are three requirements (in addition to probable cause) that must be satisfied if the arrest was made without a warrant.
TIME OF ARREST
The arrest must have been made between the hours of 6 A.M. and 10 P.M. There are, however, four exceptions to this rule. Specifically, officers may make a warrantless misdemeanor arrest at any time in any of the following situations:
1. IN THE PRESENCE: The crime was committed in the officers’ presence. (See the “in the presence rule,” below.)
2. DOMESTIC VIOLENCE: The crime was a domestic assault or battery.
3. CITIZEN’S ARREST: The arrest was made by a citizen.
4. PUBLIC PLACE: The suspect was arrested in a public place.27
What is a “public” place? In the context of the Fourth Amendment, it is broadly defined as any place in which the suspect cannot reasonably expect privacy.28 Thus, a suspect is in a “public” place if he was on the street or in a building open to the public. Furthermore, the walkways and pathways in front of a person’s home usually qualify as “public places” because the public is impliedly invited to use them.29 In fact, the Supreme Court has ruled that a suspect who is standing at the threshold of his front door is in a “public place.”30
THE “IN THE PRESENCE” RULE
As a general rule, officers may not make warrantless misdemeanor arrests unless they have probable cause to believe the crime was committed in their “presence.”31 In discussing this requirement, the Court of Appeal explained, “This simply means that such an arrest may be made when circumstances exist that would cause a reasonable person to believe that a crime has been committed in his presence.”32 If the crime was not committed in the officers’ presence, and if they believe the suspect should be charged, they will ordinarily submit the case to prosecutors for review. They may not issue a citation in lieu of arrest.33
Although the “in the presence” requirement is an “ancient common-law rule,”34 it is not mandated by the Fourth Amendment.35 Instead, it is based upon a California statute,36 which means that evidence cannot be suppressed for a violation of this rule.37 What is “presence?” A crime is committed in the “presence” of officers if they saw it happening, even if they needed a telescope.38 A crime is also committed in the officers’ presence if they heard or smelled something that reasonably indicated the crime was occurring; e.g., officers overheard a telephone conversation in which the suspect solicited an act of prostitution, officers smelled an odor of marijuana.39 The question arises: Is a crime committed in the officers’ presence if they watched a video of the suspect committing it at an earlier time? It appears the answer is no.40 What if officers watched it live on a television or computer monitor? While there is no direct authority, it would appear that the crime would be occurring in their presence because there does not seem to be a significant difference between watching a crime-in-progress on a computer screen and watching it through a telescope.
While the courts frequently say that the “in the presence” requirement must be “liberally construed,”41 it will not be satisfied unless officers can testify, “based on [their] senses, to acts which constitute every material element of the misdemeanor.”42 In making this determination, however, officers may rely on circumstantial evidence and reasonable inferences based on their training and experience. For example, in People v. Steinberg 43 an LAPD officer received information that the defendant was a bookie and that he was working out of his rooming house. The officer went there and, from an open window, saw the defendant sitting near several items that indicated to the officer, an expert in illegal gambling, that the defendant was currently engaged in bookmaking. As the officer testified, the room “contained all the equipment and accoutrement commonly found in the rendezvous of the bookmaker.” In ruling that the crime of bookmaking had been committed in the officer’s presence, the court noted, “In the room where appellant had been seen engaged in his operations, the telephone was on his desk on which lay the National Daily Reporter and nearby were racing forms, pencils and ball point pens. . . . One sheet of paper was an ‘owe sheet’ on which was a record of the moneys owed by the bettors to the bookmaker, or the sum due from the latter to the bettors.”
Similarly, in a shoplifting case, People v. Lee,44 an officer in an apparel store saw Lee walk into the fitting room carrying five items of clothing. But when she left the room, she was carrying only three, which she returned to the clothing racks. The officer then checked the fitting room and found only one item, which meant that one was unaccounted for. So when Lee left the store, the officer arrested her and found the missing item in her purse. On appeal, Lee claimed the arrest was unlawful because the officer had not actually seen her conceal the merchandise in her purse. It didn’t matter, said the court, because the term “in the presence” has “historically been liberally construed” and thus “[n]either physical proximity nor sight is essential.”
EXCEPTIONS TO THE “IN THE PRESENCE” RULE
Arrests for the following misdemeanors are exempt from the “in the presence” requirement,45 presumably because of the overriding need for quick action:
ASSAULT AT SCHOOL: Assault or battery on school property when school activities were occurring.46
CARRYING LOADED GUN: Carrying a loaded firearm in a public place.
GUN IN AIRPORT: Carrying a concealed firearm in an airport.
DOMESTIC VIOLENCE PROTECTIVE ORDER: Violating a domestic violence protective order or restraining order if there was probable cause to believe the arrestee had notice of the order.
DOMESTIC VIOLENCE: Assault on a spouse, cohabitant, or the other parent of the couple’s child.
ASSAULT ON ELDER: Assault or battery on any person aged 65 or older who is related to the suspect by blood or legal guardianship.
ASSAULT ON FIREFIGHTER, PARAMEDIC: Assault on a firefighter, EMT, or paramedic engaged in the performance of his duties.
DUI PLUS: Even though officers did not see the suspect driving a vehicle, they may arrest him for DUI if, (1) based on circumstantial evidence, they had probable cause to believe he had been driving while under the influence; and (2) they had probable cause to believe that one or more of the following circumstances existed:
• He had been involved in an auto accident.
• He was in or about a vehicle obstructing a roadway.
• He would not be apprehended unless he was immediately arrested.
• He might harm himself or damage property if not immediately arrested.
• He might destroy or conceal evidence unless immediately arrested.
• His blood-alcohol level could not be accurately determined if he was not immediately arrested.
In addition, officers who have probable cause to arrest a juvenile for the commission of any misdemeanor may do so regardless of whether the crime was committed in their presence.46
“STALE” MISDEMEANORS
Even though a misdemeanor was committed in the officers’ presence, there is a long-standing rule that they may not arrest the suspect if they delayed doing so for an unreasonably long period of time.47 This essentially means that officers must make the arrest before doing other things that did not appear to be urgent. As the court explained in Jackson v. Superior Court, “[T]he officer must act promptly in making the arrest, and as soon as possible under the circumstances, and before he transacts other business.”48
Note that because this rule is not based on the Fourth Amendment, a violation cannot result in the suppression of evidence. Still, a lengthy delay should be considered by officers in determining whether the suspect should be cited and released.
Warrant Arrests
As noted earlier, an arrest is lawful under the Fourth Amendment if officers have probable cause. What, then, is the purpose of seeking an arrest warrant? After all, the United States Supreme Court has pointed out that it “has never invalidated an arrest supported by probable cause solely because the officers failed to secure a warrant.”49
There are essentially four situations in which officers will apply for a warrant. First, if the suspect has fled or if officers will otherwise be unable to make an immediate arrest, they may seek a warrant in order to download the arrest authorization into an arrest-warrant database such as NCIC. Second, as we will discuss later, an arrest warrant will ordinarily be required if officers will need to forcibly enter the suspect’s residence to make the arrest. Third, as discussed earlier, a warrant may be required if the crime was a misdemeanor that was not committed in an officer’s presence. Finally, if officers are uncertain about the existence of probable cause, they may seek an arrest warrant so as to obtain a judge’s determination on the issue which, in most cases, will also trigger the good faith rule.50 Apart from these practical reasons for seeking an arrest warrant, there is a philosophical one: the courts prefers that officers seek warrants when possible because, as the United States Supreme Court explained, they prefer to have “a neutral judicial officer assess whether the police have probable cause.” 51
The basics
Before we discuss the various types of arrest warrants that the courts can issue, it is necessary to cover the basic rules and principles that govern the issuance and execution of arrest warrants.
WARRANTS ARE COURT ORDERS
An arrest warrant is a court order directing officers to arrest a certain person if and when they locate him.52 Like a search warrant, an arrest warrant “is not an invitation that officers can choose to accept, or reject, or ignore, as they wish, or think, they should.”53
WHEN A WARRANT TERMINATES
An arrest warrant remains valid until it is executed or recalled.54
CHECKING THE WARRANT’S VALIDITY
Officers are not required to confirm the propriety of a warrant that appears valid on its face.55 They may not, however, ignore information that reasonably indicates the warrant was invalid because, for example, it had been executed or recalled, or because probable cause no longer existed.56 [Case-in-point: The Carter County Sheriff ’s Department in Tennessee recently discovered an outstanding warrant for the arrest of J.A. Rowland for passing a \$30 bad check. The warrant had been issued in 1928, and was payable to a storage company that ceased to exist decades ago. Said the sheriff with tongue in cheek, “This is still a legal document. We’ll have to start a manhunt for this guy.”]
INVESTIGATING THE ARRESTEE’S IDENTITY
An arrest will ordinarily be upheld if the name of the arrestee and the name of the person listed on the warrant were the same.70 But officers may not ignore objective facts that reasonably indicate the person they were arresting was not, in fact, the person named in the warrant; e.g., discrepancy in physical description, date of birth.58
CONFIRMING THE WARRANT
To make sure that an arrest warrant listed in a database had not been executed or recalled, officers will ordinarily confirm that it is still outstanding.59
WARRANTS SENT BY EMAIL OR FAX
An arrest warrant or a warrant abstract sent from one agency to another via email or fax has the same legal force as the original warrant.60
TIME OF ARREST
Officers may serve felony arrest warrants at any hour of the day or night.61 However, misdemeanor warrants may not be served between the hours of 10 P.M. and 6 A.M. unless, (1) officers made the arrest in a public place, (2) the judge who issued the warrant authorized night service, or (3) the arrestee was already in custody for another offense.62
The question has arisen on occasion: If officers are inside a person’s home after 10 P.M. because, for instance, they are taking a crime report, can they arrest an occupant if they should learn that he is wanted on a misdemeanor warrant that is not endorsed for night service? Although there is no case law directly on point, the California Court of Appeal has pointed out that the purpose of the time limit on misdemeanor arrests “is the protection of an individual’s right to the security and privacy of his home, particularly during night hours and the avoidance of the danger of violent confrontations inherent in unannounced intrusion at night.”63 It is at least arguable that none of these concerns would be implicated if officers had been invited in. But, again, the issue has not been decided.
Conventional arrest warrants
A conventional arrest warrant—also known as a complaint warrant—is issued by a judge after prosecutors charged the suspect with a crime.64 Such a warrant will not, however, be issued automatically simply because a complaint had been filed with the court. Instead, a judge’s decision to issue one—like the decision to issue a search warrant—must be based on facts that constitute probable cause.65 For example, a judge may issue a conventional arrest warrant based on information contained in an officer’s sworn declaration, which may include police reports and written statements by the victim or witnesses, so long as there is reason to believe the information is accurate. As the California Supreme Court explained:
The information in the complaint or affidavit in support thereof must either (1) state facts within the personal knowledge of the affiant or complainant directly supportive of allegations in the complaint that the defendant committed the offense; or (2) when such stated facts are not within the personal knowledge of the affiant or complainant, further state facts relating to the identity and credibility of the source of the directly incriminating information.66
MISDEMEANOR WARRANTS
Warrants may be issued for misdemeanors, as well as felonies.67
REQUIRED INFORMATION
The warrant must include the name of the person to be arrested, the date and time it was issued, the city or county in which it was issued, the name of the court, and the judge’s signature.68 The warrant must also contain the amount of bail or a “no bail” endorsement.69
JOHN DOE WARRANTS
If officers don’t know the suspect’s name, they may obtain a John Doe warrant, but it must contain enough information about the suspect to sufficiently reduce the chances of arresting the wrong person.70 As the court explained in People v. Montoya, “[A] John Doe warrant must describe the person to be seized with reasonable particularity. The warrant should contain sufficient information to permit his identification with reasonable certainty.”71 Similarly, the court in Powe v. City of Chicago noted that, “[w]hile an arrest warrant may constitutionally use such arbitrary name designations, it may do so only if, in addition to the name, it also gives some other description of the intended arrestee that is sufficient to identify him.”72
For example, in U.S. v. Doe, where the person named on the arrest warrant was identified only as “John Doe a/k/a Ed,” the court ruled the warrant was invalid because “the description did not reduce the number of potential subjects to a tolerable level.”73 Thus, a John Doe warrant should include, in addition to a physical description, any information that will help distinguish the arrestee, such as his home or work address, a description of the vehicles he drives, the places where he hangs out, and the names of his associates.74 Whenever possible, a photo of the suspect should also be included.
IF THE WARRANT CONTAINS AN ADDRESS
There are two reasons for including the suspect’s address on an arrest warrant. First, as just noted, if it’s a John Doe warrant an address may be necessary to help identity him.75 Second, the address may assist officers in locating the suspect. Otherwise, an address on a warrant serves no useful purpose. As the court observed in Cuerva v. Fulmer, “In an arrest warrant, unlike a search warrant, the listed address is irrelevant to its validity and to that of the arrest itself.”76 The question has arisen: Does the inclusion of an address on a warrant constitute authorization to enter and search the premises for the arrestee? The answer is no.77 As we will discuss later, officers cannot enter a residence to execute an arrest warrant unless they have probable cause to believe that the suspect lives there, and that he is now inside. Thus, the legality of the entry depends on whether the officers have this information, not whether the residence is listed on the warrant.
Ramey warrants
In contrast to conventional arrest warrants, Ramey warrants are issued before a complaint has been filed against the suspect. The question arises: Why would officers seek a Ramey warrant instead of a conventional warrant? The main reason is that they cannot obtain a conventional warrant because, although they have probable cause, they do not have enough incriminating evidence to meet the legal standard for charging. So they seek a Ramey warrant—also known as a “Warrant of Probable Cause for Arrest”78—in hopes that by questioning the suspect in a custodial setting, by placing him in a physical lineup, or by utilizing some other investigative technique, they can convert their probable cause into proof beyond a reasonable doubt.
The procedure for obtaining a Ramey warrant— felony or misdemeanor 79—is essentially the same as the procedure for obtaining a search warrant. Specifically, officers must do the following:
1. Prepare declaration: Officers must prepare a “Declaration of Probable Cause” setting forth the facts upon which probable cause is based.
2. Prepare Ramey warrant: Officers will also complete the Ramey warrant which must contain the following: the arrestee’s name, the name of the court, name of the city or county in which the warrant was issued, a direction to peace officers to bring the arrestee before a judge, the signature and title of issuing judge, the time the warrant was issued, and the amount of bail (if any).80 See page 11 for a sample Ramey warrant.
3. Submit to judge: Officers submit the declaration and warrant to a judge. This can be done in person, by fax, or by email.81
Other arrest warrants
The following are the other kinds of warrants that constitute authorization to arrest:
STEAGALD WARRANT
This is a combination search and arrest warrant which is required when officers forcibly enter the home of a third person to arrest the suspect; e.g., the home of the suspect’s friend or relative. See “Entering a Home to Arrest an Occupant,” below. Also see Page 11 for a sample Steagald warrant.
INDICTMENT WARRANT
An indictment warrant is issued by a judge on grounds that the suspect had been indicted by a grand jury.82
PAROLE VIOLATION WARRANT
Issued by the parole authority when there is probable cause to believe that a parolee violated the terms of release.83
PROBATION VIOLATION WARRANT
Issued by a judge based on probable cause to believe that a probationer violated the terms of probation.84
BENCH WARRANT
Issued by a judge when a defendant fails to appear in court.85
WITNESS FTA WARRANT
Issued by a judge for the arrest of a witness who has failed to appear in court after being ordered to do so.86
Arrest Formalities
Under California law, there are three technical requirements with which officers must comply when making an arrest. They are as follows:
NOTIFICATION
Officers must notify the person that he is under arrest.87 While this is usually accomplished directly (“You’re under arrest”), any other words or conduct will suffice if it would have indicated to a reasonable person that he was under arrest; e.g., suspect was apprehended following a pursuit,88 officer took the suspect by the arm and told him he had a warrant for his arrest.89 Furthermore, notification is unnecessary if the suspect was apprehended while committing the crime.90
SPECIFY AUTHORITY
Officers must notify the suspect of their authority to make the arrest.91 Because this simply means it must have been apparent to the suspect that he was being arrested by a law enforcement officer, this requirement is satisfied if the officer was in uniform or he displayed a badge.92
SPECIFY CRIME
If the suspect wants to know what crime he is being arrested for, officers must tell him.93 (As noted earlier, it is immaterial that officers specified the “wrong” crime.)
Searches Incident to Arrest
When officers arrest a suspect, they may ordinarily conduct a limited search to locate any weapons or destructible evidence in the arrestee’s possession and in the immediate vicinity. This type of search— known as a search incident to arrest—may be made as a matter of routine, meaning that officers will not be required to prove there was reason to believe they would find weapons or evidence in the places they searched. As the United States Supreme Court explained:
The authority to search the person incident to a lawful custodial arrest, while based upon the need to disarm and to discover evidence, does not depend on what a court may later decide was the probability in a particular arrest situation that weapons or evidence would in fact be found upon the person of the suspect.94
Requirements
Officers may conduct a search incident to arrest if the following circumstances existed:
1. Probable cause: There must have been probable cause to arrest the suspect.
2. Custodial arrest: The arrest must have been “custodial” in nature, meaning that officers had decided to transport the arrestee to jail, a police station, a detox facility, or a hospital.
3. Contemporaneous search: The search must have occurred promptly after the arrest was made.95
Scope of search
The following places and things may be searched incident to an arrest:
ARRESTEE’S CLOTHING
Officers may conduct a “full search” of the arrestee.96 Although the term “full search” is vague, the courts have ruled that it permits a more intensive search than a pat down; and that it entails a “relatively extensive exploration” of the arrestee, including his pockets.97
A more invasive search can never be made as a routine incident to an arrest.98 For example, officers may not conduct a partial strip search or reach under the arrestee’s clothing. Such a search would almost certainly be permitted, however, if, (1) officers had probable cause to believe the suspect was concealing a weapon or evidence that could be destroyed or corrupted if not seized before the suspect was transported, and (2) they had probable cause to believe the weapon or evidence was located in the place or thing that was searched.99 Moreover, such a search would have to be conducted in a place and under circumstances that would adequately protect the arrestee’s privacy.100
CONTAINERS
Officers may search containers in the arrestee’s immediate control when he was arrested (e.g., wallet, purse, backpack, hide-a-key box, cigarette box, pillbox, envelope 101), even if he was not carrying the item when he was arrested, and even if officers knew he was not the owner.102 CELL PHONES: This is currently a hot topic: Can officers search the arrestee’s cell phone for evidence pertaining to the crime for which he was arrested?103 At least two federal circuit courts have upheld such searches in published opinions,104 while some district courts have ruled otherwise.105 Stay tuned.
PAGERS
There is limited authority for retrieving numerical data from pagers in the arrestee’s possession if such information would constitute evidence of the crime under investigation.106
ITEMS TO GO WITH ARRESTEE
If the arrestee wants to take an item with him, and if officers permit it, they may search the item.107
VEHICLES
Officers may search the passenger compartment of a vehicle in which the arrestee was an occupant.108
RESIDENCES
If the suspect was arrested inside a residence, officers may search places and things in the area within his grabbing or lunging distance at the time he was arrested.109 Officers may also search the area “immediately adjoining” the place of arrest—even if it was not within his immediate control—but these searches must be limited to spaces in which a potential attacker might be hiding.110 [For a more detailed discussion of this subject, see the 2005 article entitled “Searches Incident to Arrest” on Online.]
Use of Force
It is, of course, sometimes necessary to use force to make an arrest.111 In fact, the Eleventh Circuit pointed out that “the use of force is an expected, necessary part of a law enforcement officer’s task of subduing and securing individuals suspected of committing crimes.”112 The question arises: How does the law distinguish between permissible and excessive force? The short answer is that force is permissible if it was reasonably necessary.113 “When we analyze excessive force claims,” said the Ninth Circuit, “our initial inquiry is whether the officers’ actions were objectively reasonable in light of the facts and circumstances confronting them.”114
Like the other police actions that are governed by the standard of “reasonableness,” the propriety of the use of force is intensely fact-specific. Thus, in applying this standard in a pursuit case, the U.S. Supreme Court began by noting, “[I]n the end we must still slosh our way through the factbound morass of ‘reasonableness.’"115 The problem for officers is that their decisions on the use of force must be made quickly and under extreme pressure, which means there is seldom time for “sloshing.”116 Taking note of this problem, the Court ruled that a hypertechnical analysis of the circumstances is inappropriate:
The “reasonableness” of a particular use of force must be judged from the perspective of a reasonable officer on the scene, rather than with the 20/20 vision of hindsight. The calculus of reasonableness must embody allowance for the fact that police officers are often forced to make split-second judgments—in circumstances that are tense, uncertain, and rapidly evolving—about the amount of force that is necessary in a particular situation.117
For this reason, an officer’s use of force will not be deemed excessive merely because there might have been a less intrusive means of subduing the suspect.118 As noted in Forrester v. City of San Diego, “Police officers are not required to use the least intrusive degree of force possible. Rather, the inquiry is whether the force that was used to effect a particular seizure was reasonable.”119
Because the reasonableness of any use of force will ultimately depend on the severity or “quantum” of the force utilized by officers, the courts usually begin their analysis by determining whether the force was deadly, non-deadly, or insignificant.120
Non-deadly force
Force is deemed “non-deadly” if it does not create a substantial risk of causing death or serious bodily injury.121 To determine whether non-deadly force was reasonably necessary, the courts apply a balancing test in which they examine both the need for the force and its severity. And if need outweighs or is proportionate to the severity, the force will be deemed reasonable.122 Otherwise, it’s excessive. As the United States Supreme Court explained in Graham v. Connor:
Determining whether the force used to effect a particular seizure is “reasonable” under the Fourth Amendment requires a careful balancing of the nature and quality of the intrusion on the individual’s Fourth Amendment interests against the countervailing governmental interests at stake.123
THE NEED FOR FORCE
The first issue in any use-offorce case is whether there was an objectively reasonable need for force. As the Ninth Circuit observed, “[I]t is the need for force which is at the heart of [the matter].”124 In most cases, the need will be based solely on the suspect’s physical resistance to arrest;125 e.g., the arrestee “spun away from [the arresting officer] and continued to struggle,”126 the arrestee “stiffened her arm and attempted to pull free.” 127
On the other hand, if the suspect was not resisting, there would be no need for any force, other than the de minimis variety. Thus, in Drummond v. City of Anaheim, the court ruled that an officer’s use of force was unreasonable because, “once Drummond was on the ground, he was not resisting the officers; there was therefore little or no need to use any further physical force.”128 Similarly, in Parker v. Gerrish the court observed, “In some circumstances, defiance and insolence might reasonably be seen as a factor which suggests a threat to the officer. But here [the suspect] was largely compliant and twice gave himself up for arrest to the officers.”129
Although force is seldom necessary if the arrestee was not presently resisting, there may be a need for it if the suspect had been actively resisting and, although he was not combative at the moment, he was not yet under the control of the arresting officers. This is especially true if there was probable cause to arrest him for a serious felony.130 For example, in ruling that officers did not use excessive force in pulling a bank robbery suspect from his getaway car, the court in Johnson v. County of Los Angeles noted that, even though the suspect was not “actively resisting arrest,” it is “very difficult to imagine that any police officer facing a moving, armed bank robbery suspect would have acted any differently—at least not without taking the very real risk of getting himself or others killed. The need to quickly restrain Johnson by removing him from the car and handcuffing him was paramount.”131
The need for force will increase substantially if the suspect’s resistance also constituted a serious and imminent threat to the safety officers or others.132 Thus, in Scott v. Harris, a vehicle pursuit case, the Supreme Court upheld the use of the PIT maneuver to end a high-speed chase because, said the court, “[I]t is clear from the videotape [of the pursuit] that [the suspect] posed an actual and imminent threat to the lives of any pedestrians who might have been present, to other civilian motorists, and to the officers involved in the chase.”133 Similarly, in Miller v. Clark County, the court noted that Miller attempted “to flee from police by driving a car with a wanton or willful disregard for the lives of others.”134
PROPORTIONATE RESPONSE BY OFFICERS
Having established a need for some force, the courts will look to see whether the amount of force utilized was commensurate with that need.135 As the court explained in Lee v. Ferraro, “[T]he force used by a police officer in carrying out an arrest must be reasonably proportionate to the need for the force, which is measured by the severity of the crime, the danger to the officer, and the risk of flight.”136 For example, utilizing a control hold,137 pepper stray,138 “hard pulling,”139 or a trained police dog 140 will often be deemed reasonably necessary if officers were facing resistance that was moderate to severe.
TASERS
Although the shock caused by tasers is currently classified as non-deadly force,141 the courts are aware that it is quite painful and that the consequences are not always predictable. In fact, some people have died after being tased. As a result, some courts have classified tasers as “intermediate” force, which requires a demonstrably greater need than non-deadly force.142 As the court in Beaver v. City of Federal Way observed:
While the advent of the Taser has undeniably provided law enforcement officers with a useful tool to subdue suspects with a lessened minimal risk of harm to the suspect or the officer, it is equally undeniable that being “tased” is a painful experience. The model used by [the officer] delivers a full five-second cycle of electrical pulses of a maximum of 50,000 volts at very low amperage that interrupts a target’s motor system and causes involuntary muscle contraction.143
Still, tasing is often deemed justified when there was significant resistance, especially if officers had been unable to control the arrestee by other means. Thus, the Eleventh Circuit noted, “[I]n a difficult, tense and uncertain situation the use of a taser gun to subdue a suspect who has repeatedly ignored police instructions and continues to act belligerently toward police is not excessive force.”144
For example, in Draper v. Reynolds 145 the court ruled that the use of a taser to subdue a suspect was proportionate because, among other things, the suspect “was hostile, belligerent, and uncooperative. No less than five times, [the officer] asked [the suspect] to retrieve documents from the truck cab, and each time [the suspect] refused to comply. . . . [The suspect] used profanity, moved around and paced in agitation, and repeatedly yelled at [the officer].” Said the court, “Although being struck by a taser gun is an unpleasant experience, the amount of force [the officer] used—a single use of the taser gun causing a one-time shocking—was reasonably proportionate to the need for force and did not inflict any serious injury.”
Similarly, in Sanders v. City of Fresno 146 the court ruled that the use of a taser was reasonable because, among other things, the suspect “was agitated, did not obey the request to let [his wife] go, believed that the officers were there to kill him and/or take [his wife] away from him, appeared to be under the influence of drugs . . . ”
MENTALLY UNSTABLE ARRESTEES
It should be noted that an officer’s use of force will not be deemed excessive merely because the arrestee was mentally unstable. Still, it is a circumstance that should, when possible, be considered in deciding how to respond. As the Ninth Circuit observed:
The problems posed by, and thus the tactics to be employed against, an unarmed, emotionally distraught individual who is creating a disturbance or resisting arrest are ordinarily different from those involved in law enforcement efforts to subdue an armed and dangerous criminal who has recently committed a serious offense. In the former instance, increasing the use of force may, in some circumstances at least, exacerbate the situation . . . 147
Deadly force
In the past, deadly force was defined as action that was “reasonably likely to kill.”148 Now, however, it appears that most courts define it more broadly as action that “creates a substantial risk of causing death or serious bodily injury.”149
Under the Fourth Amendment, the test for determining whether deadly force was justified is essentially the same as the test for non-deadly force. I both cases, the use of force is lawful if it was reasonable under the circumstances.150 The obvious difference is that deadly force cannot be justified unless there was an especially urgent need for it. As the United States Supreme Court observed, “[N]otwithstanding probable cause to seize a suspect, an officer may not always do so by killing him. The intrusiveness of a seizure by means of deadly force is unmatched.”151
The Court has acknowledged, however, that there is “no obvious way to quantify the risks on either side,” that there is no “magical on/off switch” for determining the point at which deadly force is justified,152 and that the test is “cast at a high level of generality.”153 Still, it has ruled that the use of deadly force can be justified under the Fourth Amendment only if the following circumstances existed:
1. RESISTING ARREST: The arrestee must have been fleeing or otherwise actively resisting arrest.
2. THREAT TO OFFICERS OR OTHERS: Officers must have had probable cause to believe that the arrestee posed a significant threat of death or serious physical injury to officers or others.154
3. WARNING: Officers must, “where feasible,” warn the arrestee that they are about to use deadly force.155
As the Court observed in Tennessee v. Garner, “Where the officer has probable cause to believe that the suspect poses a threat of serious physical harm, either to the officer or to others, it is not constitutionally unreasonable to prevent escape by using deadly force.”156
Although most threats that will justify deadly force pose an immediate threat to officers or others,157 in some cases an impending or imminent threat will suffice. Such a threat may exist if officers reasonably believed—based on the nature of the suspect’s crime, his state of mind, and any other relevant circumstances—that his escape would pose a severe threat of serious physical harm to the public. As the Supreme Court explained in Scott v. Harris, deadly force might be reasonably necessary “to prevent escape when the suspect is known to have committed a crime involving the infliction or threatened infliction of serious physical harm, so that his mere being at large poses an inherent danger to society.”158 (The Court in Garner ruled that a fleeing burglar did not present such a threat.159).
The use of deadly force will not, of course, be justified after the threat had been eliminated. For example, in Waterman v. Batton the Fourth Circuit ruled that, while officers were justified in firing at the driver of a car that was accelerating toward them, they were not justified in shooting him after he had passed by. Said the court, “[F]orce justified at the beginning of an encounter is not justified even seconds later if the justification for the initial force has been eliminated.” 160
It should be noted that the test for determining whether deadly force was reasonable under the Fourth Amendment is essentially the same as the test for determining whether officers may be prosecuted for using deadly force that results in the death of a suspect. Specifically, Penal Code § 196 has been interpreted to mean that officers cannot be criminally liable if the suspect was actively resisting and, (1) “the felony for which the arrest is sought is a forcible and atrocious one which threatens death or serious bodily harm,” or (2) “there are other circumstances which reasonably create a fear of death or serious bodily harm to the officer or to another.”161
Entering a home to arrest an occupant
In the past, officers could forcibly enter a residence to arrest an occupant whenever they had probable cause to arrest. Now, however, a forcible entry is permitted only if there were additional circumstances that justified the intrusion. As we will now explain, the circumstances that are required depend on whether officers enter the suspect’s home or the home of a third person, such as a friend or relative of the suspect.
Entering the suspect’s home
To enter the suspect’s home, officers must comply with the so-called Ramey-Payton rule,162 under which a forcible entry is permitted only if both of the following circumstances existed:
1. WARRANT ISSUED: A warrant for the suspect’s arrest must have been outstanding. Either a conventional or Ramey warrant will suffice.163
2. ARRESTEE’S HOME: Officers must have had “reason to believe” the suspect, (a) lived in the residence, and (b) was presently inside. Although most federal courts have ruled that the “reason to believe” standard is merely reasonable suspicion,164 the Ninth Circuit ruled it means probable cause.165 The California Supreme Court has not yet decided.166
Entering a third person’s home
If the suspect is inside the home of a third person, such as a friend or relative, the so-called Steagald rule applies, which means that officers may enter only if they have a search warrant supported by an affidavit that establishes probable cause to believe, (1) the suspect committed the crime under investigation, and (2) he is presently inside the residence and will be there when the warrant is executed.167 See page 11 for a sample Steagald warrant.
Other grounds for entering
There are essentially three situations in which officers without a warrant may enter a residence to arrest an occupant:
“HOT PURSUIT”
Officers may enter if they are in “hot pursuit” of the suspect. In this context of executing arrest warrants, the term “hot pursuit” means a situation in which all of the following circumstances existed:
1. PROBABLE CAUSE TO ARREST: Officers must have had probable cause to arrest the suspect for a felony or misdemeanor.
2. ATTEMPT TO ARREST OUTSIDE: Officers must have attempted to make the arrest outside the residence.
3. SUSPECT FLEES INSIDE: The suspect must have tried to escape or otherwise prevent an immediate arrest by going inside the residence.168
“FRESH PURSUIT”
Officers may also enter a residence without a warrant to arrest an occupant if they are in “fresh pursuit.” This essentially means they must have been actively attempting to locate the arrestee and, in doing so, were quickly responding to developing information as to his whereabouts. Although the courts have not established a checklist of requirements for fresh pursuits, the cases seem to indicate there are four:
1. SERIOUS FELONY: Officers must have had probable cause to arrest the suspect for a serious felony, usually a violent one.
2. DILIGENCE: Officers must have been diligent in attempting to apprehend the suspect.
3. SUSPECT INSIDE: Officers must have had probable cause to believe the suspect was inside the structure.
4. CIRCUMSTANTIAL EVIDENCE OF FLIGHT: Officers must have been aware of circumstances indicating the suspect was in active flight or that active f light was imminent.169
CONSENT
If officers obtained consent to enter from the suspect or other occupant, the legality of their entry will usually depend on whether they misled the consenting person as to their objective, so that an immediate arrest would have exceeded the scope of consent. For example, if officers said they merely wanted to enter (“Can we come in?”) or talk (“We’d like to talk to you.), a court might find that they exceeded the permissible scope of the consent if they immediately arrested him.170 But there should be no problem if officers intended to make the arrest only if, after speaking with the suspect, they believed that probable cause existed or continued to exist.171
[For a more detailed discussion of this subject, see the 2005 article “Entry to Arrest” on Online.]
Post-Arrest Procedure
Although the lawfulness of an arrest will depend on what the officers did at or near the time the suspect was taken into custody, there are certain procedural requirements that must be met after the arrest is made.
BOOKING
Booking is “merely a ministerial function”172 which involves the “recordation of an arrest in official police records, and the taking by the police of fingerprints and photographs of the person arrested.”173 While the California Penal Code does not require booking,174 it is considered standard police procedure because one of its primary purposes is to confirm the identity of the arrestee.175 For this reason, booking is permitted even if officers were aware that the arrestee would be posting bail immediately.176
PHONE CALLS
The arrestee has a right to make completed telephone calls to the following: an attorney, a bail bondsman, and a relative. Furthermore, he has a right to make these calls “immediately upon being booked,” and in any event no later than three hours after the arrest except when it is “physically impossible.”177
ATTORNEY VISITS
Officers must permit the arrestee to visit with an attorney if the arrestee or a relative requested it.178
PROBABLE CAUSE DETERMINATION
If the suspect was arrested without a warrant, and if he has not bailed out,179 a judge must determine whether there was probable cause for the arrest. While such a determination must be made “promptly,”180 there is a presumption of timeliness if the determination was made within 48 hours after arrest.181 Note that in calculating the time limit, no allowance is made for weekends and holidays—it’s a straight 48 hours.182
What must officers do to comply with this requirement? They will usually submit a Declaration of Probable Cause which contains a summary of the facts upon which probable cause was based.
Note that a suspect may not be released from custody based on a tardy probable cause determination,183 nor may the charges be dismissed.184 However, statements made by the arrestee after the 48 hours had expired might be suppressed if the court finds that probable cause to arrest did not exist.
ARRAIGNMENT
After an arrestee has been charged with a crime by prosecutors (and thus becomes a “defendant”), he must be arraigned. An arraignment is usually a defendant’s first court appearance during which, among other things, a defense attorney is appointed or makes an appearance; the defendant is served with a copy of the complaint and is advised of the charges against him; the defendant pleads to the charge or requests a continuance for that purpose; and the judge sets bail, denies bail, or releases the defendant on his own recognizance.
A defendant must be arraigned within 48 hours of his arrest 185 unless, (1) he was released from custody,186 or (2) he was being held on other charges or a parole hold.187 Unlike the time limit for probable cause determinations, the 48-hour countdown does not include Sundays and holidays.188 Furthermore, if time expires when court is in session, the defendant may be arraigned anytime that day.189 If court is not in session, he may be arraigned anytime the next day.190 If, however, the arrest occurred on Wednesday after the courts closed, the arraignment must take place on Friday, unless Wednesday or Friday were court holidays.191
Note that short delays are permitted if there was good cause; e.g., defendant was injured or sick.192 A short delay may also be justified if, (1) the crime was serious; (2) officers were at all times diligently engaged in actions they reasonably believed were necessary to obtain necessary evidence or apprehend additional perpetrators; and (3) officers reasonably believed that these actions could not be postponed without risking the loss of necessary evidence, the identification or apprehension of additional suspects, or otherwise compromising the integrity of their investigation.193
5.4: Illinois v. Gates
PETITIONER RESPONDENT
Illinois Lance Gates, et ux
LOCATION
Residence of Gates
DOCKET NO. DECIDED BY
81-430 Burger Court
LOWER COURT
Supreme Court of Illinois
CITATION
462 US 213 (1983)
ARGUED
Oct 13, 1982
REARGUED
Mar 1. 1983
DECIDED
June 8, 1983
ADVOCATES
Paul P. Biebel, Jr. Reargued the cause for the petitioner
James W . Reilley Reargued the cause for the respondents
Rex E. Lee Argued the case on re-argument for the United States as amicus curiae urging reversal
Paul B. Biebel Jr. on behalf of petitioner
Facts of the case
The Bloomingdale, Illinois Police Department received an anonymous tip that Lance and Susan Gates were selling drugs out of their home. After observing the Gates's drug smuggling operation in action, police obtained a warrant and upon searching the suspects' car and home uncovered large quantities of marijuana, other contraband, and weapons.
Question
Did the search of the Gates's home violate the Fourth and Fourteenth Amendments?
Conclusion
6–3 Decision for Illinois
Majority Opinion by William H. Rehnquist
FOR AGAINST
Blackmun
White
Powell
Burger
O’Conner
Rehnquist
Marshall
Brennan
Stevens
The Court found no constitutional violation and argued that the lower court misapplied the test for probable cause which the Court had announced in Spinelli v. United States (1969). Justice Rehnquist argued that an informant's veracity, reliability, and basis of knowledge are important in determining probable cause, but that those issues are intertwined and should not be rigidly applied. He argued that the"totality-of-the-circumstances" approach to probable cause was the correct one to glean from Spinelli, and that the law enforcement officials who obtained a warrant abided by it in this case. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/05%3A_Arrests_Based_on_Probable_Cause/5.3%3A_Arrests.txt |
Let’s go search my apartment. You can search the shit out of it. I’ll even help you.1
That was a major league bluff. And soon after suspected murderer Eugene Wheeler made his bold offer in an LAPD interview room, he must have realized he had blundered. That’s because the detectives gracefully accepted his offer, then diligently searched his apartment and found the murder weapon hidden behind a wall-mounted music speaker. So, thanks in part to his hubris, Wheeler was convicted of first degree murder.
Why did he take such a chance? Actually, there are several logical reasons.2 As the Court of Appeal pointed out, a suspect “may wish to appear cooperative in order to throw the police off the scent or at least to lull them into conducting a superficial search; he may believe the evidence is of such a nature or in such a location that it is likely to be overlooked; he may be persuaded that if the evidence is nevertheless discovered he will be successful in explaining its presence or denying any knowledge of it; he may intend to lay the groundwork for ingratiating himself with the prosecuting authorities or the courts; or he may simply be convinced that the game is up and further dissembling is futile.”3
But whatever a suspect’s motivation, the thing to remember for officers is that, when it comes to consent searches, there’s no harm in asking. In fact, the Supreme Court has described them as a “wholly legitimate aspect of effective police activity” which is often “the only means of obtaining important and reliable evidence.”4 Of course, such evidence is worthless unless it is admissible in court, and that is why we are devoting this edition of to the rules that govern consent searches.
As we will explain, there are four basic requirements:
1. Consent was given: The suspect must have expressly or impliedly consented.
2. Consent was voluntary: The consent must have been given voluntarily.
3. Scope of consent: Officers must have searched only those places and things that the suspect expressly or impliedly authorized them to search.
4. Intensity of search: The search must not have been unduly intrusive.
In addition to these requirements, we will discuss two issues that frequently arise: mid-search withdrawal of consent and consent obtained by means of trickery. Then in the accompanying article, “Third Party Consent,” we will explain the rules for obtaining consent to search a suspect’s property from someone other than the suspect, such as his spouse, roommate, or accomplice.
Did he consent?
The most basic requirement is that the suspect must have consented—either expressly or impliedly.
EXPRESS CONSENT
Express consent results when the suspect responds in the affirmative to an officer’s request for permission. There are, however, no “magic words” that the suspect must utter.5 Instead, express consent may be given by means of any words or gestures that reasonably indicate the suspect was consenting. Express consent will also result if, like Mr. Wheeler, the suspect suggested it.
IMPLIED CONSENT TO SEARCH
Consent will be implied if the suspect said or did something that officers reasonably interpreted as authorization to search.6 As the Court of Appeal explained, “Specific words of consent are not necessary; actions alone may be sufficient.”7 For example, consent to search a home or vehicle has been implied when the suspect responded to the officer’s request to search by handing him the keys;8 and when an officer told the suspect what he was looking for and when the suspect responded by telling them where it was located.9 However, a failure to object to a search does not constitute consent.10
Voluntary Consent
In addition to proving that the suspect expressly or impliedly consented, officers must prove that his consent had been given voluntarily.11 This simply means the consent must not have been the result of threats, promises, intimidation, demands, or any other method of pressuring the suspect to consent.12 “Where there is coercion,” said the Supreme Court, “there cannot be consent.”13
It has been argued (usually out of desperation) that any consent search that results in the discovery of incriminating evidence must have been involuntary because no lucid criminal would voluntarily do something that would likely land him in jail. But, as the Court of Appeal observed, these arguments have “never been dispositive of the issue of consent.”14 For example, the Sixth Circuit observed in U.S. v. Carter 15 that, while the defendant’s decision to consent “may have been rash and ill-considered, that does not make it invalid.”
Furthermore, if the suspect consented, it is immaterial that he was not joyful or enthusiastic about it.16 This is because “[n]o person, even the most innocent, will welcome with glee and enthusiasm the search of his home by law enforcement agents.”17 For example, consent to search has been found when, upon being asked for consent, the suspect responded “Yeah,” “I don’t care,” “No problem,” “Do what you gotta do,” and “Be my guest.”18
As we will now discuss, the circumstances that are relevant in determining whether consent was voluntary can be divided into four categories: (1) direct evidence of coercion, (2) circumstantial evidence of coercion, (3) circumstantial evidence of voluntariness, and (4) circumstantial evidence bearing on the suspect’s state of mind.
Direct evidence of coercion
Apart from physical violence, the most obvious forms of coercion are threats and demands—either of which will likely render consent involuntary.
THREATS
An officer’s threat to arrest or take punitive action against the suspect if he refused to consent will render the consent involuntary. For example, the courts have ruled that consent was involuntary when it resulted from an officer’s threat to arrest the suspect,19 terminate her welfare benefits,20 or remove her children from the home.21
DEMANDING CONSENT
Consent is also involuntary if officers said or suggested that, although they were asking for the suspect’s consent, he really had no choice. As the court observed in People v. Fields, “There is a world of difference between requesting one to open a trunk and asking one’s permission to look in a trunk.”22 Similarly, an officer’s entry into a home would not be consensual if he was admitted after announcing, “Police! Open the door!”23
Circumstantial evidence of coercion
Even if there were no explicit threats or demands, consent is involuntary if (1) a reasonable person in the suspect’s position would have viewed the officers’ words or conduct as coercive, and (2) there was no overriding circumstantial evidence of voluntariness (discussed in the next section).
INTIMIDATION
Consent is involuntary if it was obtained by the use of police tactics that were reasonably likely to elicit fear if it was denied.24 For example, in People v. Reyes 25 a narcotics officer induced Reyes to leave his home by claiming that Reyes’ parked car had been damaged in a traffic accident. As Reyes stepped outside, he was met by five officers, three of whom were “attired in full ninja-style raid gear, including black masks and bulletproof vests emblazoned with POLICE markings.” Although Reyes consented to a search his pockets (there were drugs), the court ruled the consent was involuntary because the officers had “lured him into a highly intimidating situation.” Said the court, “[W]e think the police went too far.” Some other examples:
• The suspect was “standing in a police spotlight, surrounded by four officers all armed with shotguns or carbines.”26
• “Six or seven officers strode into Poole’s apartment in order to ‘talk’ to him, without so much as a by-your-leave.”27
• “[A] half dozen uniformed police officers” asked for consent while “moving up the [suspect’s] stairs with pistols drawn.”28
BADGERING
If the suspect initially refused to consent, an officer’s badgering him into changing his mind is necessarily coercive. Officers may, however, ask the suspect to reconsider his decision so long as they are not overly persistent.29 When does mere persistence become badgering? Although the line may be difficult to draw, it may depend a lot on the officers’ attitude; e.g., hostile or accusatory versus “restrained and noncoercive.”30
NUMBER OF OFFICERS
The presence of several officers at the scene is somewhat coercive. But unless they surrounded the suspect or were otherwise in close proximity, this circumstance is not a strong indication of coercion.31
ARREST, HANDCUFFS
That the suspect had been arrested or was handcuffed is relevant, but not significant.32 As the Supreme Court observed, “[C]ustody alone has never been enough to demonstrate a coerced confession or consent to search.”33
DRAWN WEAPONS
Consent to search given at gunpoint will usually be involuntary 34 unless the following circumstances existed: (1) the officer had good reason for drawing the weapon, (2) the weapon was reholstered before consent was sought, and (3) the circumstances were not otherwise coercive.35
REFERENCES TO SEARCH WARRANTS
A remark by officers as to the existence, issuance, or necessity of a search warrant may constitute evidence of coercion depending on the context:
“WE HAVE A WARRANT”: Consent is involuntary if officers falsely said or implied that they possessed a warrant or that one had been issued. As the Supreme Court observed in Bumper v. North Carolina, “When a law enforcement officer claims authority to search a home under a warrant, he announces in effect that the occupant has no right to resist the search. The situation is instinct with coercion—albeit colorably lawful coercion.”36 “WE DON’T NEED A WARRANT”: Consent is involuntary if officers said or implied that, although they were asking for consent, they did not need it.37 “[T]here can be no effective consent,” said the Ninth Circuit, “if that consent follows a law enforcement officer’s assertion of an independent right to engage in such conduct.”38
“WE WILL SEEK A WARRANT”: Consent is not involuntary if officers merely told the suspect they would “seek” or “apply for” a search warrant if consent was refused.39 As the court explained in People v. Gurtenstein,40 an officer’s statement that “he would go down and apply for a search warrant” could not be considered coercive because he “was merely telling the defendant what he had a legal right to do.” Similarly, in U.S. v. Faruolo 41 an FBI agent told the defendant that if he refused to consent to a search of his house the agents would secure the premises and apply for a warrant. In rejecting the argument that this comment constituted coercion, the court said that, on the contrary, it was “a fair and sensible appraisal of the realities facing the defendant Faruolo.”
“WE WILL ‘GET’ A WARRANT”: If officers told the suspect that they would “get” or “obtain” a warrant if he refused to consent (as if warrants were issued on request), his consent should not be deemed involuntary if officers did, in fact, have probable cause for a warrant.42 As the Ninth Circuit explained, “[C]onsent is not likely to be held invalid where an officer tells a defendant that he could obtain a search warrant if the officer had probable cause upon which a warrant could issue.”43 Similarly, the Seventh Circuit observed in U.S. v. Duran, “Although empty threats to obtain a warrant may at times render a subsequent consent involuntary, the threat in this case was firmly grounded.”44
A REFUSAL IS A CONFESSION
Coercion is likely to be found if officers said or implied that, under the law, a refusal to consent is the same as a confession of guilt. This occurred in Crofoot v. Superior Court in which an officer detained a suspected burglar named Stine. Stine was carrying a “bulging” backpack and, in the course of the detention, the officer told him that he “shouldn’t have any objections to my looking in the backpack if he wasn’t doing anything.” In ruling that Stine’s subsequent consent was involuntary and that stolen property in the backpack should have been suppressed, the Court of Appeal said this: “[I]mplicit in the officer’s statement is the threat that by exercising his right to refuse the search Stine would be incriminating himself or admitting participation in illegal activity.”45
In a similar but somewhat less obvious scenario, an officer will ask a detainee if he is carrying drugs, weapons or other contraband. When the detainee says no, the officer will say or suggest that if he was telling the truth he would certainly have no objection to a search. Although this is not an unusual practice, we were unable to find any California case in which this precise subject was addressed. There are, however, at least two federal circuit cases in which the courts ruled that consent given under such circumstances may be voluntary if the officers made it clear to the detainee that he was free to reject their request.46
In a third variation on this theme (and probably the most common), the officer will omit asking the suspect if he is carrying contraband, and simply ask if he has “any objection” to a search. Of all three approaches, this is plainly the least objectionable.
For example, in Gorman v. United States 47 an FBI agent asked a robbery suspect if he had “any objection” to a search of his motel room, and the suspect said “go ahead.” In ruling that the agent’s words did not constitute a threat, the First Circuit explained that consent is not involuntary merely because the suspect faced the following dilemma: If he consented, the evidence would likely be found. But if he refused, it “would harden the suspicion [of guilt] that he was trying to dispel.”
NO SANE CRIMINAL WOULD VOLUNTARILY CONSENT:
Defendants sometimes attempt to prove they did not voluntarily consent by asserting that no lucid criminal would freely agree to a search that might uncover proof of their guilt. As noted earlier, however, these arguments are routinely rejected because there are several logical reasons why a criminal would freely do so.
Circumstantial evidence of voluntariness
Even if there was some circumstantial evidence of coercion, the suspect’s consent may be deemed voluntary if there was some overriding circumstantial evidence of voluntariness,48 which often consists of one or more of the following:
“YOU CAN REFUSE”: Officers are not required to notify a suspect that he has a right to refuse to consent,49 but it is a relevant circumstance.50 Thus in United States v. Mendenhall the Supreme Court observed that “the fact that the officers themselves informed the respondent that she was free to withhold her consent substantially lessened the probability that their conduct could reasonably have appeared to her to be coercive.”51
OFFICERS’ MANNER
A courteous attitude toward the suspect is highly relevant because it would ordinarily communicate to him that the officers were seeking his assistance, not demanding it. Thus it would be relevant that the officers displayed a “pleasant manner and tone of voice that is not insisting,”52 as opposed to one that was “officious and authoritative.”53
“ASKING” IMPLIES A CHOICE
The fact that officers asked the suspect for consent to search is, itself, an indication that he should have known he could have refused the request. As the California Supreme Court observed, “[W]hen a person of normal intelligence is expressly asked to give his consent to a search of his premises, he will reasonably infer he has the option of withholding that consent if he chooses.”54
SUSPECT SIGNED CONSENT FORM
It is relevant that the suspect signed a form in which he acknowledged that his consent was given voluntarily.55 But an acknowledgment will have little or no weight if he was coerced into signing it.56
SUSPECT WAS COOPERATIVE
That the suspect was generally cooperating with the officers, or that he suggested the officers conduct a search of his property is a strong indication that his consent was voluntary.57
SUSPECT INITIALLY REFUSED
It is relevant that the suspect initially refused the officers’ request or that he permitted them to search only some things, as this tends to demonstrate his awareness that he could not be compelled to consent.58
EXPERIENCE WITH POLICE, COURTS
Another example of circumstantial evidence of voluntariness is that the suspect had previous experience with officers and the courts. Thus, in People v. Coffman the California Supreme Court observed that, “given Marlow’s maturity and criminal experience (he was over 30 years old and a convicted felon at the time of the interrogation) it was unlikely Marlow’s will was thereby overborne.”59
MIRANDA WAIVER
Giving the suspect a Miranda warning before seeking consent has a slight tendency to indicate the consent was voluntary. A Miranda warning, said the Court of Appeal, “was an additional factor tending to show the voluntariness of appellant’s consent.”60
Suspect’s mental state
So long as the suspect answered the officers’ questions in a rational manner, consent is not apt to be involuntary merely because he was under the influence of drugs or alcohol, had a mental disability, was uneducated, or was emotionally upset or distraught. As the Eighth Circuit noted, “Although lack of education and lower-than-average intelligence are factors in the voluntariness analysis, they do not dictate a finding of involuntariness, particularly when the suspect is clearly intelligent enough to understand his constitutional rights.”61 Nevertheless, a suspect’s lack of mental clarity may invalidate consent if a court finds that officers obtained authorization by exploiting it.62
Scope and Intensity of Search
Before beginning a consensual search, officers must understand what they may search and the permissible intensity of the search. This requirement will be easy to satisfy if the suspect authorized a search of a single and indivisible object, such as a pants pocket or cookie jar. But in most cases they will be searching something (especially a home or car) in which there are containers, compartments, or separate spaces. So, how can officers determine the permissible scope of such a search?
Actually, it is not difficult because the Supreme Court has ruled that, in the absence of an express agreement, the scope and intensity of a consent search is determined by asking: What would a reasonable person have believed the search would encompass?63 As the Court put it, “The standard for measuring the scope of a suspect’s consent under the Fourth Amendment is that of objective reasonableness—what would the typical reasonable person have understood by the exchange between the officer and the suspect?”64 In this section, we will discuss how the courts answer this question.
Scope of the search
The “scope” of a search refers to physical boundaries of the search and whether there were any restrictions as to what places and things within these boundaries may be searched.65 As we will now discuss, scope is usually based on what the officers told the suspect before consent was given.
OFFICERS SPECIFIED THE OBJECT OF SEARCH
If officers obtained consent to search for a specific thing or class of things (e.g., drugs), they may ordinarily search any spaces and containers in which such things may reasonably be found.66 As the Tenth Circuit put it, “Consent to search for specific items includes consent to search those areas or containers that might reasonably contain those items.”67 For example, because drugs, weapons, and indicia can be found in small spaces and containers,68 the permissible scope of a search for these things in a home would include boxes, briefcases, and the various compartments in household furniture.69 Or, if officers were searching for such things in a car, the scope would include a paper bag and other containers,70 the area behind driver’s seat and door panels,71 a side panel compartment,72 behind the vents,73 under loose carpeting,74 the trunk,75 under the vehicle,76 the area between the bed liner and the side of the suspect’s pickup.77 Note that if the suspect authorized a search for “anything you’re not supposed to have,” officers may interpret this as consent to search for drugs.78
OFFICERS SPECIFIED THE NATURE OF CRIME
Instead of specifying the type of evidence they wanted to search for, officers will sometimes seek consent to search for evidence pertaining to a certain crime. If the suspect consents, the scope of the search would be quite broad because the evidence pertaining to most crimes frequently includes small things such as documents, clothing, weapons, and ammunition. Thus in People v. Jenkins the court ruled that, having obtained consent to search for evidence in a shooting, officers could search a briefcase because it “is obviously a container that readily may contain incriminating evidence, including weapons.”79
SCOPE NOT SPECIFIED
If neither the officers nor the suspect placed any restrictions on the search, or if they did not discuss the matter, the search must simply be “reasonable” in its scope. As the Eleventh Circuit explained, “When an individual gives a general statement of consent without express limitations, the scope of a permissible search is not limitless. Rather it is constrained by the bounds of reasonableness: what a police officer could reasonably interpret the consent to encompass.”80 Officers may, however, infer that a suspect who authorizes an unrestricted search had authorized them to look for evidence of a crime which, as noted, frequently consists of things that are very small.81
SEARCHING CONTAINERS IN SEARCHABLE AREAS
While conducting a search that is otherwise lawful in its scope and intensity, officers may ordinarily open and search any containers in which the sought-after evidence might reasonably be found.82 A container may not, however, be searched if it reasonably appeared to be owned, used, controlled, and accessed exclusively by someone other than the consenting person. This exception is discussed in the accompanying article, “Third Party Consent.”
Intensity of the search
The term “intensity” of the search refers to how thorough or painstaking it may be. But if, as is usually the case, the officers and suspect did not discuss the subject, the search must simply be “reasonable” in its intensity, as follows:
A “THOROUGH” SEARCH
Officers may presume that the suspect was aware they would be looking for evidence of a crime and would therefore be conducting a “thorough” search.83 As the court observed in U.S. v. Snow, “[T]he term ‘search’ implies something more than a superficial, external examination. It entails looking through, rummaging, probing, scrutiny, and examining internally.”84 But, as noted below in “Length of search,” officers may not be permitted to conduct a thorough search if they implied that they only wanted to conduct a quick or cursory one.
NOT DESTRUCTIVE
It would be unreasonable for officers to interpret consent to search something as authorization to destroy or damage it in the process. Thus, in discussing this issue in Florida v. Jimeno, the United States Supreme Court said, “It is very likely unreasonable to think that a suspect, by consenting to the search of his trunk, has agreed to the breaking open of a locked briefcase within the trunk, but it is otherwise with respect to a closed paper bag.”85 Similarly, in U.S. v. Strickland 86 a suspect gave officers consent to search “the entire contents” of his car for drugs. During the search, an officer noticed some things about the spare tire that caused him to think it might contain drugs. So he cut it open. His suspicions were confirmed (the tire contained ten kilograms of cocaine), but the court ruled the search was unlawful because “a police officer could not reasonably interpret a general statement of consent to search an individual’s vehicle to include the intentional infliction of damage to the vehicle or the property contained within it.”
In contrast, in People v. Crenshaw 87 the Court of Appeal ruled that an officer did not exceed the permissible intensity of a search for drugs in a vehicle when he unscrewed a plastic vent cover to look inside. This was because the officer “did not rip the vent from the door; he merely loosened a screw with a screwdriver and removed it.”
LENGTH OF SEARCH
The permissible length of a consent search depends mainly on how large an area must be searched, the difficulties in searching the area and its contents (e.g. heavily cluttered home), the extent to which the sought-after evidence can be concealed, and whether the officers claimed they would be conducting only a cursory search. For example, in People v. \$48,715 88 a Kern County sheriff ’s deputy found almost \$80,000 in cash during a consent search of a pickup truck that had broken down near Bakersfield. In the subsequent appeal of a forfeiture order, the driver argued that the search was too lengthy, but the court pointed out that the contents of the pickup included large bags of pasture seed and several suitcases, and that a “typical reasonable person” in the driver’s position “would have expected that [the deputy] intended, in some manner, to inspect the contents of the seed bags and the suitcases. Thus, the seizure would be extended and the search would be extensive.”
In contrast, in People v. Cantor 89 the court ruled that a search of a car took too long because, in obtaining consent, the officer had asked the driver, “Nothing illegal in the car or anything like that? Mind if I check real quick and get you on your way?” The entire search lasted about 30 minutes but court ruled it was excessive because a 30-minute search cannot reasonably be classified as “real quick.”
CONDUCTING A PROTECTIVE SWEEP
Officers who have lawfully entered a home to conduct a consent search may conduct a protective sweep of the premises if (1) they reasonably believed there was someone hiding on the premises who posed a threat to them or the evidence, and (2) this belief materialized after they entered; i.e., they must have not entered with the secret intention of conducting an immediate sweep.90
CONSENT TO “ENTER” OR “TALK”
If officers obtained consent to enter a home (“Can we come inside?”), they have the “latitude of a guest”91 which generally means they may not wander into other rooms,92 immediately conduct a protective sweep;93 or immediately arrest an occupant.94
SEARCH BY K-9
Officers who have obtained consent to search a car for drugs or explosives may use a K9 to help with the search unless the suspect objects.95 As the Ninth Circuit observed, “Using a narcotics dog to carry out a consensual search of an automobile is perhaps the least intrusive means of searching.”96
CONDUCTING MULTIPLE SEARCHES
When officers have completed their search, they may not ordinarily conduct a second search because, as the Court of Appeal observed, consent to search “usually involves an understanding that the search will be conducted forthwith and that only a single search will be made.”97
Consent withdrawn
The consenting person may modify the scope of consent or withdraw it altogether at any time before the evidence was discovered.98 In such cases, the following legal issues may arise.
EXPRESS AND IMPLIED WITHDRAWAL
A withdrawal or restriction of consent may be express or implied. However, neither an express nor implied withdrawal will result unless the suspect’s words or actions unambiguously demonstrated an intent to do so. As the Court of Appeal explained, “Although actions inconsistent with consent may act as a withdrawal of it, these actions, if they are to be so construed, must be positive in nature.”99 For example, the courts have ruled that the following words or actions sufficiently demonstrated an unambiguous intent to withdraw or restrict consent:
• After officers had searched the outer pockets of a backpack, and just before they were about to search the inside pockets, the suspect said, “Leave them alone.”100
• After the suspect consented to a search of his home, an officer went outside to call for backup; while she was on the radio, the suspect shut and locked the front door.101
• When asked for the keys to the trunk of his car, a suspect who had consented to a search of it threw the keys into some bushes.102
• An officer who was conducting a consent search of a woman’s apartment was about to enter her bedroom when the woman “raced in front of the officer and started to close the partially open door.”103
In contrast, the courts have ruled that the following words or conduct were too ambiguous to constitute a withdrawal of restriction of consent:
• A suspect in a hate crime who had consented to a search of his home initially tried to mislead officers as to the location of his home.104
• A person who had consented to a search of his home said he was uncertain as to his address.105
• A suspect verbally consented but refused to sign a consent form.106
• After the occupants of a car consented to a search of the vehicle, they refused to tell the officers how to open a hidden compartment the officers had discovered.107
SECURING THE PREMISES
Even if the suspect withdrew his consent, officers may secure the premises pending issuance of a search warrant if they reasonably believed there was probable cause for a warrant.108
Consent By Trickery
Obtaining consent to enter a home by means of a ruse or other misrepresentation is legal—most of the time. That is because consent, unlike a waiver of constitutional rights, need not be “knowing and intelligent.”109 But, as we will discuss, there are limits that seem to be based mainly on whether the courts thought the officers’ conduct was unseemly.
CONSENT FOR ILLEGAL PURPOSE
The most common type of consent by trickery occurs when a suspect invites an informant or undercover officer into his home to plan, commit or facilitate a crime; e.g. to buy or sell drugs. Although the suspect is unaware of the visitor’s true identity and purpose, the consent is valid because a criminal who invites someone into his home or business for an illicit purpose knows he is taking a chance that the person is an officer or informant. As the Supreme Court explained, “A government agent, in the same manner as a private person, may accept an invitation to do business and may enter upon the premises for the very purpose contemplated by the occupant.”110
For example, in Lopez v. United States 111 a cabaret owner in Massachusetts, German Lopez, tried to bribe an IRS agent who had figured out that Lopez was cheating on his business taxes. One day, the agent came to the cabaret and suggested that he and Lopez meet privately in Lopez’s office to discuss the bribe. Lopez agreed and their subsequent conversation was surreptitiously recorded and used against Lopez at his trial. He appealed his conviction to the Supreme Court, arguing that the recording of the conversation should have been suppressed because the agent had “gained access to [his] office by misrepresentation.” The Court disagreed, saying that the IRS agent “was not guilty of an unlawful invasion of [Lopez’s] office simply because his apparent willingness to accept a bribe was not real. He was in the office with [Lopez’s] consent.”
Perhaps the most famous of all the trickery cases is Hoffa v. United States 112 in which Teamsters boss Jimmy Hoffa was being tried in Nashville on charges of labor racketeering. One of Hoffa’s associates was Edward Partin, a federal informant.
While the trial was underway, Hoffa permitted Partin to hang out in a hotel room that Hoffa was using as a command post. Among other things, Partin overheard Hoffa saying that they were “going to get to one juror or try to get to a few scattered jurors and take their chances.” The racketeering trial ended with a hung jury, but Hoffa was later convicted of attempting to bribe one of the jurors.
On appeal to the United States Supreme Court, Hoffa argued that Partin’s testimony should have been suppressed because, even though Hoffa had consented to Partin’s entries into his room, his consent became invalid when Partin misrepresented his true mission. Of course he did, but the Court ruled it didn’t matter because “Partin did not enter the suite by force or by stealth. He was not a surreptitious eavesdropper. Partin was in the suite by invitation, and every conversation which he heard was either directed to him or knowingly carried on in his presence.”
Note that some untrusting criminals still think they can protect themselves from such trickery by simply refusing to admit a suspected undercover agent into their homes unless he first expressly denies that he is a cop (“You gotta say it else you ain’t comin’ in”). This is pure urban legend.113 As the Ninth Circuit observed, “If a lie in response to such a question made all evidence gathered thereafter the inadmissible fruit of an unlawful entry, all dealers in contraband could insulate themselves from investigation merely by asking every person they contacted in their business to deny that he or she was a law enforcement agent. This is not the law.”114
CONSENT FOR LEGAL PURPOSE
The rules on trickery are not so permissive if the undercover officer or informant was neither a friend nor associate of the suspect but, instead, had gained admittance by falsely representing that he needed to come inside for some legitimate purpose. As the Ninth Circuit explained, “Not all deceit vitiates consent. The mistake must extend to the essential character of the act itself … rather than to some collateral matter which merely operates as an inducement. . . . Unlike the phony meter reader, the restaurant critic who poses as an ordinary customer is not liable for trespass”115 For example, consent to enter a suspect’s home has been deemed ineffective when undercover officers claimed they were deliverymen, building inspectors, or property managers; or if the officers obtained consent by falsely stating they had received a report that there were bombs on the premises.116
There is also a case winding its way through the federal courts in which FBI agents disrupted the internet connection into a villa at Caesar’s Palace that had been rented by a suspect in an illegal gambling operation. An agent then gained admittance to the room by posing as a technician who needed to come in and restore the service. While inside, the agent videotaped various instrumentalities of this type of crime, and the video was later used to convict the suspect. In light of the cases discussed earlier, this could be trouble.
There is, however, an exception to this rule: If a house was for sale and the owner or his agent had an open house, an entry by an undercover officer is not invalid merely because the officer was not really interested in buying the house.117 This is because the whole purpose of an open house is to get people to come in, look around, and maybe become interested. And that’s just what the officer did. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.01%3A_Consent_Searches.txt |
“American criminals have a long tradition of armed violence.”1
The statistics are chilling: Over 93% of the officers killed in the line of duty since 1968 were killed by gunfire. And since 1995 2 most of these shootings occurred when the officers were detaining or pursuing the killer.3
And yet, neither of these statistics is surprising. After all, with a thriving underground market for firearms, it has become increasingly likely that a detainee will have one; and that he’ll try to use it if he thinks he is about to be arrested, especially if he is a two or three striker.4
In addition, the very nature of detentions puts officers in a precarious position. As the United States Supreme Court pointed out, a detention “involves a police investigation at close range, when the officer remains particularly vulnerable.”5 And even though the detainee is technically under the officer’s “control” in the sense that he is not free to leave, the Court noted that he still might “reach into his clothing and retrieve a weapon.”6 The Ninth Circuit captured the essence of the problem when it said:
It is a difficult exercise at best to predict a criminal suspect’s next move, and it is both naïve and dangerous to assume that a suspect will not act out desperately despite the fact that he faces the barrel of a gun.7
To help reduce this danger, the Supreme Court ruled that officers may conduct warrantless pat searches of detainees to determine whether they are carrying a weapon “and to neutralize the threat of physical harm.”8 There is, however, one restriction—and it’s a big one: they may do this only if they have reason to believe that the detainee is armed or dangerous.
The question has been asked: Why can’t officers pat search all detainees? It’s a legitimate question, especially considering that the “armed or dangerous” requirement was established 40 years ago when weapons and violence were much less prevalent than they are now.9 Still, there are reasons for not permitting indiscriminate pat searches. As the Supreme Court observed in the landmark case of Terry v. Ohio, the pat search is a “sensitive area of police activity”10 which “must surely be an annoying, frightening, and perhaps humiliating experience.”11 The Court went on to say:
[I]t is simply fantastic to urge that [a pat search] performed in public by a policeman while the citizen stands helpless, perhaps facing a wall with his hands raised, is a “petty indignity.” It is a serious intrusion upon the sanctity of the person, which may inflict great indignity and arouse strong resentment, and it is not to be undertaken lightly.12
Consequently, it is essential that officers understand when pat searches are, and are not, permitted. And that is the subject of the first half of this article. In the second half, we will discuss the other important limitation on pat searches: the permissible scope of the search. Taking note of these fundamental restrictions, the Court in Terry said, “[O]ur inquiry is a dual one—whether the officer’s action was justified at its inception, and whether it was reasonably related in scope to the circumstances which justified the interference in the first place.”13
Before we begin, however, we must acknowledge that officers will sometimes encounter situations in which they reasonably conclude that a pat search is necessary even though the grounds for it are questionable, or maybe even nonexistent. Or they might have reason to believe that it would be too dangerous to follow the required procedure. In either situation, officers should do what they think is necessary for their safety, and not worry too much about whether the search will stand up in court. As the California Court of Appeal observed, “Ours is a government of laws to preserve which we require law enforcement officers—live ones.”14
“ARMED OR DANGEROUS”
As noted, pat searches are permitted only if officers reasonably believe that the detainee is presently armed or dangerous. But unless they actually see a weapon, or unless the detainee is outwardly hostile, this determination must be based on circumstantial evidence.15 What circumstances are considered significant? And how do the courts evaluate them? These are the questions we will now examine.
General principles
ARMED OR DANGEROUS
In Terry, the Court said that pat searches are permitted only if officers reasonably believed that the detainee was armed “and” dangerous. Almost immediately, however, the lower courts understood that the use of the conjunctive “and” was an unfortunate lapse—that pat searches would be justified whenever officers reasonably believed that a detainee was armed or dangerous. After all, it is apparent that every suspect who is armed with a weapon is necessarily dangerous to any officer who is detaining him, even if the detainee was cooperative and exhibited no hostility.16
Furthermore, although the courts still routinely quote Terry’s “armed and dangerous” language, they understand that a pat search will be justified if officers reasonably believed that a detainee constituted an immediate threat, even if there was no reason to believe he was armed.17 As the Sixth Circuit put it, “The focus of judicial inquiry is whether the officer reasonably perceived the subject of a frisk as potentially dangerous, not whether he had an indication that the defendant was in fact armed.”18
THE “REASONABLE OFFICER” TEST
To determine whether an officer reasonably believed that a detainee was armed or dangerous, the courts employ the “reasonable officer” test. Specifically, they permit pat searches if the threat would have been apparent to a reasonable officer in the same situation.19 As the Eighth Circuit put it, “[T]he facts must be such that a hypothetical officer in exactly the same circumstances reasonably could believe that the individual is armed and dangerous.”20
It is therefore immaterial that the officer testified that he did not feel “threatened” or “scared.”21 But it is also immaterial that the officer believed in good faith that a pat search was justified.22 Again, what matters is how the circumstances would have appeared to an objective observer.
THE NEED FOR FACTS
A determination that a suspect was armed or dangerous must be based on specific facts.23 Feelings, hunches, and unsupported conclusions are irrelevant.
“ROUTINE” PAT SEARCHES
Because facts are required, pat searches can never be conducted as a matter of routine.24 In fact, judges will usually conclude that an officer has no understanding of the law if he testifies that he always or usually pat searches the people he detains.25 For example, the courts have summarily invalidated pat searches when the officer, when asked why he searched the defendant, replied as follows:
• “Standard procedure, officer’s discretion and my training.”26
• “Pat down everyone that I talk to, for safety reasons.” 27
• “Officer safety and because [the suspect] may have been armed.” 28
• “As far as I am concerned, anybody I stop could possibly have a weapon on them.” 29 In contrast, in People v. Juarez the court noted that the officer “testified that he was always in fear of harm when questioning a detained suspect but not that he always and without articulable reason allayed that fear by a frisk.” 30
TRAINING AND EXPERIENCE
The courts may consider an officer’s opinion, based on training and experience, as to whether certain facts or circumstances demonstrated a legitimate threat.31
TOTALITY OF CIRCUMSTANCES
The courts will take into account all of the relevant circumstances surrounding the encounter—the total atmosphere. As the Seventh Circuit observed, “[T]he standard is whether the pat-down search is justified in the totality of circumstances, even if each individual indicator would not by itself justify the intrusion.”32
For example, in People v. Avila the court pointed out, “All of these factors, although perhaps individually harmless, could reasonably combine to create fear in a detaining officer. The [pat search] test does not look to the individual details in its search for a reasonable belief that one’s safety is in danger; rather it looks to the totality of the circumstances.”33 Similarly, the court in People v. Satchell noted that, while none of the various circumstances clearly demonstrated a threat, when considered as a whole “there was something fishy in the situation and the officers were certainly entitled to contemplate the possibility of violence.”34
POSSIBILITY OF AN “INNOCENT” EXPLANATION
A pat search will not be invalidated merely because there might also have been an “innocent” or non-threatening explanation for the circumstances.35
“CLOSE” CASES
Finally, in close cases the courts are apt to uphold an officer’s determination that a detainee was armed or dangerous. As the Court of Appeal put it, “The judiciary should not lightly second-guess a police officer’s decision to perform a pat down search for officer safety.”36
Having discussed the general principles, we will now look at the circumstances that are relevant in determining whether it is reasonable to believe that a detainee is armed or dangerous.
Nature of crime under investigation
Grounds for a pat search will automatically exist if the suspect was detained to investigate a crime that is closely linked to weapons or violence,37 such as the following:
DRUG SALES
At the top of the list of “armed or dangerous” crimes is drug trafficking. As the Court of Appeal observed in People v. Simpson, “Illegal drugs and guns are a lot like sharks and remoras. And just as a diver who spots a remora is well-advised to be on the lookout for sharks, an officer investigating cocaine and marijuana sales would be foolish not to worry about weapons.”38 Or, as the court pointed out in People v. Thurman:
Rare is the day which passes without fresh reports of drug related homicides, open street warfare between armed gangs over disputed drug turf, and police seizures of illicit drug and weapon caches in warranted searches of private residences and other locales.39
Consequently, officers may pat search any detainee who is reasonably believed to be a drug dealer.40 In addition, as discussed later, officers who are executing a warrant to search a residence for drugs are also permitted to pat search everyone on the premises.
VIOLENT CRIMES
A pat search is, of course, also warranted if the detainee was reasonably suspected of having committed a crime of violence, such as murder, assault with a deadly weapons, robbery, or carjacking.41
BURGLARY
A suspected burglar may be pat searched because burglars often carry weapons or tools that could serve as weapons.42 As the Court of Appeal observed, “It is reasonable for an officer to believe that a burglar may be armed with weapons, or tools such as knives and screwdrivers which could be used as weapons, and that a pat-down search is necessary for the officer’s safety.”43
CAR THEFT
Because car thieves also frequently carry tools, they too may be pat searched.44
VEHICLE PURSUITS
Officers may pat search all occupants of a vehicle that has been stopped following a pursuit, regardless of the initial justification for the stop.45
TRAFFIC VIOLATIONS
While traffic stops are inherently dangerous, the likelihood that a violator is armed or dangerous is too remote to justify a pat search.46 As the court said in U.S. v. Brown, “Although the confrontation between a police officer and a citizen stopped for a traffic violation can be fraught with danger, this fact alone does not justify a patdown.”47
A bulge
A bulge under the detainee’s clothing will warrant a pat search if it might have been caused by a conventional weapon or an object that could readily be used as a weapon. As the Ninth Circuit pointed out, “[W]e have given significant weight to an officer’s observation of a visible bulge in an individual’s clothing that could indicate the presence of a weapon.”48 In determining whether a bulge appeared to constitute a threat, the following circumstances are relevant, oftentimes determinative:
SIZE AND SHAPE
A pat search will always be warranted if the size and shape of the bulge was consistent with the size and shape of a weapon.
HEAVY OBJECT
As discussed later, officers who are conducting a pat search may remove objects that feel hard to the touch. Consequently, officers may ordinarily pat search a suspect if there was reason to believe that the bulge under his clothing was caused by a heavy object. For example, in People v. Miles the court ruled a pat search was justified because “the officer saw an exaggerated bulge in defendant’s left jacket pocket and that the jacket ‘swung pretty freely’ in the officer’s direction. Because of the bulge and the manner in which the jacket swung, the police officer knew it was some type of heavy object, possibly a gun.”49
LOCATION OF THE BULGE
A suspicious bulge is even more cause for alarm if it was located in a place where weapons are commonly concealed; e.g., at the waist, in a pants or jacket pocket.50 For example, in upholding a pat search in People v. Brown, the court noted that the officer’s decision to pat search the defendant “was based on his observation of a bulge under [defendant’s] jacket and his experience that weapons are commonly carried under clothing in that approximate location of the waistband.”51
HIDING THE BULGE
A bulge is especially suspicious if the suspect was attempting to keep it hidden from officers. For example, in People v. Superior Court (Brown) the court noted, among other things, “[D]efendant was holding his hands clasped together in front of a bulge in the waistband in the middle of his waist . . . .”52
MAKING A GRAB
A bulge takes on even more significance if the suspect suddenly reached for it.53
Furtive gestures
A so-called “furtive gesture” is a movement by a suspect, usually of the hands or arms, that, (1) reasonably appeared to have been made in response to seeing an officer or a patrol car;54 and (2) was secretive in nature, meaning that it appeared the suspect did not want the officer to see what he was doing. A furtive gesture is, of course, a concern because of the possibility that the suspect may be attempting to hide or retrieve a weapon.
Nevertheless, the courts will not uphold a pat search simply because an officer testified that the suspect made a “furtive gesture.” This is mainly because “furtiveness” is highly subjective, plus the term “furtive gesture” has been overused (and occasionally abused) by officers to the point that judges have become skeptical whenever they hear it.
Instead, officers must explain exactly what the suspect did and why it appeared threatening, or at least suspicious.55 For example, in People v. King 56 a San Diego police officer was on patrol in an area plagued by gang activity when he stopped a car for expired registration. As he walked up to the car, he saw the driver, King, “reach under the driver’s seat” and do something that caused a sound—a sound that the officer described as “metal on metal.” In ruling that the officer’s subsequent pat search was lawful, the court noted that, “in addition to King’s movement, we have the contemporaneous sound of metal on metal and the officer’s fear created by the increased level of gang activity in the area.”
In the following examples, note how the officers elaborated, at least somewhat, on the detainee’s actions:
• He “lifted himself up from the seat with both arms in his rear portion of his body behind his back, both arms went up and down rapidly.”57
• He “reached back inside the car toward his waistband.”58
• He “clutched his stomach as he got out of the car, as if he were trying to keep something held against the front part of his body.”59
• The officer “noticed Edmonds reaching under the driver's seat as though he were attempting to conceal something. ‘I saw the Defendant lean all of the way forward,’ he recalled, ‘almost ducking out of my sight. I could see his head above the dashboard, and then I saw him lean back, up, seated upright in the vehicle.’”60
• “[The officer] noticed the driver lean to the right as if to conceal or obtain something.”61
• “[D]efendant crouched forward and placed his left hand toward the lower middle portion of his body. Defendant fumbled with his left hand in the right front portion of his body.”62
• “[T]he officers saw appellant reach into the back of his waistband and secrete in his hands an object which he had retrieved.”63
• “[The officer] saw two passengers in the truck making ‘quick and furtive movements’ below the dashboard.”64
Sudden movement
A sudden movement by a detainee may justify a pat search, especially a reaching movement. As the Ninth Circuit explained, “We have also considered sudden movements by defendants, or repeated attempts to reach for an object that was not immediately visible, as actions that can give rise to a reasonable suspicion that a defendant is armed.”65 Thus, in upholding pat searches, the courts have noted the following:
• “When defendant [a suspected street-level drug dealer] turned toward the patrol car and placed his hand inside his jacket, [the officer] believed that he was reaching for a weapon.”66
• “When defendant [a suspected heroin dealer] suddenly put his hand into the bulging pocket, [the officer] reasonably believed he was, or could be, reaching for a weapon.”67
• After the detainee produced an ID card from his rear pocket, the officer saw him “make a sudden gesture with his right hand to his left T-shirt pocket.”68
• The officer testified that “all three suspects alighted from the vehicle almost simultaneously. They all got out on us . . . ”69
• “Just after [the officer] started the search around defendant’s waistband, defendant abruptly grabbed for his outside upper jacket pocket.”70
• “Upon the officers’ approach, defendant lunged forward thrusting his right hand into one of the bag's open pockets.”71
• “When the officer approached the defendant he reached into his right rear pocket and appeared to be trying to get something out, and it was a jerking motion as though he were trying desperately to get something out of his pocket.”72
• “Appellant was combative and reached towards the front of his pants several times.”73
As we discuss later, when a detainee suddenly reaches into a location where weapons are commonly concealed, officers may usually dispense with the pat search procedure and immediately reach inside.
Refusal to comply
A detainee’s refusal to comply with an officer’s request or command may indicate defiance, which is certainly a relevant circumstance. For example, in People v. Superior Court (Brown) the court ruled a pat search of a detainee was warranted largely because the officer “twice called to defendant to stop but defendant without hesitation or turning around continued walking away from him.”74
A refusal to comply is especially likely to justify a pat search if the objective of the officer’s request or command was to restrict the detainee’s ability to secretly obtain a weapon. For example, in Adams v. Williams the United States Supreme Court ruled that an officer was justified in conducting a protective search of the defendant because, among other things, “[W]illiams rolled down his window, rather than comply with the policeman’s request to step out of the car so that his movements could more easily be seen.”75 Some other examples:
• After twice ignoring the officer’s command to raise his hands, the defendant “turned his back” and started to walk away.76
• “[A]ppellant refused to drop the object in his hands when asked to do so by the police officers.”77
• “[The officer] asked Ratcliff to show what he had in his pocket, but he did not comply.”78
• “Haynie also failed to obey [the officer’s] orders to spread his legs and keep his head facing forward.”79
• “[The FBI agent] ordered Bell to put his hands on the dashboard of the car. Bell did not move his hands from their position on his lap or thighs. The agent repeated his command to no avail.”80
• “Frank’s starting for his pockets again, after being told to take his hands out, provided an additional factor justifying a pat down search for weapons.”81
• “The deputy asked defendant to put the [fanny pack] on the hood of the patrol car, but defendant put it on the ground.”82
Detainee’s mental state
HOSTILE, AGITATED
A detainee’s overt hostility toward officers or an agitated mental state are both highly relevant. For example, in People v. Michael S. officers who had detained a juvenile for mildly suspicious behavior testified that he “started breathing very rapidly, hyperventilating, and became boisterous and angry and very antagonistic [and] clenched and unclenched his fists” and was “borderline combative.” In ruling the subsequent pat search was justified, the court noted that the defendant “displayed aggressive conduct and was either unable or unwilling to control himself.”83
Similarly, in U.S. v. Michelletti the court ruled that a pat search was justified because “Michelletti, a large and imposing man, was heading straight toward [the officer] with a ‘cocky,’ perhaps defiant attitude and his right hand concealed precisely where a weapon could be located.”84
It is also relevant that the detainee, although not overtly hostile at the time, had a history of hostility toward officers. For example, in Amacher v. Superior Court the Court of Appeal upheld a pat search mainly because the officer “personally had words with petitioner when he stopped him for a traffic violation. He knew that petitioner had had numerous hostile run-ins with other officers, and that petitioner had little or no respect for law enforcement officers.”85
NERVOUSNESS
A detainee’s display of nervousness has little relevance unless it was extreme or unusual.86 This occurred in U.S. v. Brown in which the court noted, among other things, that the detainee’s demeanor “was more nervous than one would expect in a routine traffic stop,” plus he kept “repeatedly glancing back towards the car in question.”87
UNDER THE INFLUENCE
A detainee who is under the influence of alcohol or drugs may be considered dangerous if his behavior was unpredictable, or if he was otherwise unable to control himself.88
Criminal history, gang affiliation
A detainee’s criminal history (especially involving violence or weapons) is another circumstance that will be considered.89 For example, in People v. Bush the court noted that the defendant “had a history of violence, possession of weapons and was reported to be a kick-boxer.”90
It is also relevant that the detainee was a known gang member or affiliate.91 For example, in U.S. v. Flett the court ruled that a pat search was warranted because, among other things, the officer knew that the detainee was a member of “a national motorcycle gang which had violent propensities, including charges of using firearms, assault and resisting arrest.”92 Similarly, in U.S. v. Garcia one of the reasons the court upheld the pat search of the defendant was that he was a known gang member, and the officer had testified that, “based on his training and experience he knew that guns are often part of the gang environment.” The court added, “In our society today this observation resonates with common sense and ordinary human experience.”93
Presence during execution of drug warrant
As noted earlier, officers may ordinarily pat search anyone who is lawfully detained to investigate drug sales. This is because of the close connection between guns and drug trafficking. For this reason, the United States Supreme Court has also ruled that officers who are executing a warrant to search a residence for drugs may pat search everyone who is on the premises when they arrive.94
For example, in People v. Thurman 95 officers in Vallejo had just entered a home to execute a warrant to search for drugs when they saw Thurman sitting on a sofa in the living room. An officer then patted him down and, in the process, discovered rock cocaine. Although Thurman had done nothing to indicate he posed a threat to anyone, the court ruled the pat search was justified because of the significant potential for violence in these situations. Said the court, “That appellant’s posture, at that moment, was nonthreatening does not in any measure diminish the potential for sudden armed violence that his presence within the residence suggested.”
For the same reasons that justify pat searching the occupants of drug houses, the California Supreme Court has ruled that officers may also detain people who arrive on the premises while the search is underway, at least if the manner of their arrival indicates they live there or are otherwise closely associated with the occupants.96
Nature of location
HIGH CRIME AREA
The fact that a detention occurred in an area where crime, gang, or drug problems are prevalent is a relevant circumstance,97 but it will not automatically justify a patdown.98 As the U.S. Court of Appeals put it, “The police do not have carte blanche to pat down anyone in a dangerous neighborhood.”99 Or, as the court explained in People v. King, “[T]he fact that an area involves increased gang activity may be considered if it is relevant to an officer’s belief that the detainee is armed and dangerous. While this factor alone may not justify a weapon search, combined with additional factors it may.”100
DESERTED AREA
It is relevant that the detention occurred in a place where there were few, if any, other people around. This is mainly because the lack of witnesses and potential assistance to the officer may motivate the detainee to take chances that he would not otherwise have taken.101
NIGHTTIME, DARKNESS
The fact that a detention occurred in a dark or relatively dark place is a circumstance that indicates increased danger because officers may not be able to see the detainee’s hands, movements by the detainee’s companions, or potential weapons nearby.102 As the court observed in People v. Satchell, “The area was dark and preparatory movements by defendant and his two companions might easily go unnoticed.”103 That the detention occurred in a dark location may be especially significant if the officers were outnumbered, or if their duties prevented them from giving their full attention to the detainee.104
Some courts have indicated there is increased danger when a detention occurs at night.105 It is not clear whether these courts meant that increased danger resulted from darkness or whether they view nighttime detentions as inherently dangerous, even if they occur in well-lighted places. In any event, if officers or prosecutors cite “nighttime” as a factor indicating increased danger, they should explain why this is so.106
Tips from citizens, informants
A pat search will be warranted if officers received a tip from a citizen or a tested informant that the detainee is currently carrying a concealed weapon. For example, in Adams v. Williams 107 a tested police informant approached a Connecticut police sergeant at about 2:15 A.M. and said that a man who was sitting inside a car parked nearby “had a gun at his waist.” The United States Supreme Court ruled that the officer’s subsequent protective search of the man was lawful, noting that the informant “was known to him personally and had provided him with information in the past.”
On the other hand, a tip from an anonymous or untested informant would not justify a pat search unless there was some reason to believe his information was accurate. For example, in Florida v. J.L. 108 an anonymous person called the Miami-Dade police department’s non-emergency number and reported that a “young black male” wearing a plaid shirt was standing at a certain bus stop and that he was carrying a gun. When officers arrived they saw a man who matched the description given by the caller. So they pat searched him, and found a gun. But the United States Supreme Court ruled the search was unlawful because there was simply no reason to believe the informant was reliable.
Said the Court:
All the police had to go on in this case was the bare report of an unknown, unaccountable informant who neither explained how he knew about the gun nor supplied any basis for believing he had inside information about J.L.
Other circumstances
COMPANION ARRESTED, ARMED
The question arises: If two people are detained together, can both of them be pat searched if officers reasonably believed that one of them was armed or dangerous? Some federal courts have resolved this question by devising a so-called “automatic companion” rule by which grounds to pat search a person are said to exist automatically if his companion was being arrested and was “capable of accomplishing a harmful assault on the officer.”109
The “automatic companion” rule may, however, be contrary to rulings of the United States Supreme Court that grounds to pat search cannot be based on mere proximity to someone else.110 It is, however, a circumstances that may be considered.111
POSSESSION OF OTHER WEAPON
If officers seize a gun, knife, or other conventional weapon from the detainee—even a legal weapon 112—they may pat search him to determine if he has any more.113
The question arises whether such a search would be justified if the detainee possessed a virtual weapon; i.e., an object that could conceivably be used as a weapon, such as a baseball bat or a hammer. Although this issue has not been resolved,114 it seems likely that a pat search would be upheld if, based on the nature of the object, its location or other circumstances, there was reason to believe it was being used as a weapon; e.g., baseball bat located between bucket seats. In one case, the court upheld a search based mainly on an officer’s observation of a “long black metal object” similar to a Mag flashlight in the detainee’s truck, and the object was “within eight or ten inches of [his] left hand.”115
DETAINEE’S SIZE
Although a pat search would not be justified merely because the detainee was “big,” his size would be a relevant circumstance if he was bigger than the officer.116
OFFICERS’ OUTNUMBERED
The courts often note whether the number of detainees was greater than the number of officers on the scene, the relevance being the increased danger to officers who are outnumbered.117
HAND IN POCKET
It is relevant that the detainee was keeping a hand inside a pocket, even though he did not do so suddenly or furtively.118
ASSUMING THE POSITION
A detainee’s act of spontaneously “assuming the position” for a pat search is a suspicious circumstance.119
PASSENGER IN POLICE CAR
The following is an exception to the “armed or dangerous” requirement: Any person may be pat searched before being transported in a police car if officers had a duty to transport him; e.g., he had to be removed from a freeway for his safety; he was a crime victim and he was going to be transported for showup.120 If, however, officers did not have a duty to transport him, a pat search is permitted only if they notified him that, (1) he had a right to refuse the ride, and (2) he would be pat searched if he accepted it.121
SEARCH PROCEDURE
Having grounds to pat search a detainee does not give officers free rein to search him from top to bottom, rummaging through pockets or under clothing, indiscriminately probing and prodding, pulling out anything that seems remotely suspicious. Nor may officers adjust his clothing to see what’s inside, or compel him to empty his pockets. As the Seventh Circuit observed, “An officer is not justified in conducting a general exploratory search for evidence under the guise of a stop-and-frisk.”122
Instead, officers must follow a carefully circumscribed procedure. As the U.S. Supreme Court noted:
The sole justification of the search is the protection of the police officer and others nearby, and it must therefore be confined in scope to an intrusion reasonably designed to discover guns, knives, clubs, or other hidden instruments for the assault of the police officer.123
This procedure, which has aptly been described as “coldly logical,”124 starts out relatively unobtrusively with a pat down of the outer clothing. If nothing suspicious is felt, the search must be terminated. But if officers detect an object that feels as if it might be a weapon or something that could readily be used as a weapon, they may take certain steps to confirm or dispel their suspicion.
Furthermore, if at any point during the process they develop probable cause to believe that the object is a weapon, they may disregard the procedure and immediately seize it. The subject of expedited emergency searches for weapons is discussed later in this article.
Step 1: “Any needles?”
In the past, the first step in conducting the search was to start patting the detainee’s clothing. But that changed with the increased threat of exposure to viruses resulting from concealed syringes, especially HIV and hepatitis. As a result, officers will often begin the process by asking the detainee if he has any needles or other sharp objects in his possession. Such a question does not impermissibly enlarge the scope of the search because it is reasonably necessary for officer safety. Nor does it require a Miranda waiver because, even if the detainee was “in custody,” it would fall within Miranda’s public safety exception.125
Of course, if he says he has a syringe in his possession, officers may remove it before beginning the patdown.126
Step 2: Patdown
The United States Supreme Court has explained that the search begins with a “careful exploration” of the outside surfaces of the detainee’s clothing, “all over his or her body.”127 The Court added, “A thorough search must be made of the [detainee’s] arms and armpits, waistline and back, the groin and area about the testicles, and entire surface of the legs down to the feet.”128
MANIPULATING OBJECTS
If officers detect an object under the detainee’s clothing, and if they cannot immediately rule out the possibility it is a weapon, they may grasp or otherwise manipulate it to try to determine what it is. As the court explained in People v. Lee:
Recognizing that the purpose of the pat-down is to dispel the suspicion that a person is armed, it seems to us that something more is contemplated than a gingerly patting of the clothing. [I]n order to rule out the presence of a weapon the officer may have to determine an object’s weight and consistency. We fail to see how this can be accomplished without using some sort of gripping motion.129 Officers may also manipulate any container in the detainee’s possession if it is, (1) large enough to hold a weapon, and (2) sufficiently pliable to permit officers to feel some or all of its contents; e.g., a purse or backpack.130 If, however, the container is not pliable, it appears that officers may not open it to determine its contents unless there was reason to believe it contained a weapon.
This occurred in People v. Hill in which the court noted, “The box was much heavier than an ordinary matchbox and the rattling sounds indicated that it contained metallic objects other than matches.”131 Note that a container may be pat searched even if the detainee had been separated from it after he was detained; e.g. officers had taken possession of it, or the detainee had put it on the ground.132
“EMPTY YOUR POCKETS”
In the absence of an emergency, officers may not bypass the pat down procedure by, for example, reaching inside the detainee’s clothing or pockets, by lifting up his clothing, or ordering him to empty his pockets.133
THE NEXT STEP
What happens next depends on what the officers felt. If they felt a weapon or something that reasonably felt like a weapon or an object that could be used as a weapon, they may remove it. If they felt nothing suspicious, the search must be discontinued.134 But if they felt something suspicious, and if they could not rule out the possibility that it was a weapon, they may go to step 3.
Step 3: Reaching inside
If officers detect something that feels like it might be a weapon, they will ordinarily have four options: (1) question the detainee about it,135 (2) lift up his clothing if that would help them determine what it is,136 (3) reach inside the detainee’s clothing and feel the object directly, or (4) reach in and remove it.137
Because officers are not required to employ the least intrusive means of determining the nature of a suspicious object,138 they may do any of these things. But they must have sufficient reason to believe that the object they felt could have been a weapon or an object that could have been used as a weapon.139 This is often the key issue in pat search cases because the courts, over the years, have become somewhat skeptical of such claims. As the California Supreme Court observed, “On occasion, the police have used the excuse that an object in a person’s pocket felt like a weapon to perform an exploratory search of the person’s clothing and empty the citizen’s pockets of everything.”140 For this reason, officers who are testifying at a suppression hearing must be very specific as to why the object felt as if it could have been a weapon. For instance, they should, if possible, describe its apparent weight, size, and shape.
Note that many of the circumstances that are relevant in determining whether officers reasonably believed that a detainee was armed or dangerous (discussed earlier) are also relevant in determining whether they reasonably believed that a concealed object under his clothing could be used as a weapon. For example, its location would be significant if it was a place where weapons are commonly secreted, or if it was a place in which objects are not ordinarily kept; e.g., inside the detainee’s boot.141 It would also be significant that the detainee had a history of carrying concealed handguns or engaging in gang violence, as this would rightly cause officers to view any suspicious object under his clothing with extra concern.
The question, then, is what types of objects will ordinarily justify a more intrusive search?
CONVENTIONAL WEAPONS
If the object felt like a conventional weapon, such as a gun or knife, officers may of course remove it.142 The following are examples:
• “a hard, rectangular object,” maybe a knife, “either folded or in a case” (hide-a-key box containing heroin)143
• “a hard object which [the officer] thought was a knife” (gun clip with live rounds)144
• “[s]ome type of heavy object, possibly a gun” (loaded revolver)145
• “a sharp object like a knife blade” (watch and bracelet)146
• “a hard object,” maybe a knife (straight-edge razor)147
• “a long hard object which could have been a knife” (long stem pipe)148
• “a bulge and a lump near the right jacket pocket,” maybe “the butt of a hand gun” (baggie containing 14 grams of rock cocaine)149
• “a cylindrical object several inches long in the defendant’s pocket . . . large enough that it could have been a knife” (drugs)150
VIRTUAL WEAPONS
A virtual weapon is an object that, although not commonly used to inflict bodily injury, is readily capable of doing so. Examples include baseball bats, razor blades, hypodermic needles, and bottles. If officers reasonably believe that an object they felt could have been a virtual weapon, they may remove it.151
ATYPICAL WEAPONS
An atypical weapon is an object that could conceivably harm someone, but is seldom used for that purpose; e.g., a ball point pen could be used as a stabbing instrument. The rules pertaining to atypical weapons are fairly strict: Officers may remove them only if they reasonably believed that removal was necessary for officer safety. 152 The key word here is “reasonably.” Officers cannot satisfy this requirement by engaging in “fanciful speculation” about an object’s potential dangerousness. 153 For example, in People v. Leib the court ruled that an officer’s act of removing a pill bottle from under the suspect’s clothing was unlawful because, said the court, “Even if a pill bottle could in some fanciful or extraordinary circumstances feel like a weapon, it is quite clear [the officer] knew the bottle was not in fact a weapon.” 154
HARD OBJECTS
If the object felt hard to the touch, officers may ordinarily remove it unless it clearly did not present a threat.155 For example, the courts have ruled that officers were justified in removing the following objects:
• a hard object which the officer could not identify because the suspect was wearing heavy jeans (three car keys solidly taped together)156
• a “hard rectangular object” (stack of 12 credit cards)157
• a “large, hard object” (brass door knob)158
• a “firm object 8-10 inches long” (two film cans containing marijuana)159
• two “bulky” objects inside the suspect’s boots (two baggies containing marijuana)160
• a “three-inch long, hard object” (matchbox)161
SOFT OBJECTS
Because most objects that can pose a threat to officers are hard to the touch, officers may remove a soft object only if they can cite specific facts that reasonably indicated it posed a real threat.162 As the California Supreme Court explained, “Feeling a soft object in a suspect’s pocket during a pat down, absent unusual circumstances, does not warrant an officer’s intrusion into a suspect’s pocket to retrieve the object.”163 For example, the courts have ruled that officers did not have sufficient justification to remove objects that felt as follows:
• “[s]ome soft bulky material” (a baggie of marijuana)164
• a “soft bulge” (a baggie of marijuana)165
• a “small round object” (a bottle of pills)166
• a “lump [maybe] pills” (LSD tablets in a plastic bag) 167
DRUGS
Under the “plain feel” rule, officers may remove an object that does not feel like a weapon if, (1) they have probable cause to believe it is an illegal drug or other contraband, and (2) probable cause existed at or before the time they determined it was not a weapon.168 The theory here is that, because probable cause gives officers a right to arrest the suspect, their seizure of the object is permitted as a search incident to arrest.169 For example, in People v. Thurman the court upheld the removal of drugs because, “simultaneous with the [officer’s] verification that the object was not a weapon” the officer realized that “the objects were pieces of rock cocaine contained in a baggie.”170
In determining whether probable cause existed, officers may consider how the object felt and any other relevant circumstances. As the Court of Appeal observed, “The critical question is not whether [the officer] could identify the object as contraband based on only the ‘plain feel’ of the object, but whether the totality of circumstances made it immediately apparent to [the officer] when he first felt the lump that the object was contraband.”171
For example, in People v. Dibb 172 an officer who was pat searching a detainee’s pants felt an object he described as “lumpy, and it had volume and mass.” He concluded that the lump was illegal drugs because, in addition to how it felt, officers who had just conducted a consensual search of the detainee’s fanny pack had found a gun clip, a gram scale having “the odor of methamphetamine,” a small plastic bag, and a beeper. In addition, the detainee had denied there was anything in his pocket, which was an obvious lie. In ruling the seizure of the lump (more methamphetamine) was lawful, the court said, “[The officer] had probable cause to arrest defendant when he first touched the object.”
Another application of the “plain feel” rule is found in People v. Lee.173 Here, an Oakland police officer on patrol in an area known for “high narcotic activity” lawfully detained a suspected drug dealer. While pat searching him, the officer felt some balloons in his jacket pocket. The officer testified that, as soon as he felt them, he recognized them as the heroin-filled variety and, just as important, he was able to articulate why: he had felt and seized heroin-filled balloons on at least 100 other occasions, and these balloons had an “unmistakable” feel associated with them; specifically, “each balloon has about the size and shape of a pea, with a textured rubber feeling and a bounce or bend that bounces back to its original shape.”
In ruling the seizure of the balloons was lawful, the court said, “[The officer’s] tactile perceptions coupled with the other facts known to him, furnished probable cause to believe that defendant’s jacket contained heroin, and therefore to immediately arrest him. At that point the officer was entitled to conduct a more thorough search as an incident of which the contraband was seized.”
In contrast, in People v. Valdez 174 the court ruled that an officer’s removal of a film canister from the suspect’s pocket was unlawful because the officer had no reason to believe it contained anything other than film.
REMOVING OTHER EVIDENCE
The “plain feel” doctrine is not limited to drugs. In fact, officers may remove any item they feel if, when they first felt it, they had probable cause to believe it was evidence of a crime.175 For example, in People v. Lennies H.176 a police officer in Vallejo detained a suspect in a carjacking that had occurred the day before in Sacramento. The suspect denied that he had the keys to the car, but the officer felt keys in his pocket when he pat searched him. So he reached in and retrieved them. In ruling the seizure of the keys was lawful, the court noted that although a key is not inherently illegal to possess, the officer “had probable cause to believe that the keys were evidence linking the minor to the carjacking at the time of the initial ‘plain-feel’ search.”
Similarly, in U.S. v. Bustos-Torres 177 a sheriff’s deputy felt a large amount of currency (\$10,000) in the pockets of a suspected drug dealer. In ruling that the seizure of the money was lawful, the court asked rhetorically, “Were the bills, by their mass and contour, immediately identifiable to the Sergeant’s touch as incriminating evidence?
Pondering the question with a dose of common sense, we believe they were.”
Emergency procedure
As noted earlier, officers are not required to follow the standard pat search procedure if they reasonably believe that an attack is imminent or if they have probable cause (as opposed to reasonable suspicion) that the detainee possesses a concealed weapon.178 Instead, they may take preemptive action, such as immediately going inside the clothing to locate and remove any weapons. This is permitted mainly because, as one court put it, “any other course of action would have been foolhardy and quite possibly suicidal.”179 The following are examples of circumstances that were found to justify an immediate search:
• The detainee jerked away when the officer started to pat search a bulge in the detainee’s pocket; then he told the officer, “You cannot search me without a warrant even if I have a gun.”180
• During a pat search, the detainee “abruptly grabbed for his outside upper jacket pocket; the officer could feel a “round cylindrical object” in the pocket.181
• During a contact, a suspected drug dealer “suddenly put his hand into [his] bulging pocket.”182
• A suspect who was detained in connection with a “shots fired” call, kept his left hand concealed in a jacket pocket; when the officer asked what he had had in the pocket, the suspect would not answer.183
• An officer who had detained a suspect for making threats saw what appeared to be the outline of a small handgun in the fanny pack he had been carrying.184
Officers may also bypass the standard procedure if they have probable cause to arrest the detainee, even though they had not yet done so.185 For example, if he had refused to comply with a safety-related command, officers would have probable cause to arrest him for a violation of Penal Code § 148 because he would have willfully resisted and obstructed an officer in the performance of his duties.186
In addition, officers may reach inside a detainee’s clothing or lift up his outer clothing without first pat searching him if he was wearing clothing that was so bulky or rigid that a pat down would not have revealed the presence of a weapon. As the court noted in People v. William V., “In light of William’s bulky clothes, [the officer] reasonably lifted [his] jacket to search his waistband.”187 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.02%3A_Pat_Searches.txt |
Every arrest must be presumed to present a risk of danger to the arresting officer.1
Taking a suspect into custody is an extremely “tense and risky undertaking.” 2 This is especially true when the crime is a felony because many of today’s felons are not only violent and well armed, they are often desperate. After all, they know they may be facing a lengthy prison term thanks to the various sentencing enhancements for felonies in California, including the three strikes law.
But even when the crime was not a high-stakes felony, there is always a threat of violence because people who are about to lose their freedom—even for a short time—may act impulsively and “attempt actions which are unlikely to succeed.”3 Taking note of this, the United States Supreme Court pointed out that “[t]here is no way for an officer to predict reliably how a particular subject will react to arrest or the degree of the potential danger.”4 Or, as the Ninth Circuit aptly observed, “It is a difficult exercise at best to predict a criminal suspect’s next move.”5
To help reduce these dangers, and also to make it harder for arrestees to destroy evidence, the U.S. Supreme Court ruled that officers who have made a custodial arrest may, as a matter of routine, conduct a type of search known as a search incident to arrest. Said the Court:
A custodial arrest of a suspect based on probable cause is a reasonable intrusion under the Fourth Amendment; that intrusion being lawful, a search incident to the arrest requires no additional justification. It is the fact of the lawful arrest which establishes the authority to search.6
Writing on this subject a few years ago, we happily mentioned in passing that this was an area of the law in which the courts had provided officers and prosecutors with rules that were easy to understand and apply. We had no idea that a sudden and dramatic upheaval was looming.
From Clarity To Perplexity
Because the circumstances surrounding most arrests are fluid, unpredictable, and dangerous, the courts have long understood that the rules pertaining to searches incident to arrest needed to be “easily applied and predictably enforced.”7 And so, in 1969 the United States Supreme Court ruled in the landmark case of Chimel v. California that officers who have made a custodial arrest may, as a matter of routine, search those places and things over which the suspect had “immediate control.” 8
The Court also broadly defined the term “immediate control” to encompass “the area from within which [the arrestee] might gain possession of a weapon or destructible evidence.” 9 (Today, this searchable area has become popularly known as “grabbing space” or “grabbing radius.”10 ) In explaining why it decided not to restrict these searches to explorations of the arrestee’s person, the Court pointed out that “[a] gun on a table or in a drawer in front of one who is arrested can be as dangerous to the arresting officer as one concealed in the clothing of the person arrested.”
In the following years, many of the lower courts reached the conclusion that it would be unwise to strictly interpret the terms “immediate control” and “grabbing” space to cover only those places and things to which the arrestee had actual control at the time of the search. This was because such an interpretation would produce two troublesome situations. First, an arrestee who did not want officers to search a place or thing in his immediate control when officers sought to arrest him would be given a powerful incentive to break away from the officers and separate himself from it, even a short distance. Second, officers who have arrested a suspect will often have significant safety reasons for restraining the arrestee or moving him a short distance away before searching those things that were under his control when he was arrested. For this reason, the courts would consistently rule that it would be imprudent to require that officers choose between conducting a search and taking reasonable safety precautions. Thus, comments such as the following would regularly appear in the cases:
• “[I]t does not make sense to prescribe a constitutional test that is entirely at odds with safe and sensible police procedures.”11
• “[I]t makes no sense to condition a search incident to arrest upon the willingness of police to remain in harms way while conducting it.”12
• “[I]f the police could lawfully have searched the defendant’s grabbing radius at the moment of arrest, he has no legitimate complaint if, the better to protect themselves from him, they first put him outside that radius.”13
But one type of arrest situation remained problematic: searches of vehicles incident to the arrest of the driver or other occupant. The problem was that these arrestees were almost always restrained in some manner outside the vehicle before the search began; e.g., handcuffed, surrounded by officers, locked in a patrol car. Consequently, some courts would rule that officers could not search the passenger compartment in these situations, while others would rule they could because, again, if something could have been searched legally one minute, it seems irrational to rule it could not be searched a few seconds later because the officers had taken reasonable safety precautions.
This dilemma was finally resolved by the United States Supreme Court in 1981. In its landmark decision in the case of New York v. Belton,14 the Court noted that these vehicle-search cases had become “problematic” because the lower courts had failed to provide officers with “a set of rules which, in most instances, makes it possible to reach a correct determination” of what places and things they may search. So, after noting that weapons and evidence inside “the relatively narrow compass of the passenger compartment” of an automobile are “in fact generally, even if not inevitably” within the arrestee’s reach at some point, the Court announced the following “bright line” rule: Officers who have made a custodial arrest of an occupant of a vehicle may search the passenger compartment—regardless of whether the arrestee had physical access to the vehicle when the search occurred.
Consequently, it soon became standard police procedure throughout the country that if officers could conduct the search immediately after the arrest, they should do so. But if there were matters that needed their attention beforehand, they could address them so long as there was no unnecessary delay. Here are two examples of circumstances that were found to justify searches of places and things that were not within the arrestee’s immediate control at the time of the search:
• Officers delayed searching the arrestee’s car until it had been towed from the scene of the arrest because “gunfire and subsequent crash of [their] car had attracted a crowd so large that extra policemen had to be summoned [to control] the mob that was forming.”15
• Officers delayed searching the arrestee’s car because they were dispatched to a priority auto accident.16
In contrast, a search would not be deemed contemporaneous with an arrest if the delay was not reasonably necessary; e.g., officers delayed the search for 30-45 minutes in order to question the arrestee.17
Arizona v. Gant: Back to uncertainty
For almost 30 years, Chimel and Belton provided officers and the courts with a coherent set of rules that clearly defined the parameters of these searches. But that changed in 2009 when a bare majority of the Supreme Court announced its opinion in the case of Arizona v. Gant. (Although Gant technically upended only those rules pertaining to vehicle searches, as we will discuss shortly, it effectively dismantled the entire structure of this area of the law and left it in a “confused and unstable” state.18) Stripped of all its verbiage and dissembling (and there was a lot of both), the Court’s decision in Gant prohibited all vehicle searches unless they occurred at a time when the arrestee was both unrestrained and sufficiently close to the vehicle that he might have been able to reach inside.
Because the Gant justices were presumably aware that officers never turn their backs on unrestrained arrestees—and not under any circumstances while preoccupied with a search—they must also have been aware that their decision would effectively abolish Belton searches and render Belton a nullity. And yet, for some curious reason they felt compelled to engage in blatant subterfuge and claim they had no intention of overturning Belton, even though they must have known that no one would believe them.19 As Justice Alito observed in his dissenting opinion: “Although the Court refuses to acknowledge that it is overruling Belton,” there “can be no doubt that it does so.”
While there is much to criticize about Gant, there is no escaping the fact that Belton and Chimel were occasionally producing strange results that were taxing the credibility of the courts. For instance, judges would sometimes uphold searches of places and things that were nowhere near the arrestee when the search occurred, so long as there was a theoretical—sometimes fanciful—possibility that he might have been able to reach it. In one such case, United States v. Tejada, the court ruled that although the arrestee was “[h]andcuffed, lying face down on the floor and surrounded by police,” and although it was unlikely that he would be able to make a “successful lunge” at anything, a search of the room in which he was arrested was warranted because the officers “did not know how strong he was, and he seemed desperate.” 20
As a result of such rulings, some courts started to express concern that this area of the law had become untethered. One of them pointed out that “where there is no threat to the officers because the suspect has been immobilized, removed, and no one else is present, it makes no sense that the place he was removed from remains subject to search merely because he was previously there.”21 Another observed that, “[a]s with most other legal doctrines, that of Chimel can be reduced to logical absurdity if one is so disposed.”22
True enough. But instead of fixing this particular problem, the Court in Gant effectively overturned or at least cast into doubt a wealth of thoughtful legal analysis—spanning nearly three decades—in which the lower courts had sought to balance the safety needs of officers and the privacy rights of arrestees.
Gant’s unresolved issues
Before we discuss the law as it exists today in the wake of Gant, it is necessary to address three issues that the Court neglected to address, issues that cannot be ignored in this article because they will be critical in determining the lawfulness of all four types of searches incident to arrest.
IS GANT LIMITED TO VEHICLE SEARCHES?
Although Gant technically restricts only vehicle searches incident to the arrest of an occupant, it is hard to avoid the conclusion that it will be interpreted as restricting all of the other types of searches incident to arrest, such as containers near the arrestee and homes in which the arrest occurred.23 That is because the privacy expectations in homes and many closed containers are significantly greater than those in the passenger compartments of cars.24 To put it another way, if something in a car cannot be searched because it was inaccessible to the arrestee, it is difficult to imagine a court ruling that a similarly inaccessible item could be searched if it were located in the arrestee’s home.25 Again quoting Justice Alito, “[T]here is no logical reason why the same rule [that applied to the arrests of vehicle occupants] should not apply to all arrestees.”
Furthermore, the Court in Gant phrased its ruling in sweeping terms that are flatly inconsistent with such a restricted interpretation. Here is an example: If there is no possibility that an arrestee could reach into the area that law enforcement officers seek to search, [the] justifications for the search-incident-toarrest exception are absent and the rule does not apply. In fact, there is already a California case— People v. Leal—in which the California Attorney General conceded that Gant applies equally to searches of homes.26 (In another case, it was argued that Gant even applied to pat searches; i.e., that officers should not be permitted to pat down any part of the suspect’s body unless they could prove it was immediately accessible to the arrestee. This silly argument was, however, rejected.27)
HOW MUCH ACCESS IS REQUIRED
Because officers need to have some idea of how much access is necessary before they can search an item near the arrestee, it might be assumed that the Gant Court would have provided some guidance. Instead, in the span of just a few pages it announced a test that was subsequently rendered unintelligible by a second test. And then it propounded a third test that differed somewhat from the first two. Specifically, at one point it said the test is access; i.e., a search is permitted if the arrestee had “access” to his car. Then it changed its mind and announced a more restrictive test: a search is permitted only if the arrestee was within actual “reaching distance” of the passenger compartment. And then it proclaimed that access and reaching distance were not enough—that the arrestee must also have been unsecured, which presumably meant that he must not have been handcuffed and otherwise restrained.
One of the first courts that tried to make sense of this gibberish was the Third Circuit which, having given up in its attempt to discern the correct test from the Court’s words, was forced to resort to a “close reading” of the text. And after having done so, it formulated the following hypothesis:
[T]he Court’s reference to a suspect being “unsecured” and being “within reaching distance” of a vehicle are two ways of describing a single standard rather than independent prongs of a two-part test. In later formulations of its holding, the Gant Court omitted any reference to whether Gant was secured or unsecured, and looked instead simply to Gant’s ability to access his vehicle.28
Thus, the court interpreted Gant as prohibiting searches of places and things if there was “no reasonable possibility” the arrestee might access it.
HOW STRICTLY WILL GANT BE INTERPRETED?
The last—and most uncertain—question is whether the courts will engage in “an aggressive reading of Gant”29 and ignore the large body of law—some of it from the Supreme Court itself—in which searches were upheld when they were “roughly” or “substantially” contemporaneous with the arrest.30
A related question is whether the courts will invalidate searches because there was some uncertainty as to whether the arrestee did, in fact, have access. In addressing this issue, it is hoped that the courts will take into account the D.C. Circuit’s observation that, because custodial arrests are dangerous, “the police must act decisively and cannot be expected to make punctilious judgments regarding what is within and what is just beyond the arrestee’s grasp.”31 It should be noted that three courts have already refused to apply Gant in a hypertechnical manner, having ruled that it did not prohibit a vehicle search when, although the arrestee had been restrained, there were other suspects who had immediate access to the vehicle.32
One last thing: On November 1, 2010, the Supreme Court decided to review the case of Davis v. U.S. in which it is expected to determine whether Gant must be applied retroactively.
Requirements
Having reviewed the state of the law, we will now examine the requirements for conducting these types of searches. Although there are four distinct searches incident to arrest, they all have the same basic requirements, as follows:
1. Lawful arrest: The suspect must have been lawfully arrested.
2. Custodial arrest: The arrest must have been custodial in nature.
3. Contemporaneous search: The search must have been contemporaneous with the arrest.
It should be noted that the first two requirements were not affected by Gant, which means they are fairly easy to understand. It was the third requirement—contemporaneousness—that is uncertain.
Lawful arrest
In the context of searches incident to arrest, an arrest is deemed “lawful” if officers had probable cause to arrest the suspect.33 This rule has several practical consequences.
SEARCH BEFORE ARREST
If officers had probable cause, some searches (especially pat downs) may be deemed incident to an arrest even though the suspect had not yet been arrested.34 As the Court of Appeal explained, “Once there is probable cause for an arrest it is immaterial that the search preceded the arrest.”35
OFFICERS UNSURE ABOUT PROBABLE CAUSE
If a court determines that the officers had probable cause, the “lawful arrest” requirement is satisfied even if they were unsure that it existed. “It is not essential,” said the court in People v. Le, “that the arresting officer at the time of the arrest or search have a subjective belief that the arrestee is guilty of a particular crime . . . so long as the objective facts, when fully determined, afford probable cause.”36
For example, in People v. Loudermilk 37 two Sonoma County sheriff ’s deputies detained a hitchhiker at about 4 A.M. because he matched the description of a man who had shot another man about an hour earlier in nearby Healdsburg. When the hitchhiker Loudermilk, claimed he had no ID, one of the deputies started searching his wallet and, just as he found some, Loudermilk spontaneously exclaimed, “I shot him. Something went wrong in my head.” Loudermilk contended that his admission should have been suppressed because it was prompted by the search of his wallet which, he contended, did not qualify as a search incident to arrest because one of the deputies testified he didn’t think he had probable cause to arrest Loudermilk for the shooting. The court said it didn’t matter what the deputy thought—what counts is what the court thought. And it thought the deputy had it.
ARREST FOR “WRONG” CRIME
If a court rules that officers arrested the suspect for a crime that was not supported by probable cause, the arrest will nevertheless be deemed “lawful” if there was probable cause to arrest him for some other crime.38 As the Tenth Circuit put it, “[T]he probable cause inquiry is not restricted to a particular offense, but rather requires merely that officers had reason to believe that a crime—any crime—occurred.”39
For example, in In re Donald L.40 a Martinez police officer detained a minor, Donald, at about 9 P.M. because he resembled a person who was suspected of having just cased a house for a burglary. The officer also noticed that Donald was carrying a “club type” instrument, so he patted him down and discovered rings, watches, and necklaces. Thinking it was loot from a recent break-in, the officer arrested him for burglary. Although it was later determined that the jewelry had, in fact, just been stolen from a nearby home, Donald contended that the search could not be upheld as incident to his arrest because the officer did not have probable cause to arrest him for burglary, at least before the jewelry was discovered. Even if that were true, said the court, it wouldn’t matter because the officer “had probable cause to arrest [Donald] for unlawful possession of a ‘billy’ or ‘blackjack.’”
Custodial arrest
The second requirement—that the arrest must have been “custodial”—means that the officers must have decided to transport the arrestee to jail, a police station, or other place of confinement or treatment; i.e., he will not be cited and released. This requirement was imposed because the main justification for these searches is the increased danger that necessarily results from the “extended exposure which follows the taking of a suspect into custody” and the “attendant proximity, stress and uncertainty.”41
For these reasons, an arrest will be deemed custodial regardless of whether the crime was “minor,”42 or that officers were aware that the suspect would immediately post bail or would otherwise be released after a short stay.43 For example, in People v. Sanchez 44 the defendant argued that a search of his pocket was unlawful because he had been arrested for merely being drunk in public. In summarily rejecting the argument, the court pointed out that “the officer testified he fully intended to book appellant into jail; he did not plan to release appellant.”
Because an arrest becomes “custodial” when officers decide to transport the arrestee, a search will also be permitted if officers had decided to take him to a detox facility, mental health facility, or hospital.45 Similarly, the arrest of a minor is custodial if he will be taken to school, home, a curfew center; or if he will be taken into protective custody.46
On the other hand, an arrest will not be deemed custodial if officers had decided not to transport the suspect or if they had not yet decided what to do. For example, in U.S. v. Parr 47 an officer in Portland, Oregon searched Parr after learning he was driving on a suspended license. Although the officer found stolen mail in the course of the search, and although he also had probable cause to arrest Parr for driving on a suspended license, he released him, having decided to submit the case to prosecutors. After Parr was charged with possessing stolen mail, he argued the search could not be upheld as a search incident to arrest because the officer did not take him into custody and, moreover, there was no evidence to suggest that he ever intended to do so. The court agreed, saying “it is not clear that the police action taken here is the type of ‘custodial arrest’ necessary to support a search incident to arrest.”
It should be noted that several California statutes require or authorize a custodial arrest depending on the nature of the crime and other circumstances. For example, the law requires that officers book every person who was arrested for a felony or certain misdemeanors such as DUI, and misdemeanors that were reasonably likely to continue.48 What if officers transported the arrestee even though they were not authorized to do so by statute? In the case of Atwater v. City of Lago Vista the U.S. Supreme Court ruled that such an arrest is nevertheless “custodial” because it is the decision to transport the arrestee—not the statutory authority to do so—that justifies the search.49
For example, in People v. McKay 50 a Los Angeles County sheriff ’s deputy stopped McKay for riding a bicycle in the wrong direction on a street. Although McKay had verbally identified himself and also provided his date of birth, he had no ID in his possession so the deputy decided to take him into custody. He then conducted a search incident to the arrest and found a baggie of methamphetamine in one of McKay’s socks. On appeal to the California Supreme Court, McKay argued that the search could not qualify as a search incident to arrest because he had, in fact, satisfactorily identified himself and, therefore, the officer was required by state law to cite and release him. But the court ruled the search was lawful, saying, “[S]o long as the officer has probable cause to believe that an individual committed a criminal offense, a custodial arrest—even one effected in violation of state arrest procedures—does not violate the Fourth Amendment.”
This should not be interpreted to mean that the courts are encouraging officers to transport arrestees in violation of California state law. On the contrary, the California Supreme Court has said “we in no way countenance violations of state arrest procedure,” 51 and the United States Supreme Court noted that such conduct may demonstrate “extremely poor judgment.” 52
Contemporaneous Search
The third requirement for a search incident to arrest is that the arrest and search must have been contemporaneous. Although the word “contemporaneous” in common usage refers to situations in which two acts occur at about the same time, the courts have consistently ruled that the circumstances surrounding most arrests are much too erratic and unpredictable to require a strict succession of events. Instead, the United States Supreme Court ruled on two occasions that the arrest and search need only be “substantially” contemporaneous.53
And yet, as noted earlier, the Court in Gant seemed to downplay the importance of temporal proximity as it looked mainly to the physical proximity between the unrestrained arrestee and the place or thing that was searched. So the question arises: How will the lower courts resolve the apparent inconsistency between the established and somewhat-flexible requirement of “substantial” contemporaneousness and the seemingly rigid test imposed in Gant? Here are some thoughts.
SUBSTANTIAL PHYSICAL PROXIMITY
In determining whether an arrestee had sufficient access to the place or thing that was searched, it seems likely that the courts will continue to apply the following rules which, apart from making good sense, are consistent with the Court’s “substantiality” principle:
• LUNGING DISTANCE VS. GRABBING DISTANCE: While the area that is accessible to an arrestee is sometimes called “grabbing distance,”54 it should not be limited to places and things that were literally within his “wingspan.”55 Instead, it appears likely that the courts will continue to permit officers to search places and things that were within the arrestee’s “lunging” distance.56
• EXPECT IRRATIONALITY, NOT ACROBATICS: In determining whether something was within lunging distance, officers should be permitted to consider that arrestees may act irrationally—that their fear of incarceration may motivate them to attempt to reach places some distance away.57 As the D.C. Circuit observed, “A willful and apparently violent arrestee, faced with the prospect of long-term incarceration, could be expected to exploit every available opportunity.”58 Still, the place or thing “must be conceivably accessible to the arrestee—assuming that he was neither an acrobat nor a Houdini.”59
UNCERTAINTY AS TO ARRESTEE’S ACCESS
In the wake of Gant, it seems likely that one of the the most hotly contested issues will be whether a search should be invalidated because there was some uncertainty as to whether the arrestee did, in fact, have unfettered access to the place or thing that was searched. We hope, however, that the courts which face this issue will take into account that arrests are inherently dangerous and, to repeat the words of the D.C. Circuit, officers in the midst of making an arrest “cannot be expected to make punctilious judgments regarding what is within and what is just beyond the arrestee’s grasp.”60
For example, in the post-Gant case of United States v. Shakir 61 officers arrested Shakir on a warrant for bank robbery when he arrived in the lobby of a casino in Atlantic City. After handcuffing him, they searched a gym bag at his feet and found money that he had taken in another of his bank robberies. Shakir argued that the money should have been suppressed because he did not have actual access to the bag when it was searched. But the Third Circuit ruled the search was lawful, saying, “Although it would have been more difficult for Shakir to open the bag and retrieve a weapon while handcuffed, we do not regard this possibility as remote enough to render unconstitutional the search incident to arrest.”
IF THE ARRESTEE FLED
Before Gant, if the arrestee fled when officers tried to arrest him, most courts would rule that the officers could search places and things that were under his immediate control when they attempted to arrest him, plus places and things under his immediate control when he was taken into custody. They reasoned that it was not in the public interest to provide arrestees with a way to impede or prevent the discovery of incriminating evidence by defying or fighting with officers and thereby forcibly distancing themselves from it. Although it appears these searches would not be permitted under a strict interpretation of Gant, the courts might find that Gant did not repudiate the conventional wisdom upon which the earlier opinions were based.62
EMERGENCIES
As noted earlier, before Gant was decided the courts would usually uphold a search that was not contemporaneous with an arrest if officers needed to delay the search because of exigent circumstances. To date, the courts in three post-Gant cases have applied a variation of this principle and ruled that, although the arrestee did not have immediate access to the thing that was searched, the search was lawful because there were other unrestrained suspects who did.63 But this, too, has become a murky area of the law as the result of Gant.
Types of Searches
Officers who have made a lawful custodial arrest may, depending on the circumstances, conduct one or more of the following types of searches incident to arrest: (1) a search of the arrestee’s person, (2) a search of things within the arrestee’s immediate control, and (3) a limited search of the home in which the arrest occurred. Furthermore, if the arrest occurred inside a home, they may conduct a hybrid search that consists of a protective sweep of the area immediately adjoining the place of arrest. Finally, they may (albeit rarely) search the vehicle in which the arrestee was an occupant.
Searching the arrestee
When officers make an arrest, the first thing they will normally do is search the arrestee. This type of search should not be affected by Gant because the arrestee will necessarily have immediate control over everything on his person. While it might be argued that Gant would not permit a search if the arrestee had been handcuffed, such an argument would be fallacious because the handcuffs will necessarily be removed at some point. Furthermore, as the Fifth Circuit observed, “Albeit difficult, it is by no means impossible for a handcuffed person to obtain and use a weapon concealed on his person or within lunge reach.”64
Although the United States Supreme Court vaguely described the scope of these intrusions as “full” searches,65 the courts have interpreted the term as encompassing the following:
PAT SEARCH
Officers may, of course, pat search the arrestee, a procedure which the Supreme Court described as follows: “The officer must feel with sensitive fingers every portion of the prisoner’s body. A thorough search must be made of the prisoner’s arms and armpits, waistline and back, the groin and area about the testicles, and entire surface of the legs down to the feet.”66
SEARCHES OF CLOTHING
The Court also ruled that officers may conduct a “relatively extensive exploration” of the arrestee’s clothing, including his pockets.67 And because of the threat resulting from syringes, the Court of Appeal ruled that, before conducting the search, officers may ask the arrestee whether there are any needles or other sharp objects in his pockets or anywhere else on his person.68
SEARCHING CONTAINERS
Officers may search containers that the arrestee was carrying when the search occurred, such as a wallet, purse, backpack, pockets, cigarette box, pillbox, envelope.69
NO EXTREME SEARCHES
Officers may not conduct strip searches or any other exploration that is “extreme or patently abusive.”70 Furthermore, in the unlikely event that it becomes necessary to remove some of the arrestee’s clothing in order to conduct a full search, officers must do so with due regard for the arrestee’s legitimate privacy interests.71
Searching things nearby
In the past, officers could search all containers and other things that were within grabbing distance of the arrestee when the arrest occurred.72 Although Gant still permits officers to search things near the arrestee, these searches must now be limited to items that were reasonably accessible to him when the search occurred. That was the situation in U.S. v. Shakir, noted earlier, in which the court ruled that officers did not violate Gant when they searched a gym bag at the feet of the defendant because, “[a]lthough he was handcuffed and guarded by two policemen, Shakir’s bag was literally at his feet, so it was accessible if he had dropped to the floor.”73
In determining whether a place or thing was reasonably accessible to the arrestee at the time of the search, the following pre-Gant law is consistent with Gant and should still be valid:
CONTAINERS UNDER OFFICERS’ CONTROL
Because an arrestee has no control over a container at the moment that officers are searching it, it might be argued that all searches of containers are prohibited as the result of Gant. But the Supreme Court flatly rejected this “fallacious” theory in New York v. Belton 74 (which, as noted earlier, it did not overturn) and there is nothing in Gant to suggest that it intended to impose such an extreme rule.
CONTAINERS “IMMEDIATELY ASSOCIATED”
Nor is there anything in Gant to suggest that the Court was overturning another of its longstanding rules: that officers may search a container that was not under the arrestee’s immediate control if it was the type of property that is “immediately associated with the person of the arrestee”; e.g., purses.75
CONTAINERS TO GO
If the arrestee wants to take an item with him (e.g., a jacket), and if officers permit it, Gant would not restrict their ability to search it even if it was not under the arrestee’s immediate control when he was arrested or when the search occurred. This is because the item would presumably be returned to him at some point.76 Officers may not, however, compel an arrestee to take a certain item, then search it on the theory the search was incident to the arrest or was necessary for officer safety.77
SEARCHING PAGERS, CELL PHONES
Because so many arrestees carry pagers and cell phones nowadays, the question has frequently arisen: Can these searches be upheld as an incident to an arrest? Although it is questionable in light of Gant (mainly because there is no officer-safety justification 78) the California Supreme Court ruled on January 3, 2011 that cell phone searches fall under the Supreme Court’s warrant exception for containers that are “immediately associated with the person of the arrestee.”79 This means cell phones may be searched incident to an arrest even if the search occurred hours after the arrest occurred, and even though there was no threat that the information stored on the cell phone could be destroyed. The case is People v. Diaz 80 and we have posted a report on Online. Second, a search of cell phones and such things might be upheld under an exigent circumstances theory if (1) officers had probable cause to believe that telephone numbers, text messages, or other data stored in the device are evidence of a crime; and (2) officers reasonably believed that the data might be lost unless a search was conducted immediately; e.g., digitally-stored data might be automatically deleted as new calls are received.81
Searching vehicles
As discussed earlier, the Supreme Court in Gant ruled that officers may not search the passenger compartment of a vehicle incident to the arrest of an occupant unless there was a reasonable possibility that the arrestee had access to the passenger compartment when the search occurred.82 In those rare cases in which these types of searches are permitted, it appears that officers may search the entire passenger compartment, including all containers (regardless of whether the container was open or closed);83 and all storage areas, such as the glove box, console, and map holder.84 Officers may not, however, search the trunk or damage the car in the course of the search.85
Searching homes (Chimel searches)
The term “Chimel search” refers to a search of a place or thing inside a residence that was within the grabbing or lunging area of the arrestee. Prior to Gant, the courts ordinarily interpreted this to mean that officers could search places and things that were within this area at the time of the search. But, as we will now discus, that is likely to change.
POST-GANT LAW
For reasons discussed earlier, it is likely that the courts will rule that, pursuant to Gant, the search must be limited to places and things that were within the arrestee’s grabbing distance when the search occurred. For example, officers would be permitted to search under a bed on which the arrestee was lying,86 inside a duffel bag at the foot of a bed on which the arrestee was lying,87 under a sofa cushion that was two feet away from the unhandcuffed arrestee when the search occurred.88
Although there is authority for permitting a search of a place or thing that was not within the arrestee’s immediate control when there was good reason to move him away before starting the search,89 this authority appears to have been undermined by Gant.90
PRE-GANT LAW CONSISTENT WITH GANT
While the following rules predate Gant, they are probably still good law:
ARRESTS OUTSIDE THE RESIDENCE
A Chimel search will not be permitted if the arrest occurred outside the premises.91 As the United States Supreme Court observed, “If a search of a house is to be upheld as incident to an arrest, that arrest must take place inside the house, not somewhere outside—whether two blocks away, twenty feet away, or on the sidewalk near the front steps.”92
SEARCHING OTHER ROOMS
Even before Gant was decided, the courts would rule that officers may not routinely search beyond the room in which the arrest occurred.93 There is, however, an exception to this rule that will probably not be affected by Gant: if the arrestee requests permission to go into another room to, for example, obtain clothing or identification, officers may, in the words of the Supreme Court, stay “literally at [his] elbow at all times.”94 Furthermore, if officers have permitted the arrestee to enter another room, they may search places and things in that room that are within his grabbing area. This is because, as the California Supreme Court pointed out, an arrestee’s request to move to another room might be “a ruse to permit him to get within reach of a weapon or destructible evidence.”95 But such a search would not be permitted if officers compelled the arrestee to enter the room without good cause.96
Vicinity sweeps of homes
A vicinity sweep is a type of search incident to arrest that is limited to a cursory inspection of spaces “immediately adjoining the place of arrest from which an attack could be immediately launched.”97 It is apparent that vicinity sweeps will not be affected by Gant because the threat presented by hidden friends or associates in the vicinity will exist regardless of whether the arrestee had been handcuffed or removed from the immediate area.98 To put it another way, an officer’s act of moving the arrestee from the arrest site will not reduce the threat caused by any lurking companions
Vicinity sweeps are similar to Chimel searches in that both may be conducted as a matter of routine, meaning that officers will not be required to prove there was reason to believe that any dangerous people were nearby.99 There are, however, two important differences. First, the sole objective of a vicinity sweep is to locate people, not weapons or evidence. Consequently, officers may search only those places and things in which “unseen third parties” might be hidden;100 e.g., officers are not permitted to open drawers or look under rugs.
Second, there is a difference in scope between grabbing area and spaces “immediately adjoining the place of arrest.” Although both cover a fairly small amount of territory, the area “immediately adjoining” the place of arrest will usually extend well beyond the arrestee’s grabbing distance. This is because an arrestee can only grab so far; while a friend, relative, or accomplice might be able to launch a sneak attack from any hidden space in the immediate vicinity.101 (In reality, an accomplice could launch an attack from virtually anywhere on the premises. But, like many types of warrantless searches, vicinity sweeps represent an imperfect compromise between the safety interests of officers and the privacy interests of others.)
For example, in U.S. v. Curtis 102 officers in Washington, D.C. lawfully arrested Curtis and Melvin in the living room of their two-bedroom apartment. While two officers guarded the arrestees, two other officers looked inside a living room closet, the adjoining kitchen, and two bedrooms located “down the hall.” In the course of the sweep, they found drugs in the bedrooms. While the court had no problem with the officers looking into the closet and the kitchen, it ruled that the search of the bedrooms was unlawful because “[t]here was no justification for a sweep of such remote areas.” | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.03%3A_Searches_Incident_to_Arrest.txt |
PETITIONER RESPONDENT
Merle R. Schneckloth Robert Clyde Bustamonte
LOCATION
Location of Car Search
DOCKET NO. DECIDED BY
71-732 Burger Court
LOWER COURT
United States Court of Appeals for the Ninth Circuit
CITATION
412 US 218 (1973)
ARGUED
Oct 10, 1972
DECIDED
May 29, 1973
GRANTED
Feb 28, 1972
ADVOCATES
Robert R. Granucci for petitioner
Stuart P. Tobisman for the respondent, pro hac vice, by special leave of Court
Facts of the case
A police officer stopped a car that had a burned out license plate light and headlight. There were six men in the car, including Robert Clyde Bustamonte. Only one passenger had a drivers license, and he claimed that his brother owned the car. The officer asked this man if he could search the car. The man said, “ Sure, go ahead.” Inside the car, the officer found stolen checks. Those checks were admitted into evidence at Bustamonte’s trial for possessing checks with the intent to defraud. A jury convicted Bustamonte, and the California Court of Appeal for the First Appellate District affirmed. The court reasoned that consent to search the car was given voluntarily, so evidence obtained during the search was admissible. The California Supreme Court denied review. Bustamonte filed a petition for a writ of habeas corpus, which the district court denied. The U.S. Court of Appeals for the Ninth Circuit reversed, holding that consent is not voluntary unless it is proven that the person who consented to th e search knew he had the right to refuse consent.
Question
1. Did the court of appeals err when it held that the search of the car was invalid because the state failed to show consent given with knowledge that it could be withheld?
2. Should claims relating to search and seizure be available to a prisoner filing a writ of habeus corpus?
Conclusion
6–3 Decision for Schneckloth Majority Opinion by Potter Stewart
FOR AGAINST
Stewart
White
Powell
Burger
Blackmun
Rehnquist
Douglas
Brennan
Marshall
Yes, No answer. Justice Potter Stewart, writing for a 6 -3 majority, reversed. The Supreme Court held that whether consent is voluntary can be determined from the totality of the circumstances. It is unnecessary to prove that the person who gave consent knew that h e had the right to refuse. The Fourth Amendment protection against unreasonable searches and seizures does not require a knowing and intelligent waiver of constitutional rights. Because the Fourth Amendment claims had no merit, the Court did not reach the second question. Justice Lewis F. Powell also concurred, stating that the main question should be whether Bustamonte had a fair opportunity to raise his Fourth Amendment claims. Chief Justice Warren E. Burger and Justice William H. Rehnquist joined in the concurrence. Justice Harry A. Blackmun concurred, agreeing with the majority and noting it was unnecessary to reach the issue discussed by Justice Powell.
6.05: United States v. Drayton
PETITIONER RESPONDENT
United States Drayton
DOCKET NO. DECIDED BY
01-631 Rehnquist Court
LOWER COURT
United States Court of Appeals for the Eleventh Circuit
CITATION
536 US 194 (2002)
ARGUED
Apr 16, 2002
DECIDED
Jun 17, 2002
ADVOCATES
Larry D. Thompson Argued the cause for the petitioner
Gwendolyn Spivey Argued the cause for the respondents
Daniel J. Pop eo et al. for the Washington Legal Foundation et al. as amici curiae urging reversal
Joshua L. Drat el et al. for the National Association of Criminal Defense Lawyers as amicus curiae urging affirmance
Richard Weintraub et al. for Americans For Effective Law Enforcement, Inc., et al. as amici curiae
Facts of the case
Christopher Drayton and Clifton Brown were traveling on a Greyhound bus. In Tallahassee, Florida, police officers boarded the bus as part of a routine interdiction effort. One of the officers worked his way from back to front, speaking with individual passengers as he went. The officer did not inform the passengers of their right to refuse to cooperate. As the officer approached Drayton and Brown, he identified himself, declared that the police were looking for drugs and weapons, and asked if the two had any bags. Subsequently, the officer asked Brown whether he minded if he checked his person. Brown agreed and a pat-down revealed hard objects similar to drug packages in both thigh areas. When Drayton agreed, a pat-down revealed similar objects. Both were arrested. A further search revealed that Drayton and Brown had taped cocaine to their legs. Charged with federal drug crimes, Drayton and Brown moved to suppress the cocaine on the ground that their consent to the pat-down searches was invalid. In denying the motions, the District Court determined that the police conduct was not coercive and Drayton and Brown's consent to the search was voluntary. In reversing, the Court of Appeals noted that bus passengers do not feel free to disregard officers' requests to search absent some positive indication that consent may be refused.
Question
Must police officers, while searching buses at random to ask questions and to request passengers' consent to searches, advise passengers of their right not to cooperate?
Conclusion
6–3 Decision for United States Majority Opinion by Anthony M. Kennedy
FOR AGAINST
Breyer
Kennedy
Scalia
Thomas
O’Conner
Rehnquist
Ginsburg
Souter
Stevens
No. In a 6-3 opinion delivered by Justice Anthony M. Kennedy, the Court held that the Fourth Amendment does not require police officers to advise bus passengers of their right not to cooperate and to refuse consent to searches. The Court reasoned that, although the officer did not inform the defendants of their right to refuse the search, he did request permission to search and gave no indication consent was required. Moreover, the Court noted, the totality of the circumstances indicated that the consent was voluntary. Justice David H. Souter, with whom Justices John Paul Stevens and Ruth Bader Ginsburg joined, dissented. "The issue we took to review is whether the police's examination of the bus passengers ... amounted to a suspicionless seizure under the Fourth Amendment. If it did, any consent to search was plainly invalid as a product of the illegal seizure," argued Justice Souter. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.04%3A_Schneckloth_v._Bustamonte.txt |
“[T]he items in question have been exposed to police view under unobjectionable circumstances, so that no reasonable expectation of privacy is breached by an officer’s taking a second look . . . ” U.S. v. Grill 1
When an arrestee is booked into jail, officers or jail staff will routinely examine and inventory most or all of his personal property. If they happen to find evidence in the process, it will ordinarily be given to investigators or stored in an evidence room.2 The rest will be kept in a property room for safekeeping. It might sit there for days, often months or longer.
At some point, investigators might want to take a second look at it. In many cases, they will be looking for something specific, whether it pertains to the crime for which the prisoner was arrested or some other crime. Oftentimes they just want to see if there is anything with evidentiary value that was overlooked when the prisoner was booked. In either case, the question arises: Is a warrant required?
At first glance, it might seem that a warrant would never be necessary because the property is in the lawful possession of a law enforcement agency or detention facility. Thus, the prisoner cannot reasonably expect his property is protected. This may, in fact, be the view of the United States Supreme Court which made the following observation in
U.S. v. Edwards:
[I]t is difficult to perceive what is unreasonable about the police’s examining and holding as evidence those personal effects of the accused that they already have in their lawful custody as the result of a lawful arrest.3
While this language seems to indicate that a warrant will never be required, elsewhere in Edwards the Court indicated that a warrant might be required in some situations, although it did not elaborate.4
So, what’s the law? As we will now explain, an analysis of Edwards and other cases leads to the conclusion that a warrant is not required to search an item if there is probable cause to believe it is evidence of a crime. If probable cause does not exist, a warrant is unnecessary if, (1) the item was “subject to search” during booking, and (2) the search was conducted in a reasonable manner.
IF PROBABLE CAUSE EXISTS
If officers have probable cause to believe that an item taken from a prisoner for safekeeping is evidence of a crime, they may seize it without a warrant. This is essentially because a prisoner does not enjoy a reasonable expectation of privacy as to seizable evidence of a crime that is in the lawful possession of a law enforcement agency.
The controlling case on this issue is Edwards 5 which resulted from the defendant’s arrest late one night as he was attempting to break into a post office in Ohio. When Edwards was booked, he was allowed to keep his clothing. Meanwhile, officers at the post office determined that the burglar had unfastened a window with a pry bar and, in the process, left “paint chips on the window sill and wire mesh screen.” Figuring that some of the chips would probably have stuck to the perpetrator’s clothing, they gave Edwards some jail garb and sent his clothes to the lab for analysis. As expected, the lab found bits of paint that matched the paint at the post office.
The Ohio Court of Appeals ruled the seizure of Edwards’ clothing was unlawful because it occurred after he had been booked. The Ohio Court of Appeals ruled the seizure of Edwards’ clothing was unlawful because it occurred without a warrant after the booking process had been completed. The United States Supreme Court disagreed, ruling the search was lawful regardless of when it occurred because the officers had probable cause. Said the Court:
It must be remembered that . . . the police had lawful custody of Edwards and necessarily of the clothing he wore. When it became apparent that the articles of clothing were evidence of the crime for which Edwards was being held, the police were entitled to take, examine, and preserve them for use as evidence, just as they are normally permitted to seize evidence of crime when it is lawfully encountered.
Similarly, in U.S. v. Oaxaca 6 two men were arrested shortly after they robbed a bank in the City of Commerce. When booked into the Los Angeles County Jail, they were allowed to keep their shoes. About six weeks later, investigators took the shoes from them without a warrant in order to compare them with the perpetrators’ shoes as shown in a surveillance video. They matched.
On appeal, the defendants argued the shoes should have been suppressed because the investigators did not have a warrant. The Ninth Circuit disagreed, saying:
Both the defendants and their shoes remained in lawful custody until the time when the shoes were taken for use as evidence. To require a warrant under these circumstances would be to require a useless and meaningless formality.
IF NO PROBABLE CAUSE
If investigators lack probable cause to conduct a warrantless search of a prisoner’s stored property, they may search it nevertheless if both of the following requirements are met: (1) they searched only those items that were actually searched or “subject to search” during booking or arrest; and (2) the search was conducted in a reasonable manner.
THE “SUBJECT TO SEARCH” TEST
Under the “subject to search” test, a warrant is not required to take a second look at items that were actually observed during a search incident to arrest or during booking, or items that could have been lawfully observed at either time.7 As the U.S. Supreme Court observed in Edwards:
[M]ost cases in the courts of appeals . . . have long since concluded that once the accused is lawfully arrested and is in custody, the effects in his possession at the place of detention that were subject to search at the time and place of his arrest may lawfully be searched and seized without a warrant even though a substantial period of time has elapsed between the arrest and subsequent administrative processing, on the one hand, and the taking of the property for use as evidence, on the other.8
Three things should be noted about the “subject to search” test. First, a second look is permitted even though there was no “first look,” so long as officers could have taken a first look when the suspect was booked or arrested.9 Second, because officers can lawfully look at virtually everything in an arrestee’s possession,10 the “subject to search” requirement is seldom an obstacle.11
Third, the “subject to search” test is actually more protective of the prisoners’ privacy than a rule permitting a second look only if officers did, in fact, see the item during booking or arrest. This is because such a rule would give the arresting officers and jail staff a perverse incentive to open every container and search everything they find to make sure that all of the prisoner’s property would be subject to a second look. As the Ninth Circuit noted in U.S. v. Burnette.
It is likely that, were we to require warrants for subsequent searches, police officers would routinely remove all items from containers seized at the time of the initial search and thereby insure that all items were discovered at that time. Thus, requiring a warrant for subsequent searches would be unlikely to provide any additional protection for individual privacy.12
Because the courts employ a “subject to search” test, the following items are subject to a second look without a warrant.
PROPERTY NOT INSIDE A CONTAINER
Articles that were not inside a container may be inspected because they were not only “subject to search,” they were actually seen— at least briefly—when they were seized, inventoried, or stored; e.g., clothing, rings, watches, keys.13 As the United States Supreme Court observed, “The seizure of an item whose identity is already known occasions no further invasion of privacy.”14
PROPERTY INSIDE A CONTAINER
Items that were inside a container may be searched if, (1) officers actually opened the container during booking or arrest and saw the contents, or (2) the contents of the container were subject to search when the prisoner was booked.15 As a practical matter, all property inside a container is subject to a second look because, as the United States Supreme Court observed, “[I]t is not unreasonable for police, as part of the routine procedure incident to incarcerating an arrested person, to search any container or article in his possession, in accordance with established inventory procedures.”16
MANNER OF SEARCHING
As noted, a “second look” search must be conducted in a reasonable manner. In determining whether such a search was reasonable, the courts look at, (1) whether the property was searched more than once and, if so, whether there was a good reason for conducting multiple searches; and (2) whether officers damaged or destroyed property in conducting the search.17
EXAMPLES
The following are examples of situations in which the courts ruled that a warrant was not required to take a second look at a prisoner’s property:
ROBBER’S RING: After the defendant was arrested for robbing a cab driver, investigators learned from the victim that the perpetrator was wearing a certain kind of ring. A booking inventory showed that the defendant was wearing a ring when he was arrested. Investigators retrieved the ring from property and showed it to the victim, who identified it. The ring, said the court, “did not have, nor can it acquire after booking, a vestige of privacy requiring a search warrant.”18
ROBBER’S RING: A Sacramento bank teller noticed that the man who was robbing her was wearing a “gold nugget ring.” When Davis was arrested for the robbery a few days later, he had two rings in his possession. During booking, the rings were put in a nylon bag. When an FBI agent learned that the teller had noticed that the robber was wearing a gold ring, he asked a police detective to see if there were any rings in Davis’s property. Checking the inventory sheet, the detective saw that the bag contained two rings, so he opened it and seized the rings—one of which was identified by the teller. The court ruled the warrantless seizure was lawful because the detective “did not conduct a search but merely retrieved items, lawfully obtained, that law enforcement knew were in its possession.”19
RAPIST’S SHOES: After Cheatham was arrested for rape, his clothes and shoes were “inventoried and stored in the jail’s property room.” Cheatham was also a suspect in another rape case in which the perpetrator left shoe prints at the scene. When investigators learned Cheatham was in custody, they obtained the shoes from the property room without a warrant, examined the tread, and determined they matched. In rejecting Cheatham’s argument that the shoes should have been suppressed because the officer did not obtain a warrant, the Washington Supreme Court said, “[O]nce an inmate’s personal effects have been exposed to police view in a lawful inventory search and stored in the continuous custody of the police, the inmate no longer has a legitimate expectation of privacy in the items free of further government intrusion.”20
KEYS: Thompson was arrested in Texas on drug charges. During booking, officers seized some keys, among other things. Several days later, an FBI agent went to the jail and arrested Thompson for stealing dynamite. The agent was aware that some keys had been booked into property, so he inspected them and, as the result, determined they opened a storage unit in which the dynamite had been found. The court ruled the agent did not need a warrant to inspect the keys, noting, “[The FBI agent was] not searching personal effects based on mere hunches that something of evidentiary value might be found. The police officer who had arrested Thompson had already informed the federal agent about the keys. The agent’s particularized search for the keys did not require a warrant.”21
KEYS: Two Symbionese Liberation Army members, Little and Remiro were arrested by Concord police for the murder of Oakland Schools Superintendent Marcus Foster. During booking, officers removed a set of keys from each of them. Later that day, the keys were turned over to an Oakland police officer who determined they opened the locks on some buildings connected to the SLA. In ruling the keys were seized lawfully, the Court of Appeal noted that an arrestee’s personal effects “like his person itself, are subject to reasonable inspection, examination, and test.”22
BAIT MONEY: After arresting Westover, detectives in Kansas City searched him and found \$621 which was later put into an envelope and stored in the police property room. Because Westover was also a suspect in two Sacramento bank robberies, officers later examined the money without a warrant and determined that some of the bills had been taken in the Sacramento holdup. In ruling a warrant was not required, the Ninth Circuit observed, “In taking the money, no one would suggest that at that instant a search warrant would be required to list the numbers on the bills. Thus, a search warrant to again look at the money already in police custody does not make sense.”23
ROBBER’S CLOTHES: Earls was arrested on an unspecified Vehicle Code violation and booked into jail. During booking, his clothing “was confiscated.” Several days later, FBI agents determined that Earls was a suspect in a Sacramento bank robbery. An agent obtained Earls’ clothing and sent it to the FBI lab for analysis. The lab found fibers that linked Earls to the robbery. Court: “During their period of police custody an arrested person’s personal effects, like the person itself, are subject to reasonable inspection, examination, and test.”24
MURDERER’S RING: LAPD detectives had probable cause to arrest Phillip Gunn for murder. When they learned that a man named Phillip Gunn was in jail on a cocaine possession charge they went there to see if the prisoner was the Gunn they were looking for. Gunn’s property had been stored in a transparent plastic bag. Inside the bag, they could see a ring which they apparently realized was similar to the ring worn by the murder victim. Before confirming that the prisoner was the murder suspect, they opened the bag and seized the ring. Later, they showed it to the victim’s wife who positively identified it. Said the court: “What the homicide investigators did in this case cannot be classified as either a search or a seizure within the meaning of the Fourth Amendment. The ring was lawfully in the custody of the police. Its storage in the plastic property bag was purely for convenience and safekeeping. No expectation of privacy was involved. The ring was no more in a place of privacy than if the booking officer had left it on the counter of the booking desk.”25
ADDRESS BOOK: A Scottsdale police officer arrested Holzman for using a stolen credit card in a department store. During a search incident to the arrest, the officer found an address book. He opened the book and noted it contained “a bunch of names and numbers,” but he did not read any of the entries. The address book was subsequently placed with Holzman’s other property in the jail property room. As the investigation continued, the officer developed probable cause to believe that Holzman was involved in widespread credit card scam. Consequently, he went back to the jail and took a closer look at the entries in the address book and discovered incriminating evidence. Said the court, “[T]he arresting officer legitimately examined the address book during the valid arrest of Holzman, and determined that it contained ‘a bunch of names and numbers.’ At that point appellant’s expectation of privacy in the contents of the book was significantly diminished.”26 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.06%3A_Taking_a_Second_Look_at_Prisoners_Property.txt |
“[D]rug use and violent crime in the schools have become major social problems.” 1
There are very few things that virtually everyone agrees on. But here’s one: Schools are places in which the students must be safe.2 School safety is not only essential for the students’ physical and emotional health, it is necessary in order to create an environment in which students can learn. As the California Supreme Court observed, “Teaching and learning cannot take place without the physical and mental well-being of the students.”3 To put it another way, “Without first establishing discipline and maintaining order, teachers cannot begin to educate their students.”4
An important part of this effort is eliminating drugs and weapons from school grounds. Another is keeping people off school property if they have no legitimate reason for being there. One of the difficulties in accomplishing these objectives is that they often require searches and detentions of students and others. And this can be dangerous.
As a result, many school districts now have their own police departments staffed by sworn officers.5 Another significant development is the school resource officer program in which law enforcement officers are assigned to work closely with school administrators. Over the years, these officers have become invaluable because they provide both an authoritative presence and a wealth of specialized knowledge on how to detect and combat crime on school grounds.
The courts have also assisted in this effort. As we will explain in this article, they have determined that it has become necessary to ease the restrictions on searches and detentions that occur on school grounds. As the court pointed out in People v. Randy G.:
[School officials] must be permitted to exercise their broad supervisory and disciplinary powers, without worrying that every encounter with a student will be converted into an opportunity for constitutional review.6
Searches on school grounds
School officers may search students and their property on school grounds if they have reasonable suspicion that the search will turn up evidence of a crime or a violation of school rules.7 As the United States Supreme Court explained:
Under ordinary circumstances, a search of a student by a teacher or other school official will be justified at its inception when there are reasonable grounds for suspecting that the search will turn up evidence that the student has violated or is violating the law or the rules of the school.8
Because only reasonable suspicion is required, a search will be upheld even though the probability of finding evidence is “considerably less” than a preponderance of the evidence; i.e., considerably less than a 50% chance.9 On the other hand, a search would be unlawful if it was based on “mere curiosity, rumor, or hunch.”10
Not surprisingly, searches for weapons are especially likely to be upheld because, as the Fourth Circuit observed, “Weapons are a matter with which schools can take no chances.”11 For example, in People v. Alexander B. 12 the dean of students at a high school in Los Angeles and two officers with the school’s police force were trying to defuse an encounter between the members of two gangs on the school grounds. As the tension mounted, one of the participants said, “Don’t pick on us. One of those guys has a gun.” As he said this, he gestured toward five or six students who had been standing around, “yelling and making gang signs.” Upon hearing this, the dean told an officer to “check the group over there. One of them is supposed to have a weapon.” When the officer ordered the students to sit on the curb, one of them, Alexander, started to walk off. The officer wrestled him to the ground and, in the process, spotted the handle of a machete under his clothing. After Alexander was handcuffed, the officer reached in and seized the weapon.
On appeal, Alexander contended that the officer did not have reasonable suspicion to search him because, (1) only one of the five or six students in the group was alleged to have a gun (so there was only about a 20% chance that he was the one), and (2) there was no reason for the officer to believe that the student who made the allegation was reliable. But the court rejected the argument, pointing out that one of the circumstances that can be properly considered is the potential for violence if officers neglected to act.
Said the court, “Here, suspicion was focused on a group of five or six students. Given the potential danger to students and staff which would have resulted from inaction, a weapons search of the several accused students was reasonable.”
Similarly, in People v. Joseph G. 13 a high school vice-principal in Spring Valley, California received a phone call from a parent who said that her son had been attending a high school football game a few days earlier when saw another student, Joseph G., carrying a handgun. The next morning, the vice-principal and a campus security officer searched Joseph's locker and found a handgun in his backpack. In upholding the search, the court noted, “The fact the mother named a particular student, apparently identified herself, and was a citizen-informant are all factors which weigh in favor of investigating the truth of her accusation by the minimal intrusion on Joseph's privacy of opening his locker, particularly when weighed against the gravity of the danger posed by possession of a firearm or other weapon on campus.”
Furthermore, although the caller did not know where the gun was located, the court noted that the locker was a logical place to look for it because a student who carries a weapon to school will probably keep it there or on his person. Thus, the court ruled the vice-principal had sufficient grounds to believe that a gun was located in Joseph’s backpack.
As noted, a search is permitted even if its purpose was to investigate a violation of a school rule. For example, in New Jersey v. T.L.O.14 the United States Supreme Court ruled that a vice-principal’s search of a high school student’s purse for cigarettes was lawful because the student had been caught smoking in a lavatory in violation of school rules.
Detentions on school grounds
The requirements for detaining students on school grounds are even less demanding than those for searches. In fact, neither probable cause nor reasonable suspicion is required. Instead, the only requirement is that the detention must not have been conducted for some arbitrary or capricious reason, or for the purpose of harassment.15
The reason for such an undemanding requirement is that school officials must be able to address safety and misbehavior concerns on school grounds without undue delay. In addition, detentions of students on school grounds are relatively unintrusive because a student’s freedom of movement is necessarily restricted simply by virtue of being on school property. As the California Supreme Court observed:
While at school, a student may be stopped, told to remain in or leave a classroom, directed to go to a particular classroom, given an errand, sent to study hall, called to the office, or held after school. Unlike a citizen on the street, a minor student is subject to the ordering and direction of teachers and administrators.16
Consequently, a student may be detained for merely violating a school rule. For example, in People v. William V.17 a school resource officer at Hayward High School saw that a student named William “had a neatly folded red bandanna hanging from the back pocket of his pants.” This caught the officer’s attention because, as he testified, colored bandannas “commonly indicate gang affiliation” and are therefore not permitted on campus.
Furthermore, he explained that the manner in which the bandanna was folded and hanging from the pocket indicated to him that “something was about to happen or that William was getting ready for a confrontation.” The officer’s suspicions were heightened when, as William made eye contact with him, he “became nervous and started pacing,” and he began “trembling quite heavily, his entire body, especially his hands, his lips, his jaw.” At that point, the officer detained William, seized the bandanna, and pat searched him. In the course of the search, he found a knife.
William contended the detention was unlawful because the officer did not have reasonable suspicion to believe he was committing a crime. It didn’t matter, said the court, because “William’s violation of the school rule prohibiting bandannas on school grounds justified the initial detention.”18
As for detaining non-students, it appears that reasonable suspicion is still required. Even so, a non-student can be detained during school hours to confirm he has registered with the office as required by law.19 He may also be detained after school hours to confirm he has a legitimate reason for being there. For example, in People v. Joseph F.20 an assistant principal and resource officer at a middle school in Fairfield saw Joseph, a high school student, on campus at about 3 P.M. At the request of the assistant principal, the officer tried to detain him to determine whether he should be arrested for being an unregistered visitor on campus during school hours in violation of Penal Code § 627.2. But Joseph refused to stop, and the officer had to forcibly detain him. As the result, Joseph was arrested for battery on a peace officer engaged in the performance of his duties.
On appeal, Joseph argued that the officer was not acting in the performance of his duties because school hours had ended an hour earlier. The court responded that the detention of a high school student on a middle school campus is plainly lawful, if only to ascertain whether he has a legitimate reason for being there. Said the court, “[S]chool officials, or their designees, responsible for the security and safety of campuses should reasonably be permitted to detain an outsider for the limited purpose of determining such person’s identity and purpose regardless of ‘school hours.’”
Searches and detentions by police officers
There had been some uncertainty as to whether the less-restrictive rules pertaining to school searches and detentions apply when they were conducted by, or “at the behest of,” school resource officers or school district police officers, as opposed to unsworn school security officers.21 This uncertainty was, however, eliminated by the Court of Appeal in People v. William V.22 Said the court:
We see no reason to distinguish for this purpose between a non-law enforcement security officer and a police officer on assignment to a school as a resource officer.
The court added that requiring sworn officers to work under different—more demanding—rules than unsworn security officers would make no sense because it would “focus on the insignificant factor of who pays the officer’s salary, rather than on the officer’s function at the school and the special nature of the public school.”
Moreover, it is apparent that school resource officers and district police officers have been specially designated by school administrators to discharge certain duties that, while they could be undertaken by school administrators and teachers, are better suited for law enforcement officers with special training and experience.23 Thus, in discussing this issue, the Wisconsin Supreme Court observed:
Were we to conclude otherwise, our decision might serve to encourage teachers and school officials, who generally are untrained in proper pat down procedures or in neutralizing dangerous weapons, to conduct a search of a student suspected of carrying a dangerous weapon on school grounds without the assistance of a school liaison officer or other law enforcement official.24
It should be noted that school resource officers and district police officers, as well as school administrators, are “state actors” for purposes of determining the lawfulness of searches and seizures on public school grounds.25 Thus, as we discussed in the accompanying article “Searches by Civilians and Police Agents,” evidence and statements obtained by them in violation of the Fourth Amendment may be suppressed. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.07%3A_Searches_and_Detentions_on_School_Grounds.txt |
"Within the workplace context, this Court has recognized that employees may have a reasonable expectation of privacy against intrusions by police."
The United States Supreme Court(1)
Evidence of a crime will sometimes be located in a suspect's office, desk, file cabinet, computer, locker or other area at his or her workplace. In such cases, officers need to know how they can legally obtain the evidence. Do they need a warrant? Can the suspect's employer consent to the search? If so, what is the permissible scope of the search? Is the evidence admissible if the employer comes in on his own and turns it over to officers? These are some of the issues we will discuss in this article.
As we will explain, the rules regarding the admissibility of evidence obtained in the workplace depend mainly on who conducted the search. Was it a private employer, a governmental agency, or a law enforcement officer?
SEARCHES BY PRIVATE EMPLOYERS
In some cases an employer will discover evidence of a crime in an employee's desk, computer, or other location in the workplace. This may occur inadvertently or as the intentional result of a search. In any event, if the employer seizes the evidence and turns it over to police, the question arises: Is the evidence admissible in court?
The answer is as follows: The evidence will be admissible if, (1) the suspect's employer was a private company or individual, not a governmental agency; and (2) the employee who conducted the search did so on his own initiative with absolutely no police involvement. As the United States Supreme Court pointed out, the exclusionary rule Ais wholly inapplicable to a search or seizure, even an unreasonable one, effected by a private individual not acting as an agent of the Government or with the participation or knowledge of any governmental official."(2)
On the other hand, the evidence will be suppressed if an officer or other government employee requested, planned, or facilitated the search.(3)
Re-opening closed containers
If a private employer discovers evidence and turns it over to police, another legal issue may arise: If the evidence is in a container or is otherwise not in plain view when it was handed to officers, is a warrant required before officers may open the container?
The answer is that a warrant is required if the officers' act of opening the container permits them to see something that had not been observed previously by the employer. But a warrant is not required if the evidence, although not in plain view when it was received by officers, had been observed previously by the employer.(4)
For example, in United States v. Jacobsen(5) a cardboard box that was being shipped by Federal Express was accidentally torn by a forklift. When workers opened the package to examine its contents to prepare an insurance report they found a "tube" about ten inches long covered by duct tape. The workers cut open the tape and found four zip-lock plastic bags containing white powder. Suspecting drugs, the workers notified the DEA. Before the agents arrived, however, the FedEx workers put the plastic bags back in the tube and re-packaged the tube in the cardboard box. When agents arrived, they opened the box and the tube, then extracted some of the powder to conduct a field test which came back positive for cocaine.
The United States Supreme Court ruled the agents acted lawfully when they re-opened the tube and examined the powder because it had already been observed by FedEx workers. Said the Court, "[T]he removal of the plastic bags from the tube and the agent's visual inspection of their contents enabled the agent to learn nothing that had not previously been learned during the private search. It infringed no legitimate expectation of privacy and hence was not a >search' within the meaning of the Fourth Amendment."
The Court also ruled that agents did not need a warrant to conduct a field test of suspected drugs that are in their lawful possession because, "A chemical test that merely discloses whether or not a particular substance is cocaine does not compromise any legitimate interest in privacy."
Later, the California Court of Appeal ruled that if the field test confirms the substance was an illegal drug, a warrant would not be required to test the substance in a laboratory.(6) If, however, the field test was negative or inconclusive, laboratory testing is permitted only if officers obtain a warrant.(7)
SEARCHES BY GOVERNMENT EMPLOYERS
Special rules apply to searches that were made by government employers, such as a city, county, or state. This is because the Fourth Amendment governs searches made by public employees.(8) Consequently, evidence obtained as the result of a warrantless search will usually be suppressed, except in three situations:
1. No reasonable expectation of privacy: The employee did not have a reasonable expectation of privacy in the place or thing that was searched.
2. Reasonable suspicion: There was reasonable suspicion that evidence of work-related misconduct would be found in the place or thing that was searched; the place or thing that was searched was part of the "workplace"; and the search was reasonable in scope.
3. Consent: The employee consented to the search. No reasonable expectation of privacy
Evidence discovered by a government employee will not be suppressed if the suspect-employee did not have a reasonable expectation of privacy in the place or thing that was searched.(9) In determining whether a reasonable expectation of privacy existed in the workplace, the following principles apply:
Personal items: Employees will generally have a reasonable expectation of privacy in their personal effects in the workplace, such as purses, luggage and briefcases.(10) As the United States Supreme Court observed, "Not everything that passes through the confines of the business address can be considered part of the workplace context. An employee may bring closed luggage to the office prior to leaving on a trip, or a handbag or briefcase each workday. While whatever expectation of privacy the employee has in the existence and the outward appearance of the luggage is affected by its presence in the workplace, the employee's expectation of privacy in the contents of the luggage is not affected in the same way."(11) Thus, evidence obtained as the result of a public employer's warrantless search of such items will almost always be suppressed.
Property owned by the employer: An employee may also have a reasonable expectation of privacy as to some non-personal effects in the workplace, such as the employee's office, file cabinet, desk, and computer. There are, however, circumstances in which an employee could not reasonably expect privacy in such an area or thing, in which case the evidence would be admissible. Those circumstances are as follows:
Usual practices and procedures: An employee's expectation that items in the workplace would not be searched or observed may be unreasonable as the result of office practices and procedures. As the United States Supreme Court observed, "The operational realities of the workplace may make some employees' expectations of privacy unreasonable . . . Public employees' expectations of privacy in their offices, desks, and file cabinets . . . may be reduced by virtue of actual office practices and procedures. . . ."(12) For example, if workers or supervisors regularly enter the employee's office to retrieve files from a file cabinet, it would probably be unreasonable for the employee to expect that items in the file cabinet would remain private.(13)
Plain view: It would usually be unreasonable for an employee to expect privacy as to items out in the open in his office, especially if such items were observed by a supervisor or fellow employee. This is because, as the United States Supreme Court noted, "An office is seldom a private enclave free from entry by supervisors, other employees, and business and personal invitees. Instead, in many cases offices are continually entered by fellow employees and other visitors during the workday for conferences, consultations, and other work-related visits."(14)
Reasonable suspicion
A warrantless search of a public employee's workplace, including areas in which the employee had a reasonable expectation of privacy, is permitted if the following three requirements are met:
1. Reasonable suspicion: There was reasonable suspicion to believe the search would result in the discovery of evidence pertaining to work-related misconduct.(15) Under such circumstances, probable cause is not required because, as the United States Supreme Court explained, "Public employers have an interest in ensuring that their agencies operate in an effective and efficient manner, and the work of these agencies inevitably suffers from the inefficiency, incompetence, mismanagement, or other work-related malfeasance of its employees."(16) Consequently, the court ruled that "public employer intrusions on the constitutionally protected privacy interests of government employees for noninvestigatory, work-related purposes, as well as for investigations of work-related misconduct, should be judged by the standard of reasonableness."
2. Search of "workplace": A warrantless search based on reasonable suspicion is permitted only if the area or thing that was searched was located on the "workplace." Otherwise, a search warrant based on probable cause will be required. What does the term "workplace" mean in this context? According to the United States Supreme Court, the workplace "includes those areas and items that are related to work and are generally within the employer's control. At a hospital, for example, the hallways, cafeteria, offices, desks, and file cabinets, among other areas, are all part of the workplace."(17) On the other hand, an employee's personal effects, such as a purse, briefcase, or luggage, are not part of the workplace merely because they were on the premises when the search was conducted.(18)
3. Search was reasonable in scope: The search must not have been unduly intrusive.(19) Or, in the words of the U.S. Court of Appeals, "The search will be permissible in its scope when the measures adopted are reasonably related to the objectives of the search and not excessively intrusive in light of the nature of the misconduct."(20)
POLICE SEARCHES
Law enforcement officers may conduct a search of a suspect's workplace if the search was authorized by a warrant based on probable cause or the search was authorized by the terms of the employee's parole or probation.(21) As we will now discuss, a police search may also be based on two other legal theories:
1. The employee had no reasonable expectation that officers would not see or discover the evidence.
2. Officers obtained consent to search from the employee or the employer. No reasonable expectation of privacy
An employee cannot challenge the search of a place or thing in which he has no reasonable expectation that law enforcement officers would not see or discover the item seized.
Note, however, there is a significant difference between an employee's reasonable expectation that his employer would not invade a certain area versus the employee's reasonable expectation that the area would not be invaded by law enforcement officers.(22)Thus, while it might be unreasonable for an employee to expect that his employer would not look through his desk or files, it might be entirely reasonable for the employee to expect that such things would not be searched by law enforcement officers without a warrant.
Employee consents to search
The suspect may consent to a police search of those places and things in the workplace over which he has joint access or control.(23) The suspect may not, however, authorize a search of any other places or things in the workplace. Like any consent search, the following requirements must be met:
1. Express or implied consent: The employee expressly or impliedly consented to the search.(24)
2. Voluntary consent: The consent was voluntary, not the result of coercion.(25)
3. Search within scope of consent: Officers searched only those places and things they reasonably believed the employee authorized them to search.(26)
Employer consents to search
An employer may voluntarily give officers consent to search places and things in the workplace over which the employer has joint access or control for most purposes.(27) Areas and things over which such access and control usually exist include common areas that are generally used by, or accessible to, some or all employees. This would include conference rooms, file rooms, libraries, kitchens, and rest rooms.(28)
It would also include places and things that are used primarily by the employee if the employer, as a matter of actual practice, retained and exercised the right to access or control the place or thing.(29) In other words, joint access or control may exist when the employer has sufficient mutual use of the property for most purposes so that it reasonably appears the employer had the authority to permit the search in his own right.(30)
Note that an employer does not have "joint access or control" merely because he owns or is able to access the area or thing that was searched.(31) Nor does common authority exist merely because the employer has a key or master key that allows him access.(32)
Instead, what counts is whether the employee had exclusive access or control, or whether the employer regularly or at least occasionally used or accessed the place or thing so that it can be fairly said that the employee lacked exclusive control. For example, an employer will probably not have joint access or control over a desk or file cabinet in the employee's office which is used exclusively by the employee.(33)
In some cases, officers have obtained consent to search from an employer who they believed could consent to the search, but they later learn that the employer did not, in fact, have joint access or control over the place or thing that was searched. Does this invalidate the search? It depends on whether the employer was a private employer or government agency.
Private employers
If the employer was a private individual or company, a consent search will be upheld if the officers reasonably believed the employer had joint access or control for most purposes (also known as "common authority") over the place or thing that was searched.(34) In other words, the issue here is not whether the employer actually had such authority but whether the officers reasonably believed he did.(35)
Governmental agencies
Because governmental agencies are subject to Fourth Amendment restraints, consent from a public employer will be valid only if the public employer did, in fact, have joint access and control over the area or thing searched.(36) In other words, an officer's reasonable but mistaken belief that the employer could consent to the search would be insufficient. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.08%3A_Workplace_Searches.txt |
PETITIONER RESPONDENT
Maryland Jerome Edward Buie
LOCATION
Buie Residence
DOCKET NO. DECIDED BY
88-1369 Rehnquist Court
LOWER COURT
Maryland Court of Appeals
CITATION
494 US 325 (1990)
ARGUED
Dec 4, 1989
Decided
Feb 28, 1990
Granted
June 5, 1989
ADVOCATES
John L. Kopolow on behalf of the Respondent
Lawrence S. Robbins on behalf of the United States as amicus curiae, supporting the Petitioner
Facts of the case
On February 3, 1986, two men robbed a Godfather’s Pizza in Prince George’s County, Maryland. One of the men was wearing a red running suit. Later that day, the police obtained warrants for the arrest of Jerome Edward Buie and Lloyd Allen and put Buie’s house under surveillance. On February 5, the police arrested Buie in his house. Police found him hiding in the basement. Once Buie emerged and was handcuffed, an officer went down to determine if there was anyone else hiding. While in the basement, the officer saw a red running suit in plain view and seized it as evidence. The trial court denied Buie’s motion to suppress the running suit evidence, and he was convicted. The Court of Special Appeals of Maryland affirmed the trial court’s denial of the motion. The Court of Appeals of Maryland reversed.
Question
Does the Fourth Amendment prevent police officers from making a “protective sweep” at the site of an in-home arrest if they do not believe themselves or others to be in immediate danger?
FOR AGAINST
Stevens
Kennedy
Scalia
Blackmun
O’Conner
Rehnquist
White
Marshall
Brennan
Conclusion
7–2 Decision for Maryland Majority Opinion by Byron R. White
No. Justice Byron R. White delivered the opinion of the 7-2 majority.
The Court held that the potential risk to police officers of another person on the arrest site must be weighed against the invasion of privacy. Because the arrest in this case happened in the suspect’s home, the officer was put at even greater risk because of the possibility of an ambush. This risk justified the protective sweep. The Court also held that a protective sweep was meant to be a cursory one, and not an in-depth search of the premises that would require a specific warrant.
In his concurring opinion, Justice John Paul Stevens wrote that the state has the burden to prove that the search was protective in nature. He argued that the state must show that the officers had a “reasonable basis” for believing that there was a risk to themselves. In his concurring opinion, Justice Anthony M. Kennedy wrote that he disagreed with Justice John Paul Stevens. He argued that the protective sweep was an element of police safety procedure, so the state did not have as high of a burden as Justice Stevens’ concurrence implied. Justice William J. Brennan, Jr. wrote a dissent where he argued that the protective sweep represented the type of intrusive unwarranted search that the Fourth Amendment was created to prevent.
6.10: Chimel v. California
PETITIONER RESPONDENT
Chimel California
LOCATION
Chimel’s Home
DOCKET NO. DECIDED BY
770 Burger Court
CITATION
395 US 752 (1969)
ARGUED
Mar 27, 1969
DECIDED
Jun 23, 1969
Facts of the case
Local police officers went to Chimel's home with a warrant authorizing his arrest for burglary. Upon serving him with the arrest warrant, the officers conducted a comprehensive search of Chimel's residence. The search uncovered a number of items that were later used to convict Chimel. State courts upheld the conviction.
Question
Was the warrantless search of Chimel's home constitutionally justified under the Fourth Amendment as "incident to that arrest?"
FOR AGAINST
Douglas
Marshall
Warren
Stewart
Harlan
Brennan
White
Black
Conclusion
6–2 Decision for Chimel Majority Opinion by Potter Stewart
In a 7-to-2 decision, the Court held that the search of Chimel's house was unreasonable under the Fourth and Fourteenth Amendments. The Court reasoned that searches "incident to arrest" are limited to the area within the immediate control of the suspect. While police could reasonably search and seize evidence on or around the arrestee's person, they were prohibited from rummaging through the entire house without a search warrant. The Court emphasized the importance of warrants and probable cause as necessary bulwarks against government abuse. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/06%3A_Search_and_Siezure_of_Things/6.09%3A_Maryland_v._Buie.txt |
PETITIONER RESPONDENT
Freemont Weeks United States
DOCKET NO. DECIDED BY
461 White Court
LOWER COURT
Federal District Court
CITATION
232 US 383 (1914)
ARGUED
Dec 1-2, 1914
DECIDED
Feb 24, 1914
ADVOCATES
Martin J. O'Donnell for Weeks
John W . Davis Solicitor General, Department of Justice, for the United States
Winfred T. Denis on Assistant Attorney General, Department of Justice, for the United States
Facts of the case
Police entered the home of Fremont Weeks and seized papers which were used to convict him of transporting lottery tickets through the mail. This was done without a search warrant. Weeks took action against the police and petitioned for the return of his private possessions.
Question
Did the search and seizure of Weeks' home violate the Fourth Amendment?
Conclusion
Decision for Weeks by William R. Day
UNANIMOUS
Day
White
McKenna
Holmes
Lurton
Hughes
Van Devanter
Lamar
Pitney
The Fourth Amendment prohibition against unlawful searches and seizures applies to Weeks and the evidence thus seized must be excluded from prosecuting him. In a unanimous decision, the Court held that the seizure of items from Weeks' residence directly violated his constitutional rights. The Court also held that the government's refusal to return Weeks' possessions violated the Fourth Amendment. To allow private documents to be seized and then held as evidence against citizens would have meant that the protection of the Fourth Amendment declaring the right to be secure against such searches and seizures would be of no value whatsoever. This was the first application of what eventually became known as the "exclusionary rule."
7.2: Wong Sun v. United States
PETITIONER RESPONDENT
Wong Sun and James Wah Toy United States
LOCATION
James Wah Toy’s Laundry
DOCKET NO. DECIDED BY
36 Warren Court
LOWER COURT
United States Court of Appeals for the Ninth Circuit
CITATION
371 US 471 (1963)
ARGUED
Mar 28, 1962 / Apr 01, 1962
REARGUED
Oct 8, 1962
DECIDED
Jan 14, 1963
GRANTED
Oct 9, 1961
ADVOCATES
Edward Bennett Williams acting under appointment by the Court, for the petitioners
Archibald Cox Solicitor General, Department of Justice, for the United States
Facts of the case
Police arrested Hom Way for possession of heroin. While under arrest, Way told police that a man named “Blackie Toy” once sold him an ounce of heroin at his laundry on Leavenworth St. Later that day, police found a laundry run by James Wah Toy. Nothing on the record identified Toy as “Blackie Toy”, but police arrested him anyway. Police then went to Toy’s house where they arrested Johnny Yee and found several tubes containing less than one ounce of heroin. Police also arrested Wong Sun. Police interrogated the men and wrote statements in English for them to sign. Both men refused, citing errors in the statements. At trial in U.S. District Court, Toy and Sun were convicted on federal narcotics charges. On appeal, the U.S. Court of Appeals for the Ninth Circuit affirmed.
Question
1. Were the petitioners' arrests lawful?
2. Were the petitioners' unsigned statements admissible as evidence?
Conclusion
5–4 DECISION FOR WONG SUN MAJORITY OPINION BY WILLIAM J. BRENNAN, JR.
FOR AGAINST
Douglas
Black
Goldberg
Warren
Brennan
White
Clark
Harlan
Stewart
Prejudicial error at trial may have considered each petitioner's statement as corroboration of the other petitioner's guilt No, No. In a 5-4 decision, Justice William J. Brennan wrote the majority opinion reversing the lower court and remanding for a new trial. The Supreme Court held that the police did not have probable cause to justify the arrests. With regard to Toy, the court should exclude all evidence found during the search because they are the “fruits” of an unlawful search. The unsigned statement was not corroborated, so it gave no basis for conviction. Sun’s unsigned confession and evidence against him were admissible. Justice Tom C. Clark wrote a dissent, stating that the arrests were lawful and there was no reason to grant Sun a new trial. Justices James M. Harlan, Potter Stewart, and Byron R. White joined in the dissent. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/07%3A_The_Exclusionary_Rule/7.1%3A_Weeks_v._United_States.txt |
“It is well established that under certain circumstances the police may seize evidence in plain view without a warrant.” 1
here is general agreement that the plain view rule is fairly simple to understand and apply. Even the words “plain view” seem to to saying,
“If it’s visible, it’s seizable!” Of course, it is not that simple, but it’s not very complicated either. Specifically, evidence is deemed in plain view—and can therefore be seized without a warrant—if the following circumstances existed:
1. Lawful vantage point: The officers’ initial viewing of the evidence must have been “lawful.”
2. Probable cause: Before seizing the evidence, officers must have had probable cause to believe it was, in fact, evidence of a crime
3. Lawful access: Officers must have had a legal right to enter the place in which the evidence was located.
If these circumstances exist, the officers’ act of observing the evidence does not constitute a “search” because no one can reasonably expect privacy in something that is so readily exposed; and their act of seizing the evidence is lawful because the plain view rule constitutes an exception to the warrant requirement.2 As the United States Supreme Court explained, “The seizure of property in plain view involves no invasion of privacy and is presumptively reasonable.”3
Lawful Vantage Point
The requirement that the officers’ initial observation of the evidence must have been “lawful” is satisfied if the officers did not violate the suspect’s Fourth Amendment rights by getting into the position from which they saw it.4 “The plain view doctrine,” said the Supreme Court, “is grounded on the proposition that once police are lawfully in a position to observe an item first-hand, its owner’s privacy interest in that item is lost.”5
Before we discuss the types of places from which an observation is apt to be legal, it should be noted an observation does not become an unlawful search merely because officers had to make some effort to see the evidence, so long as the effort was reasonably foreseeable. Thus, it is unimportant that officers could not initially see the evidence without using a common visual aid (such as a flashlight or binoculars),6 or without bending down or elevating themselves somewhat. Thus, the D.C. Circuit explained, “That a policeman may have to crane his neck, or bend over, or squat, does not render the [plain view] doctrine inapplicable, so long as what he saw would have been visible to any curious passerby.”7 Similarly, the Court of Appeal ruled that merely looking over the five-foot fence from a neighbor’s yard “disclosed no more than what was in plain view.”8
In contrast, the courts have ruled that officers “searched” a high-rise apartment when they could only see the evidence inside by using high-power binoculars from a hilltop about 250 yards away,9 or when officers “had to squeeze into a narrow area between the neighbor’s garage and defendant’s fence” and that area was almost blocked by foliage.10
OBSERVATION FROM PUBLIC PLACE
The most obvious example of a lawful vantage point is a place that is accessible to the general public.11 Thus, the Supreme Court pointed out that “the police may see what may be seen from a public vantage point where they have a right to be,”12 and that officers “cannot reasonably be expected to avert their eyes from evidence of criminal activity that could have been observed by any member of the public.”13
OBSERVATION DURING DETENTION OR ARREST
An observation that occurred in the course of a detention is lawful if officers had sufficient grounds for the detention or arrest and it was reasonable in its scope and intensity.14 For example, in People v. Sandoval 15 the Court of Appeal ruled that an officer, having made a lawful car stop, lawfully observed drugs and paraphernalia in the passenger compartment because “the officer clearly had a right to be in the position to have that view.”
OBSERVATION DURING PAT SEARCH
In a variation of the plain view rule (i.e., the “plain feel” rule), officers who feel evidence while conducting a pat search are deemed to be in a lawful vantage point if they had grounds for the search.16 In such cases, said the Third Circuit, the “proper question” is whether the officer detected the evidence “in a manner consistent with a routine frisk.”17 Or, in the words of the Supreme Court, a lawful pat search must “be confined in scope to an intrusion reasonably designed to discover guns, knives, clubs, or other hidden instruments for the assault of the police officer.”18
OBSERVATION WHILE EXECUTING A SEARCH WARRANT
Officers who are executing search warrants often find evidence that was not listed in the warrant. When this happens, the discovery will be deemed lawful under the plain view rule if they found the evidence while looking in places or things in which any of the listed evidence might have been found. For example, in Skelton v. Superior Court 19 officers in La Palma were searching for a wedding ring and carving set which were taken in a burglary. While searching for these items, they also found some watches and rings that matched the descriptions of items taken in related burglaries. On appeal, the California Supreme Court ruled the unlisted evidence was lawfully discovered because “the warrant mandated a search for and seizure of several small and easily secreted items” and therefore “the officers had the authority to conduct an intensive search of the entire house.”
Similarly, in U.S. v. Smith,20 officers in Tampa obtained a warrant to search the home of Smith’s mother for drugs and indicia. In the course of the search, they opened Smith’s lockbox and found child pornography. In ruling that the pornography was discovered lawfully, the court said, “It was through the lawful execution of the warrant that the officers came across the photographs at issue here.”
In contrast, in People v. Albritton 21 narcotics officers in Bakersfield obtained a warrant to search the defendant’s home for drugs and indicia. A detective assigned to the auto theft detail learned about the warrant and decided to “go along for the ride” because the defendant was also a suspected car thief. When the officers arrived, the detective “immediately separated himself from the others and went to the garage” where he checked the VIN numbers on several cars and learned that four were stolen. On appeal, prosecutors argued that the detective’s initial viewing of the VIN numbers was lawful, and therefore the plain view rule applied. But the court disagreed, ruling the detective’s observation of the VIN numbers was unlawful because none of the evidence listed in the search warrant could reasonably have been found in the areas in which the VIN numbers were located.
OBSERVATION DURING WARRANTLESS ENTRY
In a similar vein, officers may seize evidence inside a residence if (1) they were lawfully on the premises (e.g., exigent circumstances, consentual entry, execution of an arrest warrant), and (2) they discovered the evidence while they were carrying out their lawful duties. For example, if the officers’ entry into a living room was consensual (e.g., a knock and talk), and if they saw drugs in the room, their observation would be deemed lawful because they had been invited into that room. But if they saw the evidence by opening a container in the living room or while wandering into another room, the observations would be unlawful.
A good example of such an unlawful observation is found in Arizona v. Hicks 22 in which officers had entered Hicks’ apartment without a warrant because someone in his apartment had fired a shot through the floor, injuring an occupant in the apartment below. While looking around, one of the officers noticed an expensive audio system which he thought might have been stolen because the apartment was otherwise “squalid.” The officer then confirmed his suspicion by picking up a component, writing down the serial number, and running it through a police database. Although the U.S. Supreme Court ruled that the entry into the apartment was lawful, it ruled that the serial number was not in plain view because the officer could not have seen it without doing something (picking up the component) that went beyond the objective of the entry, which was to apprehend the shooter and look for any other injured people.
OBSERVATION DURING ENTRY INTO YARDS
As with warrantless entries into residences, warrantless entries into a suspect’s front, back, or side yards may fall within an exception to the warrant requirement (e.g., exigent circumstances, consent), in which case their observations would be lawful. In the absence of a warrant, officers may still walk to the front door via normal access routes, then knock or otherwise announce their presence. But if no one answers the door within a reasonable time, any observations they make may be illegal if they loitered on the property or explored the grounds. As the Supreme Court explained, officers are impliedly authorized “to approach the home by the front path, knock promptly, wait briefly to be received, and then (absent invitation to linger longer) leave.”23
For example, in People v. Edelbacher 24 the defendant shot and killed his estranged wife in Fresno County, then drove to his home in Madera County. A sheriff’s deputy who was investigating the murder drove to Madera and, while standing on Edelbacher’s driveway, saw shoe prints that looked just like the shoe prints that had been found at the murder scene. Consequently, officers took photos of the shoe prints and prosecutors used them against Edelbacher at his trial. On appeal, he argued that the discovery was unlawful because the deputy had been standing on his private property. It didn’t matter, said the California Supreme Court, because the prints “were apparently visible on the normal route used by visitors approaching the front doors of the residences and there is no indication of solid fencing or visible efforts to establish a zone of privacy.”
OBSERVATION FROM ADJACENT PROPERTY
An observation of evidence in a suspect’s yard or other private property is not unlawful if it was made from a neighbor’s property, even if the officers were technically trespassing.25 This is because it was the neighbor who was intruded upon—not the suspect. As the Court of Appeal observed, “[A] search does not violate the Fourth Amendment simply because police officers trespassed onto a neighbor’s property when making their observations.”26
OBSERVATION DURING COMPUTER SEARCH
Officers who are executing a warrant to search a computer will often discover unlisted data or evidence of some other crime. When this happens the discovery will be deemed lawful under the plain view rule if the file in which the evidence was found could have contained any of the data or graphics listed in the warrant. In most cases, that means every file must be read because, as the Ninth Circuit pointed out in U.S. v. Comprehensive Drug Testing, Inc., unless officers read every file they would have “no way of knowing which or how many illicit files there might be or where they might be stored.”27
Probable Cause
The second requirement for a plain view seizure is that the officers—at or before the moment they seized the evidence—must have had probable cause to believe the item was, in fact, evidence of a crime.28 And like the other forms of proof, probable cause to seize an item in plain view may be based on direct or circumstantial proof. Examples of direct proof would include an officer’s observation of a weapon that is illegal to possess,29 a weapon used in a crime,30 readily-identifiable drugs or drug paraphernalia,31 readily-identifiable child pornography,32 or property that had been reported stolen.33
As we will now discuss, circumstantial proof typically consists of an officer’s observation of something that, based on his training and experience, appears to be seizable evidence.
INSTRUMENTALITIES OF A CRIME
Probable cause is often based on an officer’s knowledge of a link between the item and a certain crime or a type of crime. The following are examples of such a link:
• A man suspected of having just robbed a bank had a large amount of cash protruding from his wallet.34
• A suspect in an armed robbery or shooting possessed firearms, ammunition, shell casings;35 clothing that matched those of the perpetrator;36 a mask (the perpetrator wore one);37 a handcuff key (the victim had been handcuffed).38
• A murder suspect possessed bailing wire (bailing wire had been used to bind the victims).39
• A murder suspect possessed “cut-off panty hose” (the officer knew that the murderers had worn masks and that cut-off panty hose are used as masks).40
• A man who had solicited the murder of his estranged wife possessed a hand-drawn diagram of his wife’s home and lighting system.41
• A burglary suspect possessed pillow cases filled with “large, bulky” items 42 or burglary tools.43
• A suspected drug dealer possessed “a bundle of small, plastic baggies”;44 a “big stack or wad of bills”;45 firearms.46
STOLEN PROPERTY
Circumstantial evidence that property was stolen may consist of the condition of the property, such as obliterated serial numbers, clipped wires, and pry marks. For example, in People v. Gorak 47 the court ruled that officers had probable cause to seize an air compressor in plain view in the back seat of the defendant’s car mainly because “the electrical lines and air lines appeared to have been broken off” and water was leaking out of a broken line. Similarly, in People v. Stokes 48 two Hayward police officers in an unmarked car were driving through a mobile home park that was occupied mainly by senior citizens. As they turned a corner, they saw Stokes standing in the middle of the street, holding a video recorder. The officers recognized Stokes as a local burglar, they noticed that he kept looking around and appeared to be nervous, that he was carrying a screwdriver, and that several homes in the park had recently been burglarized. Although the officers had no direct evidence that the recorder had been stolen, the court ruled that the circumstantial evidence was quite sufficient.
Other circumstantial evidence that may suffice include the presence of store merchandise tags or anti-shoplifting devices that are usually removed when retail goods are sold; or the presence of an inordinate amount of property, especially the type of property that is frequently stolen, such as TVs, cell phones, tablets, firearms, and jewelry.49
POSSESSION OF DRUGS, PARAPHERNALIA
Officers frequently develop probable cause to seize a container in the possession of a drug user or trafficker based entirely on circumstantial evidence that it contained drugs, paraphernalia, or evidence of sales.50 As the court observed in People v. Holt, “Courts have recognized certain containers as distinctive drug carrying devices which may be seized upon observation: heroin balloons, paper bindles and marijuana smelling brick-shaped packages.”51
Probable cause may also be based on how the object felt; i.e., “plain feel.”52 For example, in People v. Lee 53 an Oakland police officer was pat searching a suspected drug dealer when he felt “a clump of small resilient objects” which he believed (correctly) were heroin-filled balloons. In ruling that the officer’s seizure of the balloons was lawful under the “plain feel” rule, the court noted that he “recognized the feel of such balloons from at least 100 other occasions on which he had pat-searched people and felt what were later determined to be heroin-filled balloons. As he described it, the feel is unmistakable.”
Lawful Access
Finally, even if officers could see the evidence and had probable cause to believe it was seizable, they may not enter the suspect’s home or other place in which he had a reasonable expectation of privacy unless they had a legal right to enter; e.g., a vehicle in which the evidence was located.54 Thus, in discussing the plain view rule, the Supreme Court explained that “not only must the officer be lawfully located in a place from which the object can be plainly seen, but he or she must also have a lawful right of access to the object itself.”55 Or, as Justice Grodin observed in People v. Superior Court (Spielman), “Seeing something in plain view does not, of course, dispose, ipso facto, of the problem of crossing constitutionally protected thresholds. Those who thoughtlessly overapply the plain view doctrine to every situation where there is a visual open view have not yet learned the simple lesson long since mastered by old hands at the burlesque houses, ‘You can’t touch everything you can see.’”56 Note that officers will always have lawful access to evidence located in a public place or a vehicle located in a public place.57 In addition, they may enter a residence and seize evidence observed from the outside if they were aware that a resident was subject to a parole or probation search or if they reasonably believed the evidence would be destroyed if they delayed seizing it.
For example, in People v. Ortiz 58 an officer happened to be walking by the open door of a hotel room when he saw a woman inside, and she was “counting out tinfoil bindles and placing them on a table.” Having probable cause to believe the bindles contained heroin, the officer went inside, seized the bindles, and arrested the woman and the other occupants. In ruling that the officer had lawful access to the evidence, the court pointed out that, because he was initially only three to six feet away from the woman, he reasonably believed that she had seen him and it is “common knowledge that those who possess drugs often attempt to destroy the evidence when they are observed by law enforcement officers.” Consequently, the court ruled that the officer had a legal right to enter because “it was reasonable for [him] to believe the contraband he saw in front of defendant and the woman was in imminent danger of being destroyed.
8.2: Arizona v. Hicks
PETITIONER RESPONDENT
Arizona Hicks
LOCATION
Apartment of Hicks
DOCKET NO. DECIDED BY
85-1027 Rehnquist Court
LOWER COURT
Sate Appellate Court
CITATION
480 US 321 (1987)
ARGUED
Dec 8, 1986
DECIDED
Mar 3, 1987
ADVOCATES
John W. Rood, III By appointment of the Court, argued the cause for the respondent
Linda A. Akers Argued the cause for the petitioner
John William Rood for respondent
Facts of the case
A bullet was fired through the floor of Hicks's apartment which injured a man in the apartment below. To investigate the shooting, police officers entered Hicks's apartment and found three weapons along with a stocking mask. During the search, which was done without a warrant, an officer noticed some expensive stereo equipment which he suspected had been stolen. The officer moved some of the components, recorded their serial numbers, and seized them upon learning from police headquarters that his suspicions were correct.
Question
Was the search of the stereo equipment (a search beyond the exigencies of the original entry) reasonable under the Fourth and Fourteenth Amendments?
Conclusion
6–3 Decision
Majority Opinion by Antonin Scalia
FOR AGAINST
Blackmun
White
Scalia
Stevens
Brennan
Marshall
Powell
Rehnquist
O’Connor
No. The Court found, that the search and seizure of the stereo equipment violated the Fourth and Fourteenth Amendments. Citing the Court's holding in Coolidge v. New Hampshire (1971), Justice Scalia upheld the "plain view" doctrine which allows police officers under some circumstances to seize evidence in plain view without a warrant. However, critical to this doctrine, argued Scalia, is the requirement that warrantless seizures which rely on no "special operational necessities" be done with probable cause. Since the officer who seized the stereo equipment had only a "reasonable suspicion" and not a "probable cause" to believe that the equipment was stolen, the officer's actions were not reconcilable with the Constitution. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/08%3A_The_Plain_View_Doctrine/8.1%3A_Plain_View_Doctrine.txt |
“The Fourth Amendment prohibits unreasonable searches and seizures, not trespasses.” 1
Law enforcement officers regularly walk and drive onto private property. It happens so often it’s hardly noteworthy. Although some might call it “trespassing,” to most people it’s insignificant, a nonevent.
Sometimes, however, it turns into a big deal—like when officers see something that results in a search or an arrest. Maybe they’ll trip over a marijuana plant, or happen to see the residents sitting around the kitchen table packaging heroin or cleaning their rocket launchers. In any event, evidence discovered as the result of an entry onto private property will be suppressed if the officers’ entry constituted an illegal “search.”
It might seem crazy to think of walking or driving onto private property as a “search.” But it is—at least under certain circumstances. What are those circumstances? And when is such a search lawful? These are the questions we will answer in this article.
Before we start, it should be noted that there are two kinds of trespassing: criminal and “technical.” The criminal variety is trespassing that is unlawful, such as occupying real property, or refusing to leave after being requested to do so by the owner.2 This is not the type of trespassing that officers are likely to do. Even when they refuse an owner’s request to leave, their continued presence is hardly ever a criminal trespass because it’s usually justified under some exception to the warrant requirement.
On the other hand, officers routinely commit technical or “common law” trespassing, which is simply walking or driving onto private property without the owner’s permission.3 Although technical trespassing is not unlawful,4 it’s the type of trespassing that is most likely to constitute a “search.”
Finally, in this article the word “curtilage” in used in a few places. It’s a word from the common law which, for our purposes, simply means the private property immediately surrounding a home; e.g., the front, back, and side yards.5
WHEN TRESPASSING IS A “SEARCH”
A trespass by officers is a “search” if it permitted them to see or hear something the occupants reasonably believed would be private.6 As the U.S. Court of Appeals put it:
Whether a police officer has commenced a “search” turns not on his subjective intent to conduct a search and seizure, but rather whether he has in fact invaded an area which the defendant harbors a reasonable expectation of privacy.7
As we will now discuss, whether an expectation of privacy exists and is reasonable depends largely on two things: (1) the nature of the property officers entered; and (2) whether, or to what extent, the occupants took steps to prevent or discourage entry.
Front yards
The least private area surrounding most homes and other structures is almost always the front. This is because it is usually visible to the public and it’s where visitors, tradespeople, and others must walk to reach the front door. Consequently, in determining whether an officer’s entry into the front yard constituted a search, the courts focus mainly on the extent to which visitors and others might use it to contact the occupants.
ACCESS ROUTES
There can be no reasonable expectation that officers and others will not walk on walkways, pathways, porches, and other access routes to the front door.8
Accordingly, an officer’s presence on an access route is not a “search.”9 As the U.S. Court of Appeals put it, “[N]o Fourth Amendment search occurs when police officers who enter private property restrict their movements to those areas generally made accessible to visitors . . . .”10
In fact, the California Supreme Court has ruled that the occupants of a residence impliedly consent to entries on access routes. Said the court, “A sidewalk, pathway, common entrance or similar passageway offers an implied permission to the public to enter which necessarily negates any reasonable expectation of privacy in regard to observations made there.”11
The question arises: Can officers depart somewhat from a pathway without converting their departure into a search? And if so, how far? It appears that officers, like other visitors, may stray somewhat from a path provided their detour was neither substantial nor unreasonable.12
DRIVEWAYS
Driveways are sometimes used as pathways—sometimes the only pathway—to the front of a house. If so, for the reasons discussed above, an officer’s entry onto a driveway is not a search.
But even if the driveway was not a pathway to the front door, the occupants can seldom expect that officers and others will not walk on the driveway unless there were unusual circumstances that restricted such access.13 As the U.S. Court of Appeals pointed out:
Whether a driveway is protected from entry by police officers depends on the circumstances. The fact that a driveway is within the curtilage of a house is not determinative if its accessibility and visibility from a public highway rule out any reasonable expectation of privacy.”14
For example, the courts have ruled that officers did not need a warrant to walk onto a suspect’s driveway to install a tracking device under his car or to record his car’s license number.15 Another example is found in U.S. v. Ventling 16 where a forest service agent was investigating the construction of an illegal roadblock on a government road. The agent noticed tire tracks leading from the roadblock to the driveway of Ventling’s house. So he followed the tracks down the driveway where the took photos of them. The photos were later used in Ventling’s trial on a charge of blocking a Forest Service road. In ruling that the agent was not conducting a “search” when he drove down the driveway, the court said:
[A] driveway and portion of the yard immediately adjacent to the front door of the residence can hardly be considered out of public view. The extension of Ventling’s expectations of privacy to the driveway and that portion of the yard in front of the house do not, under these circumstances, appear reasonable.
Side yards
Like the driveway, the unfenced side areas of a home are usually visible to the public and are readily accessible. Still, unless there is a normal access route or walkway along the side of the house, the courts view unfenced side yards as somewhat more private than the front. And it becomes more private as the entry becomes more unusual or unexpected; e.g., entry late at night, officers had to climb over bushes to get into yard, officers traversed almost the entire side of the house. For example, in People v. Camacho 17 officers in Ventura County were dispatched to investigate a complaint of a “loud party disturbance” at Camacho’s home. The call came in at about 11 P.M. When the officers arrived they heard no loud noise and saw no sign of a party. Still, they decided to investigate. But instead of knocking on Camacho’s front door, one of the officers walked into the side yard which the court described as follows:
“[A]n open area covered in grass. No fence, gate or shrubbery suggested entrance was forbidden. Neither, however, did anything indicate the public was invited to enter; there was neither a path nor a walkway, nor was there an entrance to the house accessible from the side yard.
While in the side yard, the officer noticed a window that was open a few inches and was not covered by curtains. Looking through the window, he saw Camacho packaging cocaine. The officers then entered the house through the window and arrested him.
In ruling the officers’ entry into the side yard was an unlawful “search,” the court observed “Most persons, we believe, would be surprised, indeed startled, to look out their bedroom window at such an hour to find police officers standing in their yard looking back at them.” Similarly, in Lorenzana v. Superior Court 18 officers went to Lorenzana’s apartment at about 10 P.M. to investigate a tip that heroin was being sold there. Although there were no doors or pathways along the east side of the apartment, an officer walked there and, through a partially open window, was able to hear Lorenzana talking on the phone about a heroin sale he was about to make. This ultimately led to Lorenzana’s arrest.
The California Supreme Court ruled, however, the officer was conducting an illegal “search” when he heard the incriminating conversation. This was essentially because, (1) there were no pathways or doors at this side of the apartment, and (2) the area along the east side was not a common area for other apartment residents—it was solely for Lorenzana’s use.
Backyards
Privacy expectations in backyards (including fenced side yards) are almost always higher—usually much higher—than those in the front. There may be several reasons for this, such as, (1) most backyards are not readily visible to the public, (2) normal access routes seldom go through backyards, (3) backyards are usually surrounded by fences, and (4) the family activities that commonly occur in backyards more closely resemble the so-called “intimate” household activities that are afforded greater protection under the Fourth Amendment. As the court observed in People v. Winters,19 “A person who surrounds his backyard with a fence and limits entry with a gate, locked or unlocked, has shown a reasonable expectation of privacy.”
To the extent that one or more of these circumstances do not exist, however, privacy expectations may be reduced, maybe even eliminated. For example, if access to the house is normally made from both the front and back, an officer’s entry into the backyard would not constitute a search. As the court observed in U.S. v. Garcia,20 “If the front and back of a residence are readily accessible from a public place, like the driveway and parking area here, the Fourth Amendment is not implicated when officers go to the back door reasonably believing it is used as a principal entrance to the dwelling.”
Similarly, if the front door is inaccessible, and if officers have a legitimate reason for contacting an occupant, it may be reasonable for them to go to the back to find another door. This occurred in U.S. v. Daoust 21 where officers, having received a tip that Daoust might have some information about illegal drug activities, went to his house to speak with him. Upon arrival, they discovered that the stairs leading up to the front door were missing. And because the front door was five feet above the ground, the door was essentially “inaccessible.” So the officers walked into the unfenced backyard, looking for another door. While there, they saw a gun inside the house, which led to Daoust’s arrest for being a felon in possession of a firearm. In ruling the officers’ entry into the backyard was lawful, the court said:
A policeman may lawfully go to a person’s home to interview him. In doing so, he obviously can go to up the front door, and, it seems to us, if that door is inaccessible there is nothing unlawful or unreasonable about going to the back of the house to look for another door, all as part of a legitimate attempt to interview a person.
“Open fields”
There can be no reasonable expectation of privacy in a so-called “open field,” even if the property was obviously private. What is an “open field?” It is essentially any unoccupied and undeveloped private residential property that is outside the curtilage of a home, almost always in rural areas.22 It is also possible that unoccupied or undeveloped commercial property may constitute an “open field.”23
If property is deemed an “open field,” any evidence observed by officers while they are walking or driving on it cannot be suppressed.24 As the Court of Appeal observed, “A warrantless observation made by law enforcement from an open field enjoys the same constitutional protection as one made from a public place.”25 This is true even if the area is surrounded by a fences and NO TRESPASSING signs.26 For example, in United States v. Dunn 27 DEA agents entered a 198-acre “open field” that was “completely encircled by a perimeter fence” and “several interior fences, constructed mainly of posts and multiple strands of barbed wire.” In order to get close to two barns on the land, the agents had to climb over two barbed-wire fences and a wooden fence. As they approached one of the barns, they observed a PCP laboratory. Based on this observation, they obtained a warrant to search the barn.
In ruling the agents’ presence on the property did not constitute a “search,” the U.S. Supreme Court noted that it has “expressly rejected the argument that the erection of fences on an open field—at least of the variety involved in those cases and in the present case—creates a constitutionally protected privacy interest.” Thus, said the Court:
It follows that no constitutional violation occurred here when the officers crossed over respondent’s ranch-style perimeter fence, and over several similarly constructed interior fences, prior to stopping at the locked front gate of the barn.
Adjoining property
Private property adjacent to the suspect’s property is, by its very nature, not within the curtilage of the suspect’s house. It is, therefore, essentially an “open field” as to searches on the suspect’s property. For example, if the suspect’s neighbor permitted officers to use his property to watch the suspect’s activities, the officers would be, as far as the law is concerned, in an “open field” because it is outside the curtilage of the suspect’s house.28
Even if officers entered the neighbor’s property without the neighbor’s consent, the suspect would not have standing to challenge the legality of the entry. As the court observed in People v. Claeys,“[D]efendant’s Fourth Amendment rights stopped at his backyard fence because the [marijuana] plants were readily visible from his neighbor’s property and he had no reasonable expectation of privacy in what could be seen from there.”29
Multiple-occupant buildings
In multiple-occupant buildings, such as apartments and hotels, the occupants do not have a reasonable expectation of privacy in areas that are for the use of the tenants in general such as hallways, walkways, recreation facilities, parking lots, and enclosed garages.30 Consequently, an officer’s act of entering such a common area is not a “search.” As the court noted in People v. Seals:
[P]olice officers in performance of their duty may, without doing violence to the Constitution, enter upon the common hallway of an apartment building without warrant or express permission to do so.31
Note that an entry into such a common area is not a search even if officers entered through a locked door.32
Officers may also walk on areas outside the structure that are accessible to the tenants. For example, in U.S. v. Fields 33 narcotics officers in New Haven, Connecticut received reliable information that Fields was presently bagging crack cocaine in the rear of a certain apartment, and that his activities were visible through an open window. They arrived at the apartment at 8:25 P.M.; it was dark. Because the windows out front were covered, the officers walked into the “fenced-in side yard.” There they saw Fields bagging crack cocaine. On appeal, the court ruled that Fields could not reasonably expect that people would not be in his side yard because the area was readily accessible to the other residents of the building. Said the court, “[D]efendants here could have no such legitimate [privacy] expectations because the building in which they conducted their operations contained other apartments whose tenants were entitled to use the side yard without giving notice or having the defendant’s permission.”
Businesses
A search does not result from an officer’s entering a parking lot, business, or other commercial establishment to which the public was expressly or impliedly given access.34 As the U.S. Supreme Court observed in Maryland v. Macon,35 “The officer’s action in entering the bookstore and examining the wares that were intentionally exposed to all who frequent the place of business did not infringe a legitimate expectation of privacy and hence did not constitute a search within the meaning of the Fourth Amendment.”
Signs and fences
The posting of NO TRESPASSING signs may be relevant in determining whether the occupants reasonably expected privacy. It is not, however, nearly as significant as erecting fences that are constructed to keep people out.
“NO TRESPASSING” SIGNS
NO TRESPASSING signs are like blaring car alarms: they’re so common, they’re usually ignored.36 This is especially true if the sign is posted in a place where people can be expected to walk or drive. For example, it is unlikely that signs posted on a pathway leading to a home or apartment building would ever create a reasonable expectation that people would not walk to the front door.37 Similarly, NO TRESPASSING signs around an “open field” would not create a reasonable expectation of privacy because open fields are simply not private places.38
On the other hand, NO TRESPASSING signs at the entry to a backyard would be a more significant circumstance because backyards—especially fenced backyards—are traditionally much more private than front yards.
FENCES
Whether a fence creates or helps establish a reasonable expectation of privacy depends largely on the nature of the fence and the normal privacy expectations of the area it surrounds.39 For example, a fence surrounding an apartment house or other multiple-occupant building will seldom establish a reasonable expectation of privacy because the fence is obviously not intended to prevent entry by the residents, their visitors, and tradespeople. Similarly, as noted earlier, a fence surrounding an “open field” will not create or even contribute to the owner’s privacy expectations.
On the other hand, a fence surrounding the backyard of a single-family residence is much more likely to demonstrate a reasonable expectation of privacy because backyards are fairly private to the extent they’re not readily visible to the public and are not places where normal access routes are ordinarily found. As the Court of Appeal observed, “A person who surrounds his backyard with a fence and limits entry with a gate, locked or unlocked, has shown a reasonable expectation of privacy.”40
The manner in which a fence or barrier is constructed may also be relevant in determining privacy expectations.41 A homeowner who surrounds his home with an electrified chain link fence topped with razor wire could make a good case that he reasonably expected privacy. On the other hand, a white picket fence or a chain hanging between two posts would not be viewed as a serious effort to prevent entry. For example, in U.S. v. Reyes 42 a probation officer went to Reyes’ house to investigate a report from the DEA that Reyes, a probationer, might be growing large quantities of marijuana. When no one answered the front door, the probation officer walked down a gravel driveway along the side of the house to see if Reyes was in the backyard. There was a “chain hanging from two posts across a portion of the driveway” but it “did not extend the full width of the driveway.” While walking along the driveway, the probation officer spotted marijuana plants on Reyes’ property.
In ruling that Reyes could not reasonably expect that visitors would not walk along his driveway, the trial court said, “Although there was a chain to prevent vehicles from entering the driveway, there were no signs forbidding pedestrian access. [Furthermore] the driveway was not secluded in any manner. The driveway led to the street and could be viewed in its entirety from the street.” Thus, the court ruled, “In these circumstances, there was nothing inappropriate, much less unconstitutional, about the probation officers’ entry onto the driveway . . . ”
Finally, although the absence of a “serious” fence might suggest that no reasonable expectation of privacy exists, the courts have rejected the idea that people must construct fences in order to claim privacy. As the California Supreme Court stated in People v. Camacho,43 “[W]e cannot accept the proposition that defendant forfeited the expectation his property would remain private simply because he did not erect an impregnable barrier to access.”
LEGAL TRESPASS-SEARCHES
Even if an officer’s entry onto private property is a “search,” it’s not an unlawful search unless the intrusiveness of the trespass outweighed the law enforcement interest in being on the property. Consequently, to determine whether a trespass-search is lawful, the courts balance the justification for the trespass against its intrusiveness.44 If the justification outweighs the intrusiveness, the search is lawful. Otherwise. it’s unlawful.
Justification
Because the intrusiveness of most technical trespasses falls somewhere between nonexistent and trivial, not much justification is ordinarily required. Even so, officers must be able to articulate some legitimate law enforcement interest for entering the property—as opposed to “simply snooping.”45 The following are commonly cited:
To INVESTIGATE: Officers reasonably believed the entry was necessary to investigate a crime or suspicious circumstance.46
TO DETAIN OR ARREST: Officers had legal grounds to detain or arrest a person on the property.47
TO INSPECT STOLEN PROPERTY OR CONTRABAND: Officers entered the property to inspect property that they reasonably believed was stolen.48
TO SPEAK WITH OCCUPANTS: Officers had a duty to attempt to speak with the occupants.49
For example, in People v. Camacho,50 discussed earlier, officers received a complaint of a “loud party disturbance” at Camacho’s home at about 11 P.M. When they arrived, however, they heard no loud noise and found no sign of a party. Nevertheless, they walked into the side yard where they happened to see Camacho in a bedroom bagging cocaine. The court ruled the officers’ technical trespass was not justified because there was no disturbance and, therefore, no need to take any action. Said the court:
Indeed, had the officers on their arrival at defendant’s house heard a raucous party, confirming the anonymous complaint that brought them there in the first place, and had they then banged on the front door to no avail, their entry into the side yard in an attempt to seek the source of the noise would likely have been justified. [But here] the officers arrived at defendant’s home late in the evening and heard no such noise. Without bothering to knock on defendant’s front door, they proceeded directly into his darkened side yard.
Another example—this one demonstrating sufficient justification—is found in In re Gregory S.51 which involved a “malicious mischief” call at about 1:45 P.M. The Contra Costa County sheriff’s deputy who was dispatched to the call saw the suspect standing in the front yard of his home. But when the deputy stopped to talk with him, the suspect started to walk around the side of his house. The deputy called out twice, “Hey you. Come here,” but the suspect kept walking. As the officer was walking down the driveway toward the suspect, the suspect told him to get off his property. The deputy told the suspect that he was investigating a complaint by a neighbor and that he had a legal right to be there. The suspect then started to leave and a struggle ensued. The suspect was charged with interfering with an officer in the performance of his duties.52
In ruling the deputy had a right to be on the suspect’s property, the court said: Appellant argues that privacy was invoked when he ordered the officer off the property. But the officer had a right and commensurate duty to deal with the problem at hand. He did not enter the property arbitrarily. Appellant had ignored the officer’s earlier order to come to the street. If, despite the lack of indicia of privacy, the entry be deemed an intrusion, the entry and detention were authorized by the public concern to maintain peace in the neighborhood.
Keep in mind that if the trespass is more than minimally intrusive, the courts will require more justification.
Intrusiveness
Assuming that officers are able to articulate some justification for entering the property, the issue becomes whether that justification outweighed the intrusiveness of the officers’ entry. As a practical matter, most technical trespassing by officers involves nothing more than walking or driving onto private property which is seldom considered a significant intrusion. Sometimes, however, there are circumstances that increase the intrusiveness of the trespass, requiring additional justification. The following are circumstances that might be relevant:
TIME OF NIGHT: Privacy expectations may be affected by the time of day or night in which the entry occurred. Although there is little law on this subject, the court in People v. Camacho 53 cited the “lateness of the hour” (11 P.M.) as a circumstance indicating the defendant reasonably expected that officers and other people would not be walking along the side of his home.
LOOKING THROUGH WINDOWS: An entry may be deemed more intrusive if it enabled officers to see through a window that would otherwise not have afforded a view inside.54
CLIMBING LEDGE OR FIRE ESCAPE: An officer’s act of looking through the window of a home from a ledge, trellis, or fire escape may be deemed more intrusive because most people do not expect intruders on such places.55 However, an expectation of privacy would likely be unreasonable if the fire escape or ledge was routinely used by others.56
LENGTH OF TRESPASS: Sometimes cited but only marginally important; most are very brief.57
OFFICERS ORDERED OFF: The fact that officers remained on the property after being ordered to leave by a resident might make the entry more intrusive, but an order to leave does not make their presence unlawful if there was sufficient justification.58 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/08%3A_The_Plain_View_Doctrine/8.3%3A_Police_Trespassing.txt |
PETITIONER RESPONDENT
Oliver United States
LOCATION
Sugar Camp Road
DOCKET NO. DECIDED BY
82-15 Burger Court
LOWER COURT
United States Court of Appeals for the Sixth Circuit
CITATION
466 US 170 (1984)
ARGUED
Nov 9, 1983
DECIDED
Apr 17, 1984
ADVOCATES
Donna L. Zeegers on behalf of the Respondent
Thornton Wayne S. Moss on behalf of the Petitioner Maine
Frank E. Haddad, Jr. on behalf of the Petitioner
Oliver Alan I. Horowitz on behalf of the Respondent United States
Facts of the case
These are two consolidated cases involving the discovery of open marijuana fields as the result of unwarranted searches of privately owned land.
In the first case, Kentucky State police searched Ray E. Oliver's farm, acting on reports that marijuana was grown there. A gate marked with a "No Trespassing" sign surrounded the field.
Police found marijuana in the field about a mile from Oliver's home. Before trial, the United States District Court for the Western District of Kentucky suppressed evidence found in the search on the ground that Oliver had a reasonable expectation that his field would remain private. This expectation triggered the Fourth Amendment's protection against unreasonable searches and seizures. The Court of Appeals for the Sixth Circuit reversed under the open field doctrine. The open field doctrine states that a citizen's protection from unwarranted search does not extend to open fields.
In the second case, police searched the woods behind Richard Thornton's property after an anonymous tip. Police found two marijuana patches on Thornton's land. The Main Superior Court granted Thornton's motion to suppress evidence found in the search for the same reasons as the Oliver case. On appeal, the Supreme Judicial Court of Main affirmed.
Question
Does the open field doctrine apply when police officers knowingly enter privately owned fields without a warrant?
Conclusion
6–3 Decision
FOR AGAINST
Blackmun
White
Powell
Burger
O’Conner
Rehnquist
Marshall
Brennan
Stevens
Yes. In a 6-3 vote, Justice Lewis F. Powell, Jr. wrote for the majority, stating that the open field doctrine applies to both cases. Individuals cannot legitimately expect privacy for activities conducted out in the open except in the area immediately surrounding their house. Also, the act of police officers entering a privately owned field is not automatically a search for Fourth Amendment purposes even if it is a common law trespass. Oliver's case was affirmed, and Thornton's was reversed and remanded.
Justice Byron White wrote a special concurrence, saying that there was no need for the majority to deal with the expectation of privacy issue because a field is clearly not a "house" or an "effect" under the Fourth Amendment. Justice Thurgood Marshall wrote a dissent, contending that the law should protect private land that is marked as such against unreasonable searches and seizures. Justice William J. Brennan and Justice John P. Stevens joined Justice Marshall's dissent.
9.2: United States v. Martinez - Fuerte
PETITIONER RESPONDENT
United States Martinez-Fuerte
DOCKET NO. DECIDED BY
74 1560 Burger Court
LOWER COURT
United States Court of Appeals for the Ninth Circuit
CITATION
428 US 543 (1976)
ARGUED
Apr 26, 1976
DECIDED
Jul 6, 1976
ADVOCATES
Ballard Bennett for petitioner in No. 75-5387, by Mark L
Mark L. Evans
Charles M. Sevilla for respondent in No. 75-1560
Facts of the case
Martinez-Fuerte and others were charged with transporting illegal Mexican aliens. They were stopped at a routine fixed checkpoint for brief questioning of the vehicle's occupants on a major highway not far from the Mexican border.
Question
Do such stops violate the Fourth Amendment's proscription against unreasonable searches and seizures?
Conclusion
7 -2 Decision Majority Opinion By Lewis F. Powell, Jr.
FOR AGAINST
Stevens
Ginsburg
Souter
Scalia
Thomas
Breyer
Kennedy
Roberts
Alito
No, because if there is a reasonable collective suspicion, then individuals can be searched in the interest of public safety. Justice Lewis F. Powell, Jr., writing for the 7-to-2 majority, said: "The defendants note correctly that to accommodate public and private interests some quantum of individualized suspicion is usually a prerequisite to a constitutional search or seizure.... But the Fourth Amendment imposes no irreducible requirement of such suspicion."
9.3: California v. Greenwood
PETITIONER RESPONDENT
California Greenwood
DOCKET NO. DECIDED BY
86 684 Rehnquist Court
LOWER COURT
State appellate court
CITATION
486 US 35 (1988)
ARGUED
Jan 11, 1988
DECIDED
May 16, 1988
ADVOCATES
Michael J. Pear Argued the cause for the petitioner
Michael Ian Garey By appointment of the Court, argued the cause for the respondents
Facts of the case
Local police suspected Billy Greenwood was dealing drugs from his residence. Because the police did not have enough evidence for a warrant to search his home, they searched the garbage bags Greenwood had left at the curb for pickup. The police uncovered evidence of drug use, which was then used to obtain a warrant to search the house. That search turned up illegal substances, and Greenwood was arrested on felony charges.
Question
Did the warrantless search and seizure of Greenwood's garbage violate the Fourth Amendment's search and seizure guarantee?
Conclusion
7 -2 Decision for CA Majority Opinion By Byron R. White
FOR AGAINST
Blackmun
Stevens
White
O’Connor
Rehnquist
Brennan
Marshall
Voting 6 to 2, the Court held that garbage placed at the curbside is unprotected by the Fourth Amendment. The Court argued that there was no reasonable expectation of privacy for trash on public streets "readily accessible to animals, children, scavengers, snoops, and other members of the public." The Court also noted that the police cannot be expected to ignore criminal activity that can be observed by "any member of the public." | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/09%3A_Abondonment_Open_Fields_and_Border_Searches/9.1%3A_Oliver_v._United_States.txt |
A group of friends and I are going on a road trip in a month and I was wondering what are some of the best methods you have come across to secure our drugs? Posted on Reddit.com.
Most bigand small-time criminals have learned that the safest and most convenient place to hide their drugs, guns and
other incriminating evidence is often inside their cars and trucks. This is mainly because motor vehicles are relatively secure, highly mobile and, as an added bonus, they are fully protected by the Fourth Amendment. As one website advised its criminal readership: “Forget your house—your car is your most private place.”1
In the past, vehicles were even more attractive to criminals because the courts were suppressing a lot of evidence discovered inside them. This was because the rules pertaining to vehicle searches had become so “intolerably confusing”2 that officers often had to guess at whether they could search a vehicle, and could only speculate as to the permissible scope and intensity of these searches.
Who caused this important area of the law to fall into disorder? The prime suspects were members of the United States Supreme Court who had consistently failed to resolve the recurring conflict between the privacy rights of vehicle occupants and the needs of law enforcement.
But then one day in 1981, the Court issued an opinion named New York v. Belton in which it announced—or so we thought—that it was going to fix these problems.3 After acknowledging that officers needed vehicle search rules that were “straightforward,” “easily applied,” and “predictably enforced,” it announced just such a rule: Whenever officers make a custodial arrest of the driver or any occupant of a vehicle, they may, as a matter of routine, conduct a full search of the passenger compartment and its contents.
Many criminals and their attorneys were, of course, disappointed that the Court would choose such a coherent rule when it could have devised one that kept everyone guessing. But Belton became the law, and suddenly the subject of vehicle searches was much easier to understand and apply in the field.
But then in 2009, the Court—for reasons that are still bewildering—overturned Belton and replaced it with precisely the type of rule that Belton was designed to eliminate: one that was “highly sophisticated,” “qualified by all sorts of ifs, ands, and buts,” and “literally impossible of application by the officer in the field.”4 The case was Arizona v. Gant,5 and it was such a shifty opinion that the five justices who signed it claimed they had not actually overturned Belton when, in fact, that was exactly what they had done, and it was exactly what they had intended to do. As Justice Alioto said in his dissenting opinion, “Although the Court refuses to acknowledge that it is overruling Belton there can be no doubt that it does so.”
Although Gant was a regrettable opinion, it was not as devastating as first predicted. While probable cause to arrest an occupant of a vehicle would no longer justify a warrantless search of it, prosecutors discovered that in many cases in which officers had probable cause to arrest an occupant, they also had probable cause to search the vehicle for evidence of the crime. And because the Supreme Court has consistently upheld the rule that probable cause to search a vehicle will, in and of itself, justify a warrantless search of it, the rules pertaining to vehicle searches has remained fairly stable.
In this article, we will discuss the various types of vehicle searches, starting with the one we have just been discussing. Although it is sometimes called “The Automobile Exception,” it is more commonly known simply as a “probable cause search.”
Probable Cause Searches
The rule pertaining to probable cause searches is as straightforward as they come: Officers may search a vehicle without a warrant if they have probable cause to search it. Or, in the words of the Supreme Court, a warrantless vehicle search is legal if it was “based on facts that would justify the issuance of a warrant, even though a warrant has not actually been obtained.”6
Significantly, these searches are permitted even if officers had plenty of time to obtain a warrant,7 or if there were no exigent circumstances that required an immediate search,8 or even if the vehicle had already been towed and was sitting securely in a police garage or impound yard.9 As the Supreme Court observed in Michigan v. Thomas, “[T]he justification to conduct such a warrantless search does not vanish once the car has been immobilized.”10
Although the existence of probable cause is the main requirement, as we will now explain, there are actually four of them:
1. “VEHICLE”: The thing that was searched must fall within the definition of a “vehicle” which, in the context of probable cause searches, includes cars, SUVs, vans, motorcycles, bicycles, and boats.11 It also includes RVs and other motor homes except those that were being used solely as residences; e.g., on blocks.12 Furthermore, a vehicle may be searched even though it was immobile as the result of a traffic accident, a mechanical failure, a fire or, as noted earlier, because the vehicle was in police custody.13
2. PUBLIC PLACE: A probable cause search of a vehicle is permitted only if the vehicle was located in a public place or on private property over which the suspect could not reasonably expect privacy. For example, a car parked in the suspect’s garage could not be searched without a warrant or consent. What about cars parked on private driveways? In the past, they could be searched because it was generally agreed that people could not reasonably expect privacy in a driveway which is, by necessity, readily accessible from the street. In 2013, however, the Supreme Court rejected this reasoning and ruled that any nonconsensual entry onto a private driveway would require a warrant or consent if the officers’ objective was to obtain information.14 And because that is precisely the objective of conducting a vehicle search, an officer’s warrantless entry onto a driveway to search a car will ordinarily require a warrant.
3. PROBABLE CAUSE: See “Probable cause to search,” below.
4. SCOPE OF SEARCH: Officers must have restricted their search to places and things in which the evidence could reasonably be found. See “Scope and intensity of the search,” below.
Probable cause to search
In the context of vehicle searches, probable cause exists if officers were aware of facts that established a “fair probability” that contraband or other evidence of a crime was currently located inside the vehicle.15 This can be established by direct evidence (e.g., officer sees the evidence inside) or circumstantial evidence, such as the following.
PC TO ARREST > PC TO SEARCH
As discussed earlier, officers are no longer permitted to search a vehicle merely because they have probable cause to arrest the driver or other occupant. However, if they have probable cause to arrest an occupant for a crime that occurred recently, they will often have probable cause to search the car for the fruits and instrumentalities of that crime. In the words of the Supreme Court, “[A]s will be true in many cases, the circumstances justifying the arrest are also those furnishing probable cause for the search.”16 Here are two examples:
GETAWAY CAR: Probable cause to arrest an occupant of a car for a crime that occurred recently will ordinarily establish probable cause to search the vehicle for the fruits and instrumentalities of the crime. This often occurs when officers stop a car that had recently been used in a robbery or burglary, in which case they may have probable cause to search for weapons or tools that were used in the commission of the crime, stolen property, and clothing similar to that used by the perpetrator.17
DRUG SALES: Probable cause to arrest an occupant for drug sales will ordinarily provide probable cause to search for weapons and items that are commonly used to package and sell drugs.18
THE VEHICLE IS AN “INSTRUMENTALITY”: If officers have probable cause to believe that a vehicle, itself, was the means by which a crime was committed (e.g., hit-and-run, vehicular manslaughter, kidnapping) they may search it under an exception to the warrant requirement known as the “instrumentality exception.”19 As a practical matter, however, it is seldom necessary to rely on the instrumentality exception because, as discussed earlier, officers with probable cause to believe that a vehicle was an instrumentality of a crime will usually have probable cause to search it. Nevertheless, California courts continue to cite the instrumentality exception, especially in cases in which officers are looking for trace evidence such as DNA.20
INFERENCE BASED ON CLOSE ASSOCIATION
Probable cause to search for certain evidence in a vehicle may be based on the discovery of a thing or condition that is closely associated with such evidence. In other words, if items A and B are commonly found together, and if officers find A in the suspect’s possession, it may be reasonable to infer that he also possesses B. Thus, in discussing this principle, the court in People v. Simpson observed, “Illegal drugs and guns are a lot like sharks and remoras. And just as a diver who spots a remora is well-advised to be on the lookout for sharks, an officer investigating cocaine and marijuana sales would be foolish not to worry about weapons.”21 Some other examples:
DRUG CONTAINER > DRUGS
Seeing a distinctive container that is commonly used to store drugs will ordinarily warrant a search of it; e.g., bindles, tied balloons.22 But containers that are commonly used for a legitimate purpose will not satisfy this requirement; e.g., film canisters.23
DRUG PARAPHERNALIA > DRUGS
The presence of drug use or sales paraphernalia in a vehicle may establish probable cause to search it for drugs.24
ODOR OF DRUGS > DRUGS
A distinctive odor of drugs from inside the vehicle may establish probable cause to search it for drugs.25
K-9 ALERT > DRUGS
A K-9’s alert to the vehicle will ordinarily establish probable cause to search it for drugs.26
DUI DRUGS > DRUGS
If officers have probable cause to believe that the driver is under the influence of drugs, it is usually reasonable to infer he possesses drugs and paraphernalia.27
ALCOHOL ODOR > OPEN CONTAINER
Officers who smell fresh beer in a vehicle may infer there is an open container in the vehicle.28
AMMUNITION > FIREARMS
If officers see ammunition in the passenger compartment of a car, it is often reasonable to infer there is also a firearm inside.29
BURGLAR TOOLS > STOLEN PROPERTY
If officers saw burglar tools in a burglary suspect’s vehicle shortly after a burglary occurred, it may be reasonable to infer that property stolen in the burglary will also be found in the vehicle.30
SUSPICIOUS CIRCUMSTANCES
Although probable cause to search a vehicle will seldom be based on a single suspicious circumstance, there are several circumstances that will ordinarily convert reasonable suspicion to detain into probable cause to search.31 Some examples:
SECRET COMPARTMENT: Officers who had stopped a suspected drug trafficker saw indications of a secret compartment in the vehicle.32
SUSPICIOUS SPARE TIRE: In one case, a court ruled that grounds to search existed when, after officers stopped a car because they reasonably believed it was being used to transport drugs, they found an unusually heavy spare tire with a “flopping” sound coming from the inside.33
MASKING ODOR: Another indication that a car is being used to transport drugs is the presence of multiple air fresheners.34
STOLEN PROPERTY INDICATORS: In the vehicle of a suspected burglar, robber, or fence, officers saw property with obliterated serial numbers, store tags or anti-shoplifting devices, clipped wires, pry marks or other signs of forced removal.35 Another indication that property in a vehicle was stolen is that there was an unusually high quantity of it. This is especially significant if the property was of a type that is commonly stolen; e.g., TVs, cell phones, jewelry.36
STOLEN CAR INDICATIONS: Probable cause to believe that a car was stolen may be based in part— or sometimes entirely—on combinations of suspicious circumstances such as the following: failure to produce vehicle registration or driver’s license; missing or improperly attached license plate, indications of VIN plate tampering, switched plates, side window broken out, evasive driving, failure to stop promptly when lit up, evidence of ignition tampering, use of makeshift ignition key, driver gave false or inconsistent statements about his ownership or possession of the car, driver did not know the name of the registered owner.37
WHERE THERE’S SOME, THERE’S PROBABLY MORE:
When officers find contraband (e.g., stolen property, illegal weapons or drugs) in a vehicle, it is usually reasonable to believe there is more of it in the passenger compartment and the trunk. As the court said in People v. Stafford, “Being possessed of probable cause that the automobile contained stolen property and dangerous weapons, the officers were reasonably justified in continuing their search for other property that might have been stolen or other dangerous instrumentalities.”38
Scope and intensity of the search
If officers have probable cause to search a vehicle for evidence, they may search for it in the passenger compartment, the trunk, and all containers in which such evidence could reasonably be found.39 As the Supreme Court explained, when officers are conducting a probable cause vehicle search, “nice distinctions between . . . glove compartments, upholstered seats, trunks, and wrapped packages” must “give way to the interest in the prompt and efficient completion of the task at hand.”40 Thus, in upholding a search in People v. Gallegos the court observed, “The officers did not seek an elephant in a breadbox, but limited their search to areas that reasonably might have contained the [evidence].”41 Officers are not, however, required to confine their search to places and things in which the listed evidence is usually or commonly found; what is required is a reasonable possibility.42
SEARCHING OCCUPANTS: Officers may not search the clothing worn by the occupants. Instead, a search is permitted only if officers had probable cause to believe that the evidence was located in the person’s clothing.43 Thus, in U.S. v. Soyland the Ninth Circuit said, “There was not a sufficient link between Soyland [a passenger] and the odor of methamphetamine or the marijuana cigarettes, and his mere presence did not give rise to probable cause to arrest and search him.”44
SEARCHING CELL PHONES: As the result of California’s Electronic Communications Privacy Act, a search warrant is required to search cell phones and other electronic communications devices that are located in a vehicle; i.e., merely having probable cause is no longer sufficient.45 However, if officers believe they have probable cause to search the phone, they may seize it and seek a warrant.46 Furthermore, because a weapon might be disguised as a cell phone, officers may conduct a physical examination of its exterior and case.47
PERMISSIBLE INTENSITY OF THE SEARCH: Officers may conduct a “probing” or reasonably thorough search.48 Causing damage to the vehicle is permissible only if reasonably necessary and only if the damage was not excessive; e.g., OK to take paint samples from hit-and-run vehicle.49 Suggestion: If it will be necessary to damage the vehicle, seek a warrant if there is time.
Reasonable Suspicion Searches
Although officers may no longer search a vehicle merely because they had probable cause to arrest an occupant, they may search it for evidence of that crime if, in addition to having probable cause to arrest, they reasonably believed that evidence pertaining to that crime was located inside the vehicle; i.e., probable cause to search is not required.50 As the Supreme Court explained in Arizona v. Gant, “[C]ircumstances unique to the vehicle context justify a search incident to a lawful arrest when it is reasonable to believe evidence relevant to the crime of arrest might be found in the vehicle.”51 For example, in applying this rule, the courts have noted the following:
• “When a driver is arrested for being under the influence of a controlled substance, the officers could reasonably believe that evidence relevant to that offense might be found in the vehicle.”52
• “Given the crime for which the officer had probable cause to arrest (illegal possession of a firearm), it is reasonable to believe evidence relevant to the crime of arrest might be found in the vehicle,” such as ammunition or a holster.53
• “[T]he agents arrested Evans and Swanson for bank robbery and they had every reason to believe there was evidence of the offense in the green Cadillac.”54
As for the scope of the search, officers may search the entire passenger compartment and all containers inside it; i.e., they need not restrict the search to places and things in which the evidence might be found.55 It appears they may also search the trunk.56 As noted earlier, however, pursuant to the California Electronic Communications Privacy Act, officers may not search cell phones or other communications devices without a warrant or consent.57 Instead, as noted earlier, if they believe they have probable cause to search it, they may seize it and apply for a warrant.58 They may also conduct a physical examination of the phone’s exterior and its case.59
Vehicle Inventory Searches
Unlike “investigative” vehicle searches based on probable cause or reasonable suspicion, vehicle inventory searches are classified as “community caretaking” searches because their main purposes are to (1) provide a record of the property inside the vehicle so as to furnish the owner with an accounting; (2) protect officers and others from harm if the vehicle happened to contain a dangerous device or substance; and (3) protect officers, their departments, and ultimately the taxpayers from false claims that property in the vehicle was lost, stolen, or damaged.60
Despite their obvious benefits, vehicle inventory searches are subject to certain restrictions that help ensure that they are not used as a pretext to conduct an investigative search for evidence.61 Specifically, officers may conduct a search only if:
(1) TOWING WAS REASONABLY NECESSARY: The officer’s decision to impound or store the vehicle was reasonable under the circumstances.
(2) STANDARD SEARCH PROCEDURES: The search was conducted in accordance with departmental policy or standard procedure.
Towing reasonably necessary
Because an inventory search can be conducted only if officers need to take temporary custody or control of the vehicle, the first requirement is that towing must have been reasonably necessary under the circumstances.62 As the Court of Appeal explained, “[T]he ultimate determination is properly whether a decision to impound or remove a vehicle, pursuant to the community caretaking function, was reasonable under all the circumstances.”63 This does not mean that towing must have been imperative. Instead, as the First Circuit explained, it must have been reasonable:
Framed precisely, the critical question is not whether the police needed to impound the vehicle in some absolute sense, but whether the decision to impound and the method chosen for implementing that decision were, under all the circumstances, within the realm of reason.64
NO LEAST INTRUSIVE MEANS TEST: In determining whether towing was reasonably necessary, it is immaterial that there might have been a less intrusive means of protecting the vehicle or its contents; e.g., by locking the vehicle and leaving it at the scene.65 Instead, what matters is whether the decision was reasonable.66 Furthermore, if towing was reasonably necessary, it is immaterial that the officers’ decision to tow was based in part on their suspicion that the vehicle contained evidence.67
EXAMPLES OF REASONABLE NECESSITY: While it would be impractical to provide a comprehensive list of those situations in which the decision to tow a vehicle would be considered “reasonable,” the following usually fall into that category:
TRAFFIC HAZARD: The vehicle constituted a traffic hazard or obstruction.69
ABANDONMENT: The vehicle had been abandoned.69
DRIVER INCAPACITATED: The driver had become incapacitated by injuries or illness.70
DRIVER ARRESTED + NECESSITY: While the Vehicle Code authorizes towing when officers have arrested the driver or other person in control of the vehicle,71 the courts permit towing only if it was reasonably necessary.72 For example, towing would ordinarily be permitted if the vehicle was away from the arrestee’s home, especially if it was located in an area with a significant threat of theft or vandalism, or if the car was in an isolated area, or if the car could not be secured.73 Towing would not ordinarily be reasonable if the vehicle could have been parked and secured in a safe place.74 Similarly, there would ordinarily be no need to tow a vehicle if the arrestee wanted a friend at the scene to take possession, and the friend was licensed and insured.75
UNOCCUPIED CAR NEEDING PROTECTION: Even if the Vehicle Code did not expressly authorize towing, officers may do so if towing was reasonably necessary to protect the vehicle or its contents from theft or damage.76 If towing was necessary, it is immaterial that the vehicle was located on private property.77
TOWING FORFEITED VEHICLE: Officers may tow a vehicle that was subject to forfeiture.78
EXPIRED REGISTRATION: The Vehicle Code authorizes towing if (1) the vehicle was on the street or a public parking facility; and (2) the registration expired over six months earlier, or the registration sticker or license plate was issued for another vehicle or was forged.79
SUSPENDED OR REVOKED DRIVER’S LICENSE: The Vehicle Code states that officers may impound a vehicle if the driver was given a notice to appear for violating Vehicle Code sections 14601 or 12500.80 But if the driver was cited for driving on a suspended or a revoked license there is some uncertainty as to whether officers may tow the vehicle if there was a licensed and insured passenger on the scene who was willing to drive. As noted earlier, if the driver had been arrested, officers must ordinarily permit such a passenger to take the vehicle because there is no apparent justification for towing when the driver is going to jail and cannot drive off after officers have left. The situation might be viewed differently, however, if the driver was going to be cited and released. This is because it is possible, (maybe even probable considering his demonstrated contempt for California’s licensing statutes) that the driver will drive anyway after officers depart. Thus, in People v. Burch 81 the court upheld towing in such a situation because the officer testified he usually did so “to prevent the cited driver from simply getting back into the vehicle and driving away.”
Search procedures are reasonable
In addition to proving that the decision to tow was reasonable, officers must prove that the search was conducted in accordance with “standardized criteria or established routine.”82 The purpose of this requirement is to help ensure that inventory searches are not conducted for the purpose of “general rummaging in order to discover incriminating evidence.”83 As the Second Circuit observed in U.S. v. Lopez:
[W]hen a police department adopts a standardized policy governing the search of the contents of impounded vehicles, the owners and occupants of those vehicles are protected against the risk that officers will use selective discretion, searching only when they suspect criminal activity and then seeking to justify the searches as conducted for inventory purposes.84
This does not mean the criteria and routine must be set forth in elaborate specificity. As the First Circuit pointed out, this would be impractical:
Virtually by definition, the need for police to function as community caretakers arises fortuitously, when unexpected circumstances present some transient hazard which must be dealt with on the spot. The police cannot sensibly be expected to have developed, in advance, standard protocols running the entire gamut of possible eventualities. Rather, they must be free to follow sound police procedure, that is, to choose freely among the available options, so long as the option chosen is within the universe of reasonable choices.85
Keep in mind that officers are not required to prove that, under the circumstances in each case, it was reasonable to conduct an inventory search of the vehicle. This is because, as discussed earlier, it is settled that inventory searches are always reasonable whenever a vehicle will be towed.86 As the Ninth Circuit observed, “[I]t is undisputed that once a vehicle has been impounded, the police may conduct an inventory search.”87
As we will now explain, there are two ways in which officers and prosecutors can prove that a search was conducted in accordance with standardized policy.
WRITTEN DEPARTMENTAL POLICY: If a department has a written policy in which it defines the permissible scope and intensity of its inventory searches, prosecutors can satisfy the standardization requirement by introducing a copy of the policy into evidence after laying the necessary foundation by, for example, having the searching officer identify it. What should be included in such a policy? In most cases, the following will suffice:
GENERAL SCOPE AND INTENSITY: The policy need only specify the general areas and things in the vehicle that should be searched in order to locate and identify items that need to be included in the inventory,88 such as the following: the passenger compartment, including the glove box, console, under the seats;89 the trunk,90 including under the spare tire;91 all open and closed containers including containers that did not belong to the driver or owner of the vehicle;92 and the engine compartment.93 The policy may also authorize a search of motorcycles,94 rental cars,95 and any property that officers turn over to a third party, such as the driver’s friend.96 If the vehicle contains so much property that a listing of each item would take an excessive amount of time, the policy may permit officers to photograph the property instead.97 The policy need not require a listing of every object in the vehicle.98
OFFICER DISCRETION IS PERMITTED: The policy may permit officers to exercise discretion in determining what to search, but officers must exercise their discretion based on community caretaking objectives—not investigative interests.99 As the Supreme Court explained, “A police officer may be allowed sufficient latitude to determine whether a particular container should or should not be opened in light of the nature of the search and characteristics of the container itself.”100
READING DOCUMENTS: The policy may require or permit officers to read documents in the vehicle,101 and to look through notebooks and other multipage documents to “ensure that there was nothing of value hidden between the pages.”102
NO DAMAGE: The policy must not authorize officers to damage or destroy parts of the vehicle.103 CHP 180 FORMS: In lieu of a written policy as to the scope and intensity of the search, law enforcement agencies may satisfy the “standardization” requirement by mandating that their officers complete a CHP 180 form.104 This form requires, among other things, that officers list all “property” in the vehicle, including radios, tape decks, firearms, tools, and ignition keys. It also requires a description of all damage to the vehicle.
UNWRITTEN DEPARTMENTAL POLICY: Although it is usually better to have a written policy, a department may verbally disseminate a policy that will meet the above requirements. As the court explained in U.S. v. Tackett, “Whether a police department maintains a written policy is not determinative, where testimony establishes the existence and contours of the policy.”105 Similarly, the California Supreme Court pointed out that the Fourth Amendment “does not require a written policy governing closed containers but the record must at least indicate that police were following some ‘standardized criteria’ or ‘established routine.’”106
For example, in People v. Green 107 the Court of Appeal ruled that proof of a standardized policy was sufficient when the officer testified that she “considered the inventory search to be a natural consequence following the decision to impound defendant’s automobile. Although she did not use the magic words ‘standard procedure,’ her matterof-fact response indicates that an inventory search following impound of the vehicle is standard department procedure.”
Here’s another example of an officer’s testimony that satisfied the standardization requirement:
DA: What was your purpose of doing the inventory search; why did you do it?
Ofc: Policy of Moss Point Police Department, when you arrest someone out of their vehicle, you tow it and do an inventory search of their personal belongings and items left in the vehicle for the protection of the city.
DA: Is that standard operating procedures?
Ofc: Yes, ma’am.
DA: And is the policy, whether written or unwritten, of the police department to do that in every case?
Ofc: Yes, ma’am.
DA: And you said it was to protect the City of Moss Point or the police department. What do you mean by that?
Ofc: Well, so the person that’s arrested doesn’t come back and say, well, I had a five thousand dollar stereo, or five hundred dollars and now it’s missing.”
In contrast, in People v. Aguilar 108 the Court of Appeal ruled that an inventory search was unlawful because the officer testified that “he impounded 90 percent of the time; he had not seen the [departmental] policy; and one of the reasons he impounded Aguilar’s car was to look in the trunk.” Said the court, “It is clear from [the officer's] testimony that the arrest and the impound were for “an investigatory police motive.”
Protective Vehicle Searches
When officers have detained or arrested an occupant of a vehicle, a weapon in the passenger compartment can be almost as dangerous to them as a weapon in his waistband. For this reason, officers may conduct a protective search of the vehicle if both of the following circumstances existed:
(1) Officers reasonably believed there was a “weapon” inside the vehicle.
(2) The detainee or arrestee had potential access to the passenger compartment.
If these circumstances existed, officers may seize any weapons in plain view,109 and may also search the passenger compartment for additional weapons.110 They may not, however, search the trunk unless they develop grounds to conduct a probable cause search of it.111
Keep in mind that, if these circumstances existed, officers will not be required to prove that the detainee also presented a danger to them. For example, in People v. Lafitte 112 sheriff ’s deputies in Orange County made a traffic stop on Lafitte at about 10:15 P.M. because one of his headlights was not working. While one of the deputies was explaining the situation to Lafitte, the other shined a flashlight inside the car and saw a knife on the open door of the glove box. The deputy seized the knife, then conducted a protective search of the passenger compartment for additional weapons. During the search, he found a handgun. Although it was not illegal to have such a knife in a vehicle, and although Lafitte had been cooperative throughout the detention, the court ruled that the search was justified because “the discovery of the weapon” provided “a reasonable basis for the officer’s suspicion.”
Officers are not, however, required to prove that, in addition to the presence of a weapon, the detainee appeared to present a danger to them. Still, it is a circumstance that should be cited because it would help prove that a protective vehicle search was necessary, just as it is a relevant circumstance in determining whether a pat search was necessary;113 e.g., the detainee had a history of violence against officers, or he was hostile, or his behavior was unpredictable because it appeared he was under the influence of drugs or alcohol.114
“Weapon” defined
There are two types of weapons that will justify a protective search: (1) a conventional weapon; and (2) an object that, based on circumstantial evidence, is being used as a weapon. In some cases, the presence of a weapon may also be inferred based on the suspect’s behavior.
CONVENTIONAL WEAPONS: An officer’s observation of any type of conventional weapon in plain view (such as a firearm, knife, brass knuckles, nunchakus) will, of course, justify a protective vehicle search. This is true even if the weapon was possessed lawfully; e.g., a “legal” knife.115
VIRTUAL WEAPONS: A virtual weapon is essentially any object that reasonably appeared as if it was being used as a weapon, even though it was manufactured for another purpose. Examples include baseball bats, hammers, crow bars screwdrivers, and box cutters. How can the courts determine the intended use of an object? Like most things, it is based on the totality of circumstances, especially the location of object, its proximity to the suspect, and especially the ease with which it can cause physical harm to people.116
BEHAVIOR INDICATING PRESENCE OF WEAPON: Based on the law pertaining to pat searches, an officer’s belief that there was a weapon in the passenger compartment may be based on the suspect’s behavior and other circumstantial evidence.117
For example, in People v. King 118 two San Diego police officers stopped King for driving with expired registration. As one of them was walking up to the driver’s window, he saw King “reach under the driver’s seat,” at which point he heard the sound of “metal on metal.” In court, the officer testified that, based on these circumstances, he “feared for the safety of his partner and himself,” especially because “there was increased gang activity in the area.” After ordering King to exit, the officer looked under the front seat and found a .25-caliber semiautomatic handgun. In ruling that the officer reasonably believed there was a weapon under the seat, the court said, “[I]n addition to King’s movement, we have the contemporaneous sound of metal on metal and the officer’s fear created by the increased level of gang activity in the area.”
Potential access
If officers reasonably believed that a weapon was inside the vehicle, a protective search will be permitted only if the detainee or arrestee had not yet been subjected to a “full custodial arrest” and was therefore able to “gain immediate control” of the weapon. When that happens, said the Supreme Court, a protective vehicle search is permitted because “the officer remains particularly vulnerable” and the officer “must make a quick decision as to how to protect himself and others from possible danger.”119 It should be noted that defense attorneys have sometimes cited Arizona v. Gant 120 as authority for prohibiting protective vehicle searches unless the detainee or arrestee had actual access to the passenger compartment at the time the search occurred. But Gant’s requirement of actual access pertained to searches incident to arrest, and there is no logical reason that this requirement should be imported into the field of protective searches because officers do not ordinarily have as much control over detainees or those arrestees who not been subjected to a full custodial arrest.
Searches for ID
There is a type of warrantless vehicle search that is similar to, but distinct from, probable cause searches: searches for identification and related documentation. It is, of course, settled that officers who have stopped a vehicle for a traffic violation may inspect the driver’s license, vehicle registration, rental forms, and proof of insurance.121 Because they also have probable cause to believe that such documents will be found in the vehicle, it has been argued that officers who have made a traffic stop should themselves be able to conduct a search for the documents. The courts have, however, consistently rejected these arguments mainly because there will usually be no reason to prohibit the driver from doing so.
Officers may, however, search for such documentation if they reasonably believed it would have been impractical or dangerous for them to permit the driver or another occupant to conduct the search, or if officers reasonably believed the vehicle had been stolen or abandoned.122 For example, the courts have upheld warrantless searches for documentation under the following circumstances:
• The driver was unable to produce a driver’s license and said he did not know where the registration certificate was located because he did not own the vehicle.123
• The driver abandoned the car and the passenger (a parolee) said he didn’t know the owner.124
• The driver said the car belonged to one of his passengers, but the passengers claimed they were hitchhikers.”125
• An armed and dangerous driver fled from officers and they reasonably believed the vehicle contained evidence that would help them locate him.126
• The driver was stopped at 2 A.M. for driving erratically; there were two other men in the vehicle, one of whom had been hanging out a window and waving a whiskey bottle.127
Two other things should be noted. First, before beginning the search, officers may order the occupants to exit.128 Second, the search must be limited to places and things in which such documents may reasonably be found; e.g., the glove box, above the visor, under the seats.129 But the search need not be limited to places in which such documents are “usually” or “traditionally” found.130 Finally, in the absence of probable cause, officers may not search the trunk for ID.131
Other Vehicle Searches
There are five other types of warrantless vehicle searches that, although they do not require much discussion, should be noted.
CONSENT SEARCHES: The owner of a vehicle, or a person who has the owner’s permission to drive it, may ordinarily consent to a search of both the vehicle and its contents.132 There is, however, an exception: Officers may not search a container in the vehicle if it reasonably appeared that someone other than the consenting person had exclusive control or access to it.133
PROBATION AND PAROLE SEARCHES: Officers may ordinarily search the vehicle pursuant to the terms of probation or parole if they were aware that the owner or the driver was on parole or was on probation which contained a search clause authorizing vehicle searches or searches of property under the probationer’s control. In addition to searching property under the control of the probationer or parolee, officers may search property belonging to a passenger if they reasonably believed the parolee could have stowed his belongings in the property when he became aware of “police activity.”134
EXIGENT CIRCUMSTANCES: Under the exigent circumstances exception to the warrant requirement, officers may forcibly enter a vehicle if it was reasonably necessary to protect a person from imminent harm, or protect property from imminent damage; e.g., child locked in vehicle, an occupant was sick or injured, gun or dangerous chemical was inside. It may also be necessary to enter a vehicle that has been burglarized or is otherwise insecure for the purpose of locking it or searching for registration that will enable officers to notify the owner.
SEARCHES BY VEHICLE THEFT INVESTIGATORS: Officers whose primary responsibility is to investigate vehicle theft may search unoccupied vehicles to determine the lawful owner if the vehicle was located “on a highway or in any public garage, repair shop, terminal, parking lot, new or used car lot, automobile dismantler’s lot, vehicle shredding facility, vehicle leasing or rental lot, vehicle equipment rental yard, vehicle salvage pool, or other similar establishment.”135
VIN SEARCHES: Regardless of whether there are grounds to do so, officers may look through the windshield of a vehicle to inspect the VIN plate located on the dash if the car is located in a public place. If the vehicle was stopped for a traffic violation, and if the VIN plate was covered, officers may enter the vehicle and remove the covering in order to record the VIN number.136 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/10%3A_Vehicle_Searches/10.1%3A_Vehicle__Searches.txt |
PETITIONER RESPONDENT
Arizona Rodney Joseph Gant
LOCATION
2524 N. Walnut
DOCKET NO. DECIDED BY
07-542 Roberts Court
LOWER COURT
Arizona Supreme Court
CITATION
556 US 332 (2009)
GRANTED
Feb 25, 2008
ARGUED
Oct 7, 2008
DECIDED
Apr 21, 2009
ADVOCATES
Josep h T . Maziarz argued the cause for the petitioner
Anthony A. Yang Assistant to the Solicitor General, Department of Justice, for the United States, as amicus curiae, supporting the petitioner
Thomas F. Jacobs argued the cause for the respondent
Facts of the case
Rodney Gant was apprehended by Arizona state police on an outstanding warrant for driving with a suspended license. After the officers handcuffed Gant and placed him in their squad car, they went on to search his vehicle, discovering a handgun and a plastic bag of cocaine. At trial, Gant asked the judge to suppress the evidence found in his vehicle because the search had been conducted without a warrant in violation of the Fourth Amendment's prohibition of unreasonable searches and seizures. The judge declined Gant's request, stating that the search was a direct result of Gant's lawful arrest and therefore an exception to the general Fourth Amendment warrant requirement. The court convicted Gant on two counts of cocaine possession. The Arizona Court of Appeals reversed, holding the search unconstitutional, and the Arizona Supreme Court agreed. The Supreme Court stated that exceptions to the Fourth Amendment warrant requirement must be justified by concerns for officer safety or evidence preservation.
Because Gant left his vehicle voluntarily, the court explained, the search was not directly linked to the arrest and therefore violated the Fourth Amendment. In seeking certiorari, Arizona Attorney General Terry Goddard argued that the Arizona Supreme Court's ruling conflicted with the Court's precedent, as well as precedents set forth in various federal and state courts.
Question
Is a search conducted by police officers after handcuffing the defendant and securing the scene a violation of the Fourth Amendment's protection against unreasonable searches and seizures?
FOR AGAINST
Stevens
Ginsburg
Souter
Scalia
Thomas
Breyer
Kennedy
Roberts
Alito
Conclusion
5–4 Decision
Majority Opinion By John Paul Stevens
Yes, under the circumstances of this case. The Supreme Court held that police may search the vehicle of its recent occupant after his arrest only if it is reasonable to believe that the arrestee might access the vehicle at the time of the search or that the vehicle contains evidence of the offense of the arrest. With Justice John Paul Stevens writing for the majority, the Court reasoned that "warrantless searches are per se unreasonable" and subject only to a few, very narrow exceptions. Here, Mr. Gant was arrested for a suspended license and the narrow exceptions did not apply to his case. Justice Scalia wrote separately, concurring. Justice Samuel A. Alito dissented and was joined by Chief Justice John G. Roberts, and Justices Anthony M. Kennedy and Stephen G. Breyer. He argued that the majority improperly overruled its precedent in New York v. Belton which held that "when a policeman has made a lawful arrest… he may, as a contemporaneous incident of that arrest, search the passenger compartment of that automobile." Justice Stephen G. Breyer also wrote a separate dissenting opinion, where he lamented that the court could not create a new governing rule. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/10%3A_Vehicle_Searches/10.2%3A_Arizona_v._Gant.txt |
Parole is a risky business. Recidivism is high.1
For some people, committing crimes is a way of life, almost part of the daily routine. As the Supreme Court explained, such people “have necessarily shown a lapse in the ability to control and conform their behavior to the legitimate standards of society by the normal impulses of selfrestraint.”2 In discussing this subject, the writers of the book Inside The Criminal Personality summarized one of their findings as follows: “If we were to calculate the total number of crimes committed by all the men with whom we worked, it would be astronomic.”3
This is, of course, the main reason that many— maybe most—probationers and all parolees are required to submit to warrantless searches as a condition of their release from custody.4 The theory is that search conditions help “minimize the risk to the public safety”5 because the probationer or parolee will be “less inclined” to possess the fruits and instrumentalities of crime, such as weapons.6 And for those who continue to commit crimes while on the outside, search conditions provide another valuable public service: they help put them back inside. Despite this, the law pertaining to probation and parole searches has been a source of much confusion thanks mainly to several dubious published opinions by some appellate courts. But, as we will explain in this article, thanks to more recent decisions by the United States Supreme Court and the California Supreme Court, most of this confusion has been eliminated.
We will begin by briefly discussing the fundamentals of probation searches, parole searches, and the newer Postrelease Community Supervision (PRCS) searches. Then we will cover the requirements for conducting each of these searches, their permissible scope and intensity, and the special requirements for searching homes, vehicles, and cell phones.
The Basics
PROBATION SEARCHES: When a defendant is convicted of a crime, the judge may grant probation if the defendant agrees to certain conditions which often include submission to warrantless searches.7 Unlike parole and PRCS searches, however, the scope of probation searches varies because it is determined by the sentencing judge and is based on the circumstances of each case. (This, of course, creates problems for officers, as we will discuss later.) Probation searches are deemed “consent” searches because the probationer is technically free to choose between accepting a search condition or serving time in jail or prison.8
PAROLE SEARCHES: In contrast to probationers, California parolees do not consent to search conditions. Instead, they are required to submit per statute. Furthermore, all parolees are subject to searches of the same places and things.9 This, too, will be discussed later.
PRCS SEARCHES: Under California’s Postrelease Community Supervision Act of 2011, people who have been convicted of certain lower-level felonies may be permitted to serve their prison sentences in a local county jail.10 Then, upon release, they will be supervised for up to three years by a county probation officer. Even though the person is not confined in a state prison or supervised by a parole officer, the Court of Appeal has ruled that his status is substantially the same as that of a parolee.11 (Because there is no significant difference between PRSC and parole searches, all further references to parole searches will include PRCS searches.)
Requirements
Although probation and parole searches differ in many ways, they share the same four basic requirements:
1. officers must have known that the target of the search was on parole or searchable probation,
2. the search must have furthered a legitimate law enforcement interest,
3. the officers must have confined their search to places and things they were expressly or impliedly permitted to search (see “Scope of the Search,” below), and
4. the search must have been reasonable in its intensity (see “Intensity of the Search,” below). As noted, there are additional requirements for conducting searches of homes, vehicles, and cell phones which we will discuss later.
Significantly, there is one thing that is not required for these searches: Officers are not required to justify the search by proving they had probable cause, reasonable suspicion, or any other level of proof that the probationer or parolee had violated the law or the terms of his release.12 This is because the main purpose of these searches is to give probationers and parolees an incentive to avoid drugs, weapons, and so forth. And one way to do this is to make them aware that they may be searched at any time for no reason whatsoever. As the California Supreme Court explained, “[T]he purpose of the search condition is to deter the commission of crimes and to protect the public, and the effectiveness of the deterrent is enhanced by the potential for random searches.”13 Regarding probation searches, it should be noted that a sentencing judge might require that officers possess at least a low level of proof that the probationer had committed some crime. But such a requirement is seldom imposed and it will not be implied.14
Knowledge of probation or parole status
The first requirement is that officers must have been aware that the target of the search was on parole or searchable probation.15 This is mainly because a search that is conducted without such knowledge is “wholly arbitrary” and “without any perceived limits to [the officers’] authority.”16
Legitimate law enforcement purpose
Even if officers had knowledge of the search condition, a warrantless search will not be upheld unless they conducted it for a legitimate law enforcement or rehabilitative purpose.17 The courts usually express this requirement in the negative; specifically, the search must not have been “arbitrary, capricious, or harassing.18 And this necessarily occurs if “the motivation for the search was unrelated to rehabilitative, reformative or legitimate law enforcement purposes.”19 In this section we will discuss the types of motivations that have been deemed “legitimate”.
ROUTINE SEARCHES: A search is legitimate if it was conducted as a matter of routine and its purpose was just to make sure the probationer or parolee was not carrying drugs, weapons, or instrumentalities of a crime.20 As the Supreme Court pointed out, “unexpected” and “unprovoked” searches provide information that affords “a valuable measure of the effectiveness of the supervision.”21
RANDOM SEARCHES: A probation or parole search is not “arbitrary” or “capricious” merely because it was unscheduled and was prompted by the sudden availability of the probationer or parolee (e.g., seeing him walking down a street). While it has been argued that such searches are “arbitrary” (i.e., depending completely on individual discretion) and “capricious” (i.e., sudden, impulsive), the courts permit—and even encourage—them.22
For example, in In re Anthony S.,23 officers in Ventura learned that several members of the “Ventura Avenue Gangsters” were on probation, and that the terms of probation included authorization to search their homes for stolen property and gang paraphernalia. So they searched the home of a member named Anthony and found handguns and other contraband. The trial judge ruled that the search was unlawful, claiming it was a “random” search in which the officers decided “let’s go search the gang members today.” But the court disagreed, ruling “the evidence shows that the officers were motivated by a law enforcement purpose; i.e., to look for stolen property, alcohol, weapons, and gang paraphernalia at the homes of the Ventura Avenue Gangsters members. This is a legitimate law enforcement purpose.”
INVESTIGATIVE SEARCHES: A search is not unlawful merely because officers suspected that a particular probationer or parolee had committed a new crime, and the objective of the search was to see if he possessed any evidence of the crime.24 This is because the commission of a new crime is necessarily a violation of probation or parole.25 As the California Supreme Court observed in People v. Stanley, “Clearly, investigation of defendant’s involvement in a murder would have a parole supervision purpose.”26 This probably sounds too obvious to warrant discussion, but the Ninth Circuit took a different position, and was admonished for it by the Supreme Court. This case was United States v. Knights.27
In Knights, Napa County sheriff’s deputies suspected that Knights committed a series of pipe bombings and other acts of vandalism against PG&E and Pacific Bell facilities. They also learned that Knights was on probation in a drug case, and that the terms of probation authorized, among other things, a search of his residence. So, in hopes of obtaining evidence of the crimes, deputies conducted a probation search of his apartment and found a detonation cord, bolt cutters, blueprints stolen from a building that had been bombed, and other evidence linking Knights to the crimes. As the result, Knights was convicted of conspiracy to commit arson and possession of an unregistered destructive device.
But in an especially absurd decision, the Ninth Circuit ruled the search was unlawful because its purpose was to obtain evidence that Knights had committed certain violent crimes, rather than ascertaining whether he was complying with the terms of probation. The Supreme Court was aghast, and it informed the Ninth Circuit that the public and law enforcement have a legitimate interest in determining whether probationers are bombing things, setting buildings on fire, or committing other less serious crimes.
PRETEXT RESIDENTIAL SEARCHES: A search of a home in which a probationer or parolee lives is pretextual if the officers’ sole objective was to obtain evidence against another occupant, such as a roommate. Thus, a pretext search is, by definition, an illegal search because its sole objective is to obtain evidence against the roommate, not the probationer or parolee.
Pretext searches are, however, rare since the officers’ investigation will seldom focus exclusively on the roommate. Instead, it is often reasonable for them to believe that probationers and parolees know about the criminal activities of the people they live with, and might even be assisting them.28
Dual purpose searches are not, however, without limitation. Specifically, officers who are conducting them will be required to limit their searches to common areas and places and things over which the probationer or parolee had sole or joint control. This subject is discussed in more detail in the section on the scope of probation and parole searches.
SEARCH AFTER ARREST, SUMMARY PROBATION REVOCATION OR PAROLE HOLD: The terms of probation and parole, including search terms, remain in effect even if the probationer or parolee had been arrested, was being held on a parole hold, or if his probation was summarily revoked.29 As the Ninth Circuit observed in Latta v. Fitzharris, a parole officer’s interest in inspecting a parolee’s home does not terminate upon his arrest, “if anything, it intensified.”30 Consequently, search conditions and other terms of probation and parole do not terminate until a court has held a hearing and, as the result, ordered the revocation of probation or parole.
For example, in People v. Hunter 31 the driver of a stolen car bailed out when officers signaled him to stop. After identifying Hunter as the driver, officers learned that he was back in prison awaiting a parole revocation hearing. They also learned that he had rented a storage unit. So they searched it pursuant to the terms of parole and found stolen property. On appeal, Hunter argued that the search could not be justified as a parole search because his “parole was violated and he had been physically returned to prison as the result of that violation. The court pointed out, however, that the terms of parole remained in effect because “Hunter was still a parolee until his parole was formally revoked.”
FREQUENT, PROLONGED, OR LATE NIGHT SEARCHES:
A probation or parole search might be deemed harassing (and therefore illegal) if it occurred after several unproductive searches with no reason to believe that a new one would be fruitful, or if it was conducted late at night or in the early morning hours and there was insufficient reason for such an intrusion.32 However, the court in People v. Clower ruled that “[s]ix searches over a fourto five-month period, without more, do not necessarily indicate harassment,”33 and the court in People v. Sardinas ruled that a second search one day after an unproductive search was not harassing because the circumstances surrounding the second search indicated the defendant might have resupplied.34
Scope of the Search
In the context of probation and parole searches, the term “scope” refers to the places and things that officers are permitted to search. As we will now discuss, the permissible scope of a search depends on whether it was a probation or parole search.
Scope of probation searches
Because there are no “standard” probation search conditions, the permissible scope of a probation search depends on what the sentencing judge wrote on the probation order. Thus, the Court of Appeal explained that “the officer must have some knowledge not just of the fact someone is on probation, but of the existence of a search clause broad enough to justify the search at issue.”35 Consequently, officers must have knowledge of the places and things that were included in the suspect’s probation order. This does not mean, however, that officers must have seen an actual copy of the court’s order. Instead, because certain combinations of searchable places and things appear regularly in probation orders, many counties have developed systems by which these combinations have been given code numbers which, in turn, are incorporated into police databases. The following are some examples.
“FULL” SEARCH: The most common search condition, sometimes called a “full” or “four-way,” typically authorizes a search of (1) the probationer, (2) his residence, (3) vehicles, and (4) other property under his control. Note that a “full” probation search is the same as a parole search, except that a vehicle search is implied by the terms of parole (i.e., property under the parolee’s control) while it is expressly authorized by the terms of probation.
“PROPERTY UNDER YOUR CONTROL”: A probation search condition that includes authorization to search property under the probationer’s control is tantamount to a four-way because “property under your control” includes his residence.36
LACK OF UNIFORM TERMINOLOGY AND CODING: Before going further, it is necessary to point out that California does not have a statewide coding system by which officers can determine from a computer terminal exactly what they may search.37 Some counties might have a good internal system but others (such as Alameda County) have conflicting and redundant codes that have emerged piecemeal over many years. Furthermore, some terms may lack precise definition.
For example, a judge might authorize searches of property under the probationer’s control because he or she thinks (correctly) that this authorizes searches of the probationer’s person, residence, vehicle, and personal property—all of which he “controls”.38 But another judge sitting at a motion to suppress might conclude that because the search condition did not expressly authorize searches of the probationer’s person, home, and vehicles, the scope of the search was limited to whatever personal property he happened to be carrying.39
This uncertainty could be eliminated if the California courts adopted a uniform listing of search terms and a coding system so that officers throughout the state could be certain of the permissible scope of the probation searches they conduct.
Scope of parole searches
Unlike probationers, all parolees are subject to the same search condition: “You and your residence and any property under your control may be searched without a warrant at any time by any agent of the Department of Corrections or any law enforcement officer.”40 It should be noted that, unlike California parole, the terms and conditions of federal parole will vary because they are imposed at the discretion of the sentencing judge.41 Thus, officers must ordinarily not conduct federal parole searches until they have confirmed that the parolee is subject to warrantless searches of the places and things they intend to search.
Intensity of the Search
The term “intensity” is used to describe how aggressive or intrusive the search may be. Since there is not much law on the subject, we have looked to cases covering the intensity of warranted searches, consent searches, and searches incident to arrest.
REASONABLY “THOROUGH” SEARCH: Searches of homes, vehicles and other places may be reasonably thorough because, as one court put it, a cursory search “is of little value.”42
NO DAMAGE OR DESTRUCTION: The search must not be destructive.43 “Excessive or unnecessary destruction of property in the course of a search,” said the Supreme Court, “may violate the Fourth Amendment, even though the entry itself is lawful.”44 However, if officers have probable cause to believe that evidence is hidden in a place or thing that must be damaged to seize it, there is authority for doing so.45
LENGTH OF SEARCH: The permissible length of the search will depend on the number and nature of the places and things that will be searched, the amount and nature of the evidence that the officers are seeking, and any problems that caused a delay.46
SEARCHES BY K9S: Officers may use a trained dog (e.g., drugor explosives-seeking) to help with the search. This is because a dog’s sniffing does not materially increase the intensity of the search.47
Special Requirements
In addition to the requirements discussed above, there are additional requirements that pertain to searches of homes, vehicles, and cell phones.
Searches of homes
As noted earlier, the terms of all parole searches expressly authorize the search of the parolee’s home. In contrast, some probation search agreements expressly authorize searches of homes and some do not. But even if a search of the home is not expressly authorized, officers have implied authority to do so if, as noted earlier, the terms of probation included authorization to search property under the probationer’s control.48
PROOF THAT PROBATIONER OR PAROLEE LIVES THERE:
Even if a residential search was expressly or impliedly authorized, officers may not search a residence unless they have “reason to believe”—much less than probable cause—that the probationer or parolee lives there. As the court said in People v Downey, “[A]n officer executing an arrest warrant or conducting a probation or parole search may enter a dwelling if he or she has only a ‘reasonable belief,’ falling short of probable cause to believe, the suspect lives there and is present at the time.”49
While some other federal circuit courts (including the Ninth Circuit) have ruled that probable cause is required,50 it doesn’t seem to matter which standard of proof is applied because officers usually have sufficient information about where the arrestee lives to satisfy both. In fact, we are unaware of any case in which a court ruled that an entry was illegal because the officers had reasonable suspicion but not probable cause.50
What constitutes “living” in a residence? Although this question has “given difficulty to many courts,”51 it generally occurs if the probationer or parolee has been spending the night there regularly, even if not every night.52 A probationer or parolee may also be deemed to be living in two or more residences at the same time;53 and motel guests “live” in the motel in which they are registered.54 On the other hand, the fact that the probationer or parolee stays in a home “occasionally” is insufficient.55
GENERAL PRINCIPLES: In determining whether officers had reasonable suspicion that the probationer or parolee lived in a certain residence, the courts will apply the following principles:
NO HYPERTECHNICAL ANALYSIS: The courts will consider the totality of circumstances known to the officers, and these circumstances will be analyzed by applying common sense, not hypertechnical analysis.56
MULTIPLE CIRCUMSTANCES: Although a single circumstance will sometimes suffice, in most cases it takes two or more.
LACK OF DIRECT EVIDENCE: The courts will take into account that the officers’ inability to obtain direct evidence that the probationer or parolee lives in a certain house may be the result of his attempt to prevent them from learning his whereabouts.57 But that doesn’t change the fact that reasonable suspicion is required.
FRIENDS MIGHT LIE: Because the friends of the probationer or parolee might lie, officers are not required to accept information from a less-thandisinterested source as to his place of residence.58
IF OFFICERS WERE WRONG: It is irrelevant that officers learned afterward that the probationer or parolee did not live in the house they entered. What counts is whether they reasonably believed so at the time.59
RELEVANT CIRCUMSTANCES: The following circumstances are relevant in determining whether there is sufficient reason to believe that a probationer or parolee was living in a particular residence:
LISTED ADDRESS: The address was listed as his residence on one or more forms that reasonably appeared to be current, such as a rental or lease agreement,60 hotel or motel registration,61 utility billing records,62 telephone or internet records,63 credit card application,64 employment application,65 post office records,66 DMV records,67 vehicle repair work order,68 jail booking records,69 bail bond application,70 police reports and probation and parole records.71
INFORMATION FROM OTHERS: A citizen informant or a police informant who has been tested or whose information has been corroborated notified officers that the probationer or parolee presently lived at the address.72
CELL PHONE DATA: Cell site location data for the probationer’s or parolee’s cell phone showed significant recurring contact with a cell tower located in the home’s service area.73
OBSERVATIONS BY OFFICERS, OTHERS: Officers, neighbors, or others repeatedly or recently saw
the probationer or parolee on the premises.74 It is especially significant that he was observed doing things that residents commonly do; e.g. taking out the garbage, chatting with neighbors, opening the door with a key.75
CAR PARKED OUTSIDE: A car that was owned or used by the probationer or parolee was regularly parked in the driveway, in front of the residence, or nearby.76
PRESENCE OF PROBATIONER/PAROLEE NOT REQUIRED: Unless the terms of probation stated otherwise, officers may conduct a search even though the probationer was not present.77 As for parolees, their presence is not required.
KNOCK-NOTICE: Officers must enter the premises in a “reasonable” manner.78 As the Court of Appeal explained in People v. Ureziceanu, “[T]he remaining policies and purposes underlying the statutory knocknotice provisions must be satisfied in the execution of a probation search of a residence.”79 Accordingly, officers must comply with the knock-notice requirements unless there is good cause to make an unannounced entry.
PROTECTIVE SWEEPS: Upon entering the premises, officers may conduct a protective sweep to locate any people who might constitute a threat.80
WHAT PLACES MAY BE SEARCHED: Officers may search all common areas such as the living room, kitchen, garage, and all other rooms and areas to which the probationer or parolee appeared to have sole or joint access or control.81 This is true regardless of the probationer’s or parolee’s assurances to the contrary.82 Officers may also search the curtilage; e.g., a garden, yards.83 Conversely, officers may not search places if there is “no basis for officers to reasonably believe the probationer has authority over those areas.”84
WHAT THINGS MAY BE SEARCHED: Officers may search a container or personal property inside a residence if they had reasonable suspicion that the probationer or parolee owned or accessed it solely or jointly with another occupant.85 Significantly, probable cause is not required.86 For example, the courts have ruled that officers reasonably believed that probationers or parolees had sole or joint control of the following property:
• A jewelry box on a dresser in the bedroom of a female probationer.87
• A “gender neutral” handbag on a bed in a home occupied by a male parolee and his girlfriend.88
• A paper bag in the parolee’s bedroom closet.89
• A stationery box in a drawer in the living room.90
• Trash under the kitchen sink.91
• The refrigerator in the kitchen.92
ARRESTING OCCUPANTS: Officers who enter a residence to conduct a probation or parole search may arrest anyone on the premises if there is probable cause to do so, regardless of whether probable cause existed at the time of entry or developed in the course of the search. In other words, neither a conventional nor a Ramey warrant is required to arrest a person inside a residence if officers have lawfully entered to conduct a probation or parole search.93
Searches of vehicles
The permissible scope of a vehicle search will depend largely on whether the probationer or parolee was the owner or driver, or whether he was merely a passenger.
DRIVER OR OWNER ON PROBATION OR PAROLE: If the probationer or parolee was driving the vehicle or owned it, officers may ordinarily search the following:
PROPERTY OWNED BY PROBATIONER OR PAROLEE: Property that the officers reasonably believed was owned by the probationer or parolee,94 or property over which the officers reasonably believed the probationer or parolee had the ability to exert control.95
PROPERTY BELONGING TO PASSENGER: Officers may search a container belonging to a passenger if they reasonably believed that the parolee could have stowed his personal belongings in the container when he became aware of police interest; e.g., he apparently became aware that he was being followed.96 However, in the absence of direct or circumstantial evidence that a male probationer or parolee attempted to stow property in a female passenger’s purse, the court might find that it was unreasonable to search the purse, especially if it was closed and “closely monitored” by the woman; e.g., it was at her feet.97
PASSENGER ON PROBATION OR PAROLE: If only a passenger was on parole or probation, officers may search “those areas of the passenger compartment where the officer reasonably expects that the parolee could have stowed personal belongings or discarded items when he became aware of police interest.98
Officers need not, however, “articulate specific facts indicating that the parolee has actually placed property or contraband in a particular location in the passenger compartment before searching that area.” As discussed above, however, a search of a purse may be unlawful if the probationer or parolee was a male. Finally, it is unsettled whether officers may search closed compartments in the vehicle (e.g., glove box, console) if the probationer or parolee was merely a passenger.99 Finally, officers may stop a car for the purpose of conducting a parole or probation search even though the person on parole or probation was only a passenger.100
Search of cell phones
As the result of California’s Electronic Communications Privacy Act (CalECPA), it appears that officers may not search a cell phone or other communications device pursuant to a probation or parole search condition. The reason is, although probation searches are deemed “consensual,” CalECPA requires something it calls “specific consent,” which it defines as “consent provided directly to the government entity seeking information.”101 This seems to mean that searches of electronic communications devices are not covered under the scope of a probation search because such consent is not given “directly” to officers. Instead, it is given directly to the sentencing judge in exchange for the judge’s agreement not to send the probationer directly to jail or prison.102 As for parole searches, there is simply nothing in CalECPA to indicate that communication devices may be searched pursuant to the “property under your control” search authorization.
Consequently, if officers want to search a communication device that is found within a searchable vehicle, and if they believe they have probable cause, they may seize the device and promptly apply for a warrant.103 They may also conduct a warrantless physical examination of its exterior and case because there are weapons on the market that are disguised as cell phones.104
11.2: Samson v. California
PETITIONER RESPONDENT
Donald Curtis Samson California
DOCKET NO. DECIDED BY
81-430 Roberts Court
LOWER COURT
State appellate court
CITATION
547 US 843 (2006)
ARGUED
Feb 22, 2006
DECIDED
Jun 19, 2006
GRANTED
Sep 27, 2005
ADVOCATES
Jonathan L. Marcus argued the cause for Respondent
Ronald E. Niver argued the cause for Respondent
Facts of the case
A police officer stopped and searched Samson on the street in San Bruno, California. The officer had no warrant and later admitted he had stopped Samson only because he knew him to be on parole. The officer found that Samson was in possession of methamphetamines. Samson was arrested and charged with drug possession in state court. At trial Samson argued the drugs were inadmissible as evidence, because the search had violated his Fourth Amendment rights. The trial court denied the motion and the state supreme court declined to hear the case.
Question
Did the Fourth Amendment prohibit the police from conducting a warrantless search of a person who was subject to a parole search condition, where there was no suspicion of criminal wrongdoing and the sole reason for the search was because the person was on parole?
Conclusion
6–3 Decision
FOR AGAINST
Ginsburg
Kennedy
Roberts
Alito
Scalia
Thomas
Stevens
Souter
Breyer
Majority Opinion by Clarence Thomas
No. In a 6-to-3 decision authored by Justice Clarence Thomas, the Supreme Court held that Samson " did not have an expectation of privacy that society would recognize legitimate." Parole allows convicted criminals out of prison before their sentence is completed. An inmate who chooses to complete his sentence outside of direct physical custody, however, remains in the the Department of Correction's legal custody until the conclusion of his sentence, and therefore has significantly reduced privacy rights. In this case, Samson had also been required, as a condition of his parole, to sign an agreement that he would be subject to search or seizure by a parole officer or other peace officer..., with or without a search warrant and with or without cause." This written consent to suspicionless searches, along with his already reduced privacy interests as a parolee, combined to make the search constitutional. Justices Stevens, Souter and Breyer dissented, arguing that parolees have an expectation of privacy greater than that of prisoners, which was violated by the search at issue in this case. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/11%3A_Probation_and_Parole_Searches/11.1%3A_Probation_and_Parole_Searches.txt |
Police officers are often forced to make split-second judgments in circumstances that are tense, uncertain and rapidly evolving.1
Most people would probably agree that officers who encounter exigent circumstances should do whatever is reasonably necessary to quickly defuse the situation, including making a forcible entry into a residence. Certainly, most people who pay taxes would insist upon it. And that is, in fact, the law in California and in most states. Except there’s a problem: Nobody is quite sure of what the term “exigent circumstances” encompasses.
Over the years, it has been variously defined as a situation in which there is a “compelling need for official action”2 or a condition in which “real, immediate, and serious consequences will certainly occur,”3 and an “immediate major crisis.”4 But the most concise and accurate definition was provided by the Seventh Circuit which said that the term “exigent circumstances” is merely “legal jargon” for an “emergency.”5
In addition to its fuzziness, the number of situations that qualify as exigent circumstances has expanded greatly. At first it was limited to imminent threats to public safety. But over time the courts started employing it in situations where the threatened harm was the destruction of evidence or the apprehension of fleeing suspects.6
And then the courts started to recognize an entirely new type of exigent circumstance that became known as “community caretaking” or sometimes “special needs.” These are essentially situations that are “totally divorced from the detection, investigation, or acquisition of evidence,”7 and which also did not rise to the level of a true emergency—and yet the officers believed they needed to act and their belief was objectively reasonable. As the Ninth Circuit observed, the term “exigent circumstances” has become “more of a residual group of factual situations that do not fit into other established exceptions [to the warrant requirement].”8
Another change in the law was the establishment of a simpler and more elastic test for determining whether a situation fell into the category of “exigent.” It is known as “The Balancing Test,” and that is where we will start.
The Balancing Test
In the past, a threat could qualify as an emergency only if officers had probable cause to believe it would materialize.9 The problem with this requirement was that, by focusing on whether there was sufficient proof that a threat existed, the courts would sometimes ignore the overall reasonableness of an officer’s belief that a threat existed. They would also sometimes disregard the reasonableness of the manner in which officers responded. For example, a judge who was only interested in whether there was probable cause to believe that some harm was about to occur would overlook such seemingly important circumstances as the magnitude of the threat, the likelihood that the threat would materialize, and whether the officers’ response to the situation was proportionate to the threat.
For these reasons, the Supreme Court decided to abandon the probable cause requirement and, as noted, replace it with a type of the balancing test. Specifically, it ruled that a search or seizure pursuant to the exigent circumstances exception to the warrant requirement would be lawful if the need for the officers’ response outweighed its intrusiveness.10 Or, as the Fourth Circuit put it, “As the likelihood, urgency, and magnitude of a threat increase, so does the justification for and scope of police preventive action.”11
One important consequence of this test (as opposed to a probable cause requirement) is that if the need for the intrusion was not high, officers might still be able to respond if they could to reduce the intrusiveness to their response.
There is, however, one exception to the rule that probable cause is not required. It pertains to forcible entries into homes which, by their very nature, are so highly intrusive that the need for such a response can outweigh its intrusiveness only if the officers had probable cause to believe the threat would materialize.12
The Need for Immediate Action
The first and most important step in applying the balancing test is to assess the strength of the need for an immediate search or seizure. In making this determination, the courts apply the following general principles.
The “reasonable officer” test
In evaluating the significance of a threat— whether it’s a threat to a person’s life, to an investigation, or to a community caretaking interest— the courts apply the “reasonable officer” test. This means they examine the circumstances from the perspective of the proverbial “reasonable” officer who, while he sometimes makes mistakes, is always able to provide a sensible explanation for his actions.13 “The core question,” said the Second Circuit, “is whether the facts, as they appeared at the moment of entry, would lead a reasonable, experienced officer to believe that there was an urgent need to render aid or take action.”14
Another way to apply this test is to think, “How would the public respond if the threat materialized but I did nothing or waited for a warrant?”15 As the Court of Appeal put it, “In testing reasonableness of the search, we might ask ourselves how the situation would have appeared if the fleeing gunman armed with a shotgun had shot and possibly killed other officers or citizens while the officers were explaining the matter to a magistrate.”60
Training and experience
Because an officer’s training and experience “can be critical in translating observations into reasonable conclusions,”17 the courts will also take into account the responding officers’ training and experience as it pertains to such matters.
Reliability of information
Unlike the probable cause test which focuses heavily on the reliability of the information upon which the officer’s judgment was made, the balancing test is more flexible . Instead, the importance of reliable information decreases as the need for immediate action increases.18 Thus, in applying the balancing test in Florida v. J.L., the Supreme Court said, “We do not say, for example, that a report of a person carrying a bomb need bear the indicia of reliability we demand for a report of a person carrying a firearm before the police can constitutionally conduct a frisk.”19 Similarly, the Eleventh Circuit said that “when an emergency is reported by an anonymous caller, the need for immediate action may outweigh the need to verify the reliability of the caller.”20 It should also be noted that the existence of conflicting information as to the nature or scope of a threat does not necessarily eliminate the need for immediate action.21
Magnitude of potential harm
It is not surprising that the most weighty of all the relevant circumstances is the magnitude of the potential harm that might result if the officers delayed taking action. As the Ninth Circuit explained, “[W]hether there is an immediate threat to the safety of the arresting officer or others, the most important factor” is the magnitude of the potential threat.22 We will discuss this subject later in more detail.
Harm is “imminent”
The courts often say the threat must have been “imminent.” But this just means that the officers must have reasonably believed that the threat would have materialized before they would have been able to obtain a warrant.23 Thus, the Court of Appeal observed, “Imminent essentially means it is reasonable to anticipate the threatened injury will occur in such a short time that it is not feasible to obtain a search warrant.”24
The officers’ motivation
The officers’ motivation for taking action is unimportant in applying the balancing test in emergency aid and investigative emergency situations because their mental state has nothing to do with the magnitude of the threat or the reasonableness of their response.25 Thus, in an emergency aid case, Brigham City v. Stuart, the Supreme Court said, “It therefore does not matter here whether the officers entered the kitchen to arrest respondents and gather evidence against them or to assist the injured and prevent further violence.”26
In community caretaking cases, however, the officers’ motivation is significant because the word “caretaking” implies that the officers must have been motivated by a “caretaking” interest. As the California Supreme Court observed, “The defining characteristic of community caretaking functions is that they are totally unrelated to the criminal investigation duties of the police.”27
Manner of officer’s response
Regardless of the nature of the threat, a warrantless search or seizure will not be upheld if the officers did not respond to the threat in a reasonable manner. As the court explained in People v. Ray, “The officer’s post-entry conduct must be carefully limited to achieving the objective which justified the entry—the officer may do no more than is reasonably necessary to ascertain whether someone is in need of assistance or property is at risk and to provide that assistance or to protect that property.”28
Nevertheless, a delay is apt to be less significant if officers needed additional time to evaluate the situation or devise an appropriate response.29 As the California Supreme Court pointed out, “An officer is not required to rush blindly into a potential illicit drug laboratory and possibly encounter armed individuals guarding the enterprise, with no regard for his own safety just to show his good faith belief the situation is emergent.”30
Having examined the general principles that apply in determining whether exigent circumstances existed, we will now show how those principles are applied by the courts in the three categories of exigent circumstances: (1) imminent threat to a person or property, (2) community caretaking, and (2) investigative emergencies.
Imminent Danger to a Person
The need for rapid police intervention is greatest—and will almost always justify an immediate and intrusive response—when officers reasonably believed it was necessary to eliminate or address an imminent threat to a person’s health, safety, or sometimes property. “The most pressing emergency of all,” said the Court of Appeal, “is rescue of human life when time is of the essence.”31 Or as the Fourth Circuit put it, “[P]rotecting public safety is why police exist.”32
PERSON INJURED
That a person in a residence had been injured is not an exigent circumstance. But it becomes one if officers reasonably believed that the person’s life or safety were at risk, even if it was not life-threatening. For example, in Brigham City v. Stuart 33 police responded to a noise complaint at 3 A.M. and were walking up to the house when, as they passed a window, they saw four adults “attempting, with some difficulty, to restrain a juvenile,” at which point the juvenile “broke free and hit one of the adults in the face,” causing him to spit blood. The officers immediately opened the screen door, entered the residence and stopped the fight. They also arrested some of the adults for disorderly conduct and contributing to the delinquency of a minor.
The arrestees argued in court that the officers’ entry was illegal because there was no significant threat to anyone. Specifically, they claimed that “the injury caused by the juvenile’s punch was insufficient to trigger the so-called ‘emergency aid doctrine’” because the victim was not knocked unconscious or at least semi-conscious. In rejecting this argument, the Supreme Court pointed out that the “role of a peace officer includes preventing violence and restoring order, not simply rendering first aid to casualties; an officer is not like a boxing (or hockey) referee, poised to stop a bout only if it becomes too one-sided.”
Note that in Stuart, the existence of a threat was based on direct evidence. It most cases, however, it will be based on circumstantial evidence, such as the following:
SICK PERSON: Having learned that one of the occupants of an apartment was “sickly,” officers knocked on the door. They could hear several moans or groans from inside, but no one answered the door.34
UNRESPONSIVE PERSON: Officers were walking by the open door of a hotel room when they saw a man “seated on the bed with his face lying on a dresser at the foot of the bed.” They also saw “a broken, jagged piece of mirror” and “dark balls” which appeared to be heroin.35
SHOOTING OUTSIDE A HOME: Although the shooting apparently occurred just outside the home, there were bloodstains on the door indicating that “a bleeding victim had come into contact with the door, either by entering or by exiting the residence.”36
SHOOTING INSIDE A HOME: Officers responded to a report of a shooting inside a house. No one met them when they arrived and the house was dark, but there were two cars in the driveway and the lights outside were on. When no one answered the door, the officers went in through a window.37
IRRATIONAL AND VIOLENT: A man inside a motel room appeared to be “irrational, agitated, and bizarre”; he had been carrying two knives; his motel room was “in disarray, with furniture overturned, beds torn apart, and the floor littered with syringes and a bloody rag.”38
CHILD IN DANGER: An anonymous 911 caller reported that a child was being beaten by her parents; i.e., that it was happening now. When officers arrived they heard a man shouting inside the house, and then the man “bombarded” them with a “slew of profanities.”39
CHILD IN DANGER: Police received a report of “two small children left” alone at an apartment. No one answered door. A woman arrived and started to enter the apartment. An officer saw “considerable trash and dirty clothes strewn about the kitchen area,” and the woman was drunk.40
911 hangups
When people need immediate help, they usually call 911. But sometimes people who dial 911 hang up before the call is completed or while the dispatcher is trying to obtain information. In such cases, the 911 operator will have no way of knowing whether the connection was lost because the caller lost consciousness, or because someone was preventing the caller from completing the call, or if the caller was a child who was curious about what happens when someone dials 911. The operator cannot, however, ignore the call. As the Seventh Circuit observed, a “911 system designed to provide an emergency response to telephone tips could not operate if the police had to verify the identity of all callers and test their claim to have seen crimes in progress.”41
So, how can the responding officers determine whether a 911 hangup constitutes an emergency that would justify a search or seizure? While there are no easy answers, the courts often rule that such a response is justified if the officers saw or heard something upon arrival that was consistent with a call for help. For example, in applying this principle, the courts have noted the following:
• “[The] combination of a 911 hang call, an unanswered return call, and an open door with no responses from within the residence is sufficient to satisfy the exigency requirement.”42
• “Even more alarming, someone was answering the phone but immediately placing it back on the receiver.”43
• An “hysterical” man phoned the police at 5 A.M. and shouted, “Get the cops here now!” After the man gave his address, the phone was disconnected; the front door was ajar.44
• The woman who answered the door for the responding officers was nervous and gave them “obviously false statements,” which led them to believe “she had been threatened or feared retaliation should she give honest answers.”45
Domestic violence
On the subject of domestic violence calls, the Ninth Circuit noted that their volatility makes them “particularly well-suited for an application of the emergency doctrine.”46 Thus, in Tierney v. Davidson the Second Circuit said, “Courts have recognized the combustible nature of domestic disputes, and have accorded great latitude to an officer’s belief that warrantless entry was justified by exigent circumstances when the officer had substantial reason to believe that one of the parties to the dispute was in danger.”47
Still, as in 911 hangup cases, the courts seem to require some additional suspicious or corroborating circumstance before officers may enter without a warrant. “We do not suggest,” said the Ninth Circuit, “that domestic abuse cases create a per se exigent need for warrantless entry; rather, we must assess the total circumstances, presented to the law officer before a search, to determine if exigent circumstances relieved the officer of the customary need for a prior warrant.”48
For example, in People v. Pou 49 LAPD officers responded to a report of a “screaming woman” at a certain address. When they arrived, they could hear the “very loud” sound of people arguing. The officers knocked and announced several times, but no one responded. Finally, a man opened and door and the officers told him that they needed “to come in and look at the apartment to make sure everybody was okay.” When the man refused to admit them, they entered and conducted a protective sweep. “Under these circumstances,” said the court, “it was objectively reasonable for an officer to believe that immediate entry was necessary to render emergency assistance to a screaming female victim inside or to prevent a perpetrator from inflicting additional immediate harm to that victim or others inside the house.”
Similarly, in People v. Higgins 50 officers were dispatched at 11 P.M. to an anonymous report of a domestic disturbance involving “a man shoving a woman around.” No one responded to their knocking, but they saw a man inside the residence and then heard a “shout.” They knocked again, and a woman answered the door. “She was breathing heavily and appeared extremely frightened, afraid, very fidgety, and very nervous.” The officers also noticed a “little red mark” under one eye and “slight darkness under both eyes.” The woman tried to explain away the officers’ concern by saying that she was injured when she fell down some stairs, and that the noise from the fall might have prompted someone to call the police. When she said that her boyfriend had left, they knew she was lying (because they heard him “shout”), at which point they forcibly entered. In ruling the entry was lawful, the court noted that the woman “was extremely frightened and appeared to have been the victim of a felony battery. Moreover, [she] lied about being alone and gave the officers a suspicious story about having fallen down the stairs.”
In Pou and Higgins the officers had clearly seen and heard enough to reasonably believe that an immediate entry was justified by exigent circumstances. In many cases, however, the responding officers will have nothing more that a report of domestic violence from a 911 caller. Although some additional suspicious circumstance is ordinarily necessary before the officers may forcibly enter a home based on that alone, the courts have ruled that a 911 call may, in and of itself, justify a less intrusive response, such as trespassing. This is because it is common knowledge that 911 calls are traced and recorded, and therefore people who phone 911 instead of a non-emergency line are (at least to some extent) leaving themselves exposed to identification even if they gave a false name or refused to identify themselves.51 As the Supreme Court pointed out, “A 911 call has some features that allow for identifying and tracing callers, and thus provide some safeguards against making false reports with immunity.”52
For example, in U.S. v. Cutchin the D.C. Circuit upheld a car stop based solely on a 911 report that the driver had a sawed-off shotgun and a .38 caliber pistol at his side. In such cases, said the court, so long as the caller did not appear to be unreliable, “a dispatcher may alert other officers by radio, who may then rely on the report, even though they cannot vouch for it.”53
Missing persons
The courts have usually upheld forcible entries into a home for the purpose of locating a missing person when (1) the officers reasonably believed the report was reliable, (2) the circumstances surrounding the disappearance were sufficiently suspicious, and (3) there was reason to believe that an immediate warrantless entry was necessary to confirm or dispel their suspicions. Two examples:
In People v. Rogers 54 a woman notified San Diego police that a friend named Beatrice had been missing, that she was living with Rogers in an apartment complex that he managed and, even though Beatrice had been missing for three weeks, Rogers had refused to file a missing person report. In addition, she had previously heard Rogers threaten to lock Beatrice in a storage room in the basement. An investigator phoned Rogers who claimed that Beatrice had been missing for only a week or so, at which point Rogers said he “had to go,” and quickly hung up. Later that day, the investigator and uniformed officers went to the apartment and spoke with Rogers who claimed that Beatrice might have gone to Mexico “with someone.” The investigator asked if he could look in the storage room just to confirm that she was not being held there. At that point, Rogers’ “neck started to visibly throb” and he said no. The investigator then forcibly entered and found Beatrice’s remains. Rogers was charged with her murder. In ruling that the entry was justified, the court pointed out, among other things, Rogers’ “noticeable lack of concern over the whereabouts of his child’s mother” and his “physical reaction” when the investigator mentioned his threat to lock Beatrice in the storage room.
In People v. Macioce, 55 some friends of Mr. and Mrs. Macioce notified San Jose police that the couple was missing. The friends were especially concerned because the Macioces missed a regular church meeting which they usually attended, and also because Mr. Macioce failed to appear for a knee operation. They also said the Macioce’s car was parked in the carport but, during the past two days, they had knocked on the door of the house several times but no one responded and the mail was piling up. When the officers also received no response at the front door, they entered the apartment and discovered the body of Mr. Macioce who, as it turned out, had been killed by Mrs. Macioce. In rejecting Mrs. Macioce’s motion to suppress everything in the house (including her husband’s corpse) the court said the warrantless entry “was eminently reasonable.”
Drug labs
An illegal drug lab in a home or business will constitute an exigent circumstance if officers were aware of facts that reasonably indicated that it posed an imminent threat.56 This requirement is automatically satisfied if officers reasonably believed that the lab was being used to manufacture meth or PCP because the chemicals used to produce these substances tend to explode.57
What about the odor of ether? It is arguable that any detectible odor of ether coming from a home constitutes an exigent circumstance because ether is highly volatile.58 For example, in People v. Stegman,59 in which the odor was detected two houses away, the court said, “Ether at such high levels of concentration would be highly dangerous regardless of purpose, thus constituting an exigent circumstance.”
Dead bodies
Officers who respond to a report of a dead body inside a home or other place are not required to assume that the reporting person was able to make a medical determination that the person was deceased. Consequently, they may enter the premises to confirm.60 As the D.C. Circuit observed, “Acting in response to reports of dead bodies, the police may find the ‘bodies’ to be common drunks, diabetics in shock, or distressed cardiac patients. Even the apparently dead are often saved by swift police response.”61
If officers detect the odor of a decaying body coming from the premises, it has been held that if one person is dead under suspicious circumstances, it is not unreasonable for officers to enter to make sure there is no one on the premises who might be saved. Said the Ninth Circuit, “[A] report of a dead body can easily lead officers to believe that someone might be in need of immediate aid.”62 Note that the coroner has a legal right to enter to examine the body and take other action required by law.63
Investigative Threats
Although there is no "crime scene" exception to the warrant requirement, the courts have consistently recognized an exception in situations where there existed an imminent threat that evidence of a crime would be destroyed or corrupted, or that a suspect was, or will soon be, in flight.64
The lawfulness of a search based on such a threat—an “investigative emergency”—is technically determined by employing the same balancing test that is used in the other exigent circumstances; i.e., it is lawful if the need for the action exceeded its intrusiveness. As a practical matter, however, the restrictions on investigative threats are greater because the officers’ objective is to protect a law enforcement interest as opposed to a threat to the general public (although these threats are not necessarily mutually exclusive).
The primary restriction on investigative threats pertains to warrantless entries into homes. In these cases the courts still apply the balancing test, but they generally require that the need portion of the test be supported by probable cause.65 Although. as noted earlier, probable cause is not required when the emergency entry into a home was based on an imminent threat to people or property, most courts consider it an absolute requirement when the only objective is to defuse a threat that is based solely on a law enforcement interest.66 Moreover, the courts are generally not apt to uphold an intrusion based on destruction of evidence or “fresh” pursuit unless the crime under investigation was especially serious.67 (As we will discuss later, the seriousness of the crime is not an important factor when officers are in “hot” pursuit.)
Destruction of evidence
Probably the most common investigative emergency is a threat that certain evidence would be destroyed if officers waited for a warrant.68 This is because a lot of evidence can be destroyed quickly, and its destruction is a top priority for most criminals when they think the police are closing in. There are, however, three requirements that must be met to invoke this exigent circumstance:
EVIDENCE ON PREMISES
Officers must have had probable cause to believe there was destructible evidence on the premises.69 In the absence of direct proof, probable cause may be based on logical inference. For example, people who commit certain crimes (such a drug dealers) usually possess certain instrumentalities or fruits of the crime, and they usually keep these things in their home, car, or other relatively safe place.70
1. JAILABLE CRIME: Although the crime under investigation need not be “serious” or even a felony,71 it must carry a potential jail sentence.72
2. IMPENDING DESTRUCTION: Officers must have been aware of some circumstance that reasonably indicated the suspect or someone else was about to destroy the evidence.73 Thus, the mere possibility of destruction does not constitute an exigent circumstance.74
A common indication that evidence was about to be destroyed is that, upon arrival to execute a search warrant, the officers saw or heard a commotion inside the residence which, based on the their training and experience, was reasonably interpreted as indicating the occupants were destroying evidence or were about to start.75 For example, in People v. Ortiz two officers who were walking past an open door to a hotel room saw a woman “counting out heroin packages and placing them on a table.” The officers then entered without a warrant and court ruled the entry was lawful because:
Viewed objectively, these facts were sufficient to lead a reasonable officer to believe that defendant or the woman saw, or might have seen, the officers. Since it is common knowledge that those who possess drugs often attempt to destroy the evidence when they are observed by law enforcement officers, it was reasonable for [the officer] to believe the contraband he saw in front of defendant and the woman was in imminent danger of being destroyed.76
Some other examples:
• After knocking, the officers “heard noises that sounded like objects being moved.”77
• After the officers knocked and announced, the suspect “disappeared behind the curtains, and the officers heard a shuffling of feet and the sound of people moving quickly about the apartment.”78
• When an occupant opened the door and saw that the callers were officers, he immediately attempted to slam the door shut.79
• After the officers knocked and announced, the suspect opened the door but immediately slammed it shut when she was informed that her accomplice had consented to a search. The officers then “heard footsteps running away from the door, a faucet turn on, and drawers being banged open and closed.” Said the court, “These are classic signs indicating destruction of evidence.”80
• Another “classic” sign is the “repeated flushing of the toilet behind the locked door of the bathroom in premises where [drugs are] being kept and the police are at the threshold.”81
It might also be reasonable to believe that a suspect inside the house would destroy evidence if there was reason to believe that he had just learned, or would quickly learn, that an accomplice or cooccupant had been arrested and would therefore have reason to cooperate with officers.82 As the D.C. Circuit explained, “[T]he police will have an objectively reasonable belief that evidence will be destroyed if they can show they reasonably believed the possessors of the contraband were aware that the police were on their trail.”83
Thus, in People v. Freeny the court concluded that narcotics officers in Los Angeles reasonably believed that the suspect’s wife would destroy drugs in the house because she was inside and her husband had just been arrested some distance away after selling drugs to an undercover officer. Said the court, “No reasonable man could conclude other than that Mrs. Freeny would destroy evidence of her guilt, which was equal to that of appellant, if she learned of his arrest.”84
Note, however, that even if there existed a threat of imminent destruction, a warrantless entry or search will not be upheld if the officers said or did something before entering that they knew, or should have known, would have provided the occupants with a motive to destroy evidence immediately; e.g., an officer without a warrant said “open the door or we’ll break it open.”85 Also, in most cases the evidence can be sufficiently protected by securing the premises while seeking a warrant.
Hot pursuits
In the context of exigent circumstances, a “hot” pursuit occurs when (1) officers had probable cause to arrest the suspect, (2) the arrest was “set in motion” in a public place (which includes the doorway of the arrestee’s home), and (3) the suspect responded by retreating into his home or other private place. When this happens, officers may pursue him inside because, said the Supreme Court, “a suspect may not defeat an arrest which has been set in motion in a public place by the expedient of escaping to a private place.”86
For example, in the case of U.S. v. Santana,87 officers in Philadelphia went to Santana’s house to arrest her because she had just sold drugs to an undercover officer. As they arrived, they saw her standing at the doorway. She saw them too, and ran inside. After they entered and arrested her, the officers seized evidence in plain view which Santana thought should be suppressed. The Supreme Court disagreed, ruling that officers in “hot” pursuit do not need to terminate a chase when the suspect flees into a residence. Some other examples:
• Responding to a report of a domestic dispute, officers found the victim outside her home. Her face and nose were red and she was “crying uncontrollably.” She said her husband, who was inside the house, had “hit her a few times in the face.” The husband opened the door when the officers knocked but, seeing the officers, tried to close it. The officers went in.88
• While staking out a stolen car, an officer saw a known auto burglar walk up to the driver’s side and reach down “as if to open the door.” When the burglar saw the officer, he ran into his home nearby. The officer chased him inside and arrested him.89
• An officer who was investigating a report of a “very strong odor of ether” coming from an apartment, saw Luna step out of the apartment. Luna appeared to be under the influence of PCP. When the officer ordered her to “come down the stairs,” Luna went back into the apartment and closed the door. The officer went in after her.90
• An officer attempted to make a traffic stop on Lloyd who disregarded the officer’s red light and siren, drove home and ran inside. They went inside and arrested him.91
Note that while the other investigative emergencies can be invoked only if the crime under investigation was especially serious, this requirement does not apply to hot pursuits. As the Supreme Court explained, “Where the pursuit into the home was based on an arrest set in motion in a public place, the fact that the offenses justifying the initial detention or arrest were misdemeanors is of no significance in determining the validity of the entry without a warrant.”92
Finally, a suspect who runs from officers triggers the “hot” pursuit exception even though the crime occurred at an earlier time. Thus, the courts have ruled that a hot pursuit “need not be an extended hue and cry in and about the public streets,”93 but it must be “immediate or continuous.”94 For example, in People v. Patino,95 LAPD officers were dispatched late at night to a silent burglary alarm at a bar. As they arrived, they saw a man “backing through the front door carrying a box.” When the man saw the officers, he dropped the box and escaped. About an hour later, the officers saw him again and resumed the chase. When the man ran into an apartment, the officers went in after him and encountered Patino who was eventually arrested for obstruction. Patino contended that the officers’ entry was unlawful, but the court disagreed because “[t]he facts demonstrate that the officers were in hot pursuit of the burglary suspect even though an hour had elapsed after they were first chasing the suspect.”
“Fresh” pursuits
Unlike “hot” pursuits, “fresh” pursuits are not physical chases. Instead, they are pursuits in the sense that officers with probable cause are actively attempting to apprehend the suspect and, in doing so, are quickly responding to developing information as to his whereabouts; and eventually that information adds up to probable cause to believe that he is presently inside his home or other private structure.96 The cases indicate that an entry based on “fresh pursuit” will be permitted if the following circumstances existed:
(1) Serious felony: The crime under investigation must have been a serious felony, usually a violent one.97
(2) Diligence: At all times the officers must have been diligent in their attempt to apprehend the perpetrator.98
(3) Suspect located: The officers must have developed probable cause to believe that the perpetrator was presently inside a certain house or structure.99
(4) Evidence of flight: Officers must have reasonably believed that the perpetrator was in active flight or soon would be.
In some cases, an officer’s belief that a suspect is fleeing will be based on direct evidence. An example is found in People v. Lopez where LAPD officers learned that a murder suspect was staying at a certain motel, and that someone would soon be delivering money to him so that he could escape to Texas.100 In most cases, however, evidence of flight will be based on circumstantial evidence. Examples include seeing a fresh trail of blood leading from a murder scene to the suspect’s house,101 and knowing that a violent parolee-at-large was trying to avoid arrest by staying at different homes.102
In some cases, the fact that the suspect had recently committed a serious felony may also justify the conclusion that he is in active flight. This is because the perpetrator of such a crime will expect an immediate, all-out effort to identify and apprehend him. The length of such an effort will vary depending on the seriousness of the crime and the number of leads. In any event, if during this time officers developed probable cause to believe the perpetrator was inside his home or other place, a warrantless entry will usually be justified under the “fresh” pursuit doctrine. Examples:
• At 8 A.M., Hayden robbed a Baltimore cab company employee at gunpoint. As he left, someone in the office yelled “holdup,” and two cab drivers in the vicinity heard this, saw Hayden, and followed him to his home nearby. Police were alerted, arrived quickly, entered and arrested Hayden. Court: “The police were informed that an armed robbery had taken place, and that the suspect had entered 2111 Cocoa Lane less than five minutes before they reached it. They acted reasonably when they entered the house and began to search for a man of the description they had been given.”103
• The body of a young woman was discovered at 5:20 A.M. along a road in Placer County. She had been raped, robbed, and murdered. Sheriff’s detectives quickly identified the woman and developed probable cause to believe that Williams was the perpetrator. The next day, they found the victim’s stolen car near the apartment of Williams’ girlfriend. They entered the apartment and arrested him. In ruling the arrest was lawful under the “fresh” pursuit doctrine, the court noted that the investigation proceeded steadily and diligently from the time the body was discovered and that “[t]he proximity of the victim’s car clearly suggested defendant’s presence in the apartment, and also made flight a realistic possibility.” 104
• Gilbert killed a police officer in Alhambra during a botched bank robbery. He and one of his accomplices, King, got away but, unknown to them, a third accomplice named Weaver was captured a few minutes later. Weaver identified Gilbert as the shooter and told officers where he lived. While en route to the apartment, officers learned that King had just left the apartment. Figuring that Gilbert was still inside, officers forcibly entered. Although Gilbert was not there, officers found evidence in plain view. During a suppression hearing, one of the officers testified that “we knew . . . there were three robbers. One was wounded and accounted for, one had just left a few minutes before, and there was a third unaccounted for. Presumably he was in the apartment.” The court responded, “Since the officers were in fresh pursuit of two robbers who escaped in the same automobile, [the officer’s] assumption was not unreasonable. The officers entered, not to make a general exploratory search to find evidence of guilt, but in fresh pursuit to search for a suspect and make an arrest. A police officer had been shot, one suspect was escaping, and another suspect was likely to escape.”105
Community Caretaking
As noted earlier, the role of law enforcement officers in the community has grown over the years. In fact, it now includes an “infinite variety of services,”106 that are “totally divorced from the detection, investigation, or acquisition of evidence relating to the violation of a criminal statute.”107 Sometimes the responding officers determine that they cannot resolve the matter unless they enter or maybe even search a home, business, or car. Can they do so without a warrant?
In the past, the answer was usually no because there was no demonstrable threat to life or property.108 But as time went on, cases started cropping up in which the courts would acknowledge that, despite the absence of a true emergency, they could not fault the officers for intervening. Some of these courts avoided issue by invoking the “harmless error” or “inevitable discovery” rules, or saying that a true emergency existed even though it obviously didn’t. Others would rule that the search was illegal and that the evidence must be suppressed but, at the same time, they would say something like, “I don’t think that the officers were wrong in what they did. In fact, I commend them.”
Over time, however, the courts started confronting the issue. One of the first to do so was the California Supreme Court which, in People v. Ray, pointed out many people nowadays “do not know the names of [their] next-door neighbors” and that “tasks that neighbors, friends or relatives may have performed in the past now fall to the police.” And, said the court, there would be “seriously undesirable consequences for society at large” if officers were required to explain to the reporting person, “Sorry. We can’t help you. We need a warrant but can’t get one because there’s no ‘crime.’”109
This is why the courts now recognize the relatively new exigent circumstance that has become known as “community caretaking” or “special needs.”110 Examples of typical community caretaking situations include “check the welfare calls,” clearing vehicle accidents, looking for lost children and, recently, trying to corral a loose horse.111
CARETAKING VS. EXIGENT CIRCUMSTANCES
Although some courts have suggested that community caretaking and exigent circumstances are separate concepts, they are not. On the contrary, they are both (1) based on a situational and readily-apparent need that can only be met, or is traditionally met, by law enforcement officers; and (2) are subject to the same balancing test: the police action is lawful if the need for it outweighed its intrusiveness.
There are, however, three significant differences between community caretaking and exigent circumstances. First, community caretaking situations are, by definition, not as dangerous as traditional exigent circumstances.112 This means that searches and seizures based on community caretaking will ordinarily be upheld only if the officers’ response was relatively nonintrusive. Second, an intrusion based on a community caretaking interest may be deemed unlawful if the court finds that the officers’ sole motivation was to make an arrest or obtain evidence.113 As the California Supreme Court explained, “[C]ourts must be especially vigilant in guarding against subterfuge, that is, a false reliance upon the personal safety or property protection rationale when the real purpose was to seek out evidence of crime.”114
Third, unlike police actions that are based on exigent circumstances, officers are not expected to respond to every situation that could be justified by a community caretaking interest. As the New York Court of Appeals explained:
[W]e neither want nor authorize police to seize people or premises to remedy what might be characterized as minor irritants. People sometimes create cooking odors or make noise to the point where neighbors complain. But as we live in a free society, we do not expect the police to react to such relatively minor complaints by breaking down the door.115
Still, it may happen occasionally that the officers cannot just ignore the problem just because it might be classified as a “minor irritant.” For example, in U.S. v. Rohrig 116 officers responded to a report of loud music coming from Rohrig’s house. The time was 1:30 A.M., and the music was so loud that the officers could hear it about a block away. As they pulled up, several “pajama-clad neighbors emerged from their homes to complain about the noise.” The officers knocked on Rohrig’s door and “hollered to announce their presence” but no one responded. Having no apparent alternatives (other than leaving the neighbors at the mercy of Rohrig’s thunderous speakers), the officers entered the house through an unlocked door and saw wall-to-wall marijuana plants. Not only did the court rule that the officers’ response was appropriate, it noted the absurdity of prohibiting them from assisting the neighbors:
[I]f we insist on holding to the warrant requirement under these circumstances, we in effect tell Defendant’s neighbors that “mere” loud and disruptive noise in the middle of the night does not pose “enough” of an emergency to warrant an immediate response, perhaps because such a situation ‘only’ threatens the neighbors’ tranquility rather than their lives or property. We doubt that this result would comport with the neighbors’ understanding of “reasonableness.”
Intrusiveness of Response
So far we have been discussing how the courts determine the strength of the need to enter a residence or take other action in response to an exigent circumstance. Now, having determined the importance of taking action, the courts must weigh this circumstance against the intrusiveness of the officers’ actions. And if the need was equal to or greater than the intrusiveness, the police response will be deemed lawful. Otherwise, it won’t.
But, in addition to the abstract intrusiveness of the officers’ response (or sometimes in place of it), the courts will focus more on whether the officers responded to the threat in a reasonable manner,117 which essentially means that their response displayed a “sense of proportion.” 118
Officers are not, however, required to utilize the least intrusive means of defusing the emergency. As the Supreme Court explained, “The question is not simply whether some other alternative was available, but whether the police acted unreasonably in failing to recognize or to pursue it.”119 Furthermore, the courts have been cautioned to avoid second-guessing the officers’ assessment of the need for immediate action so long as it was within the bounds of reasonableness. Thus, the California Court of Appeal observed, “Of course, from the security of our lofty perspective, and despite our total lack of practical experience in the field, we might question whether or not those who physically confronted the danger in this instance, selected the ‘best’ course of action available.”120
Although it is not possible to rank the various police responses on an intrusiveness scale, there are some generalizations that can be made.
ENTERING A HOME: The most intrusive of the usual police responses to exigent circumstances is a forcible entry into a home. As the Supreme Court observed, “[P]hysical entry of the home is the chief evil against which the wording of the Fourth Amendment is directed.”121 For this reason (as discussed earlier) the courts have consistently ruled that such an intrusive response can be justified only if the officers had probable cause to believe the threat would materialize.
Also note that, in addition to the physical entry, the courts will consider whether the officers gave notice of their identity and purpose beforehand. Again quoting the Supreme Court, “[T]he method of an officer’s entry into a dwelling [is] among the factors to be considered.”122
AFTER ENTRY: While a full search is permitted if it was reasonably necessary,123 it is seldom necessary because most threats can be defused by conducting a “sweep” or “walk-through” to either locate a fleeing suspect or determine if there is anyone inside who needs help or who might destroy evidence. Then, if necessary, officers can secure the premises pending issuance of a warrant, whether by removing the occupants or preventing anyone from entering. For example, in Segura v. United States the Supreme Court pointed out that “[i]n this case, the agents entered and secured the apartment from within. Arguably, the wiser course would have been to depart immediately and secure the premises from the outside by a ‘stakeout’ once the security check revealed that no one other than those taken into custody were in the apartment. But the method actually employed does not require a different result.”124
TRESPASSING: Merely walking on a suspect’s property may constitute a technical search, but it is relatively nonintrusive, and will be deemed reasonable if the officers’ entry was restricted to areas that needed to be checked in order to defuse the threat.125 If there was reason to believe that an emergency existed inside a home, an officer’s act of looking through windows from outside is also considered nonintrusive.126
MAKE SAFE: If the emergency resulted from a dangerous condition (e.g., a meth lab), officers may do those things that are reasonably necessary to eliminate the threat, including a search. As the Fourth Circuit observed, “The authority to defuse a threat in an emergency necessarily includes the authority to conduct searches aimed at uncovering the threat’s scope.”127
SEARCHING CELL PHONES: Officers may access the contents of a cell phone without a warrant if they reasonably believed that immediate access was necessary to defuse an imminent danger of death or serious physical injury.128 Otherwise, officers must seize the phone to protect it and its contents from destruction, then seek a warrant.129
Vacating and Reentry
Officers who have entered a home or business pursuant to exigent circumstances must leave within a reasonable amount of time after the threat to people, property, or evidence has been eliminated. As noted, however, they may secure the premises (i.e., temporarily “seize” it) pending the issuance of a search warrant if they reasonably believed they had probable cause for one.130 Thus, officers must avoid what happened in the landmark case of Mincey v. Arizona.131
Here, an officer in Tucson was killed by a drug dealer when officers entered the suspect’s apartment to execute a search warrant. After the premises were secured, officers supervised the removal of the officer’s body and made sure that “the scene was disturbed as little as possible.” These actions were plainly permissible. But then the officers “proceeded to gather evidence.” In fact, they remained in the home for four days, during which time they “opened drawers, closets, and cupboards, and inspected their contents; they emptied clothing pockets; they dug bullet fragments out of the walls and floors; they pulled up sections of the carpet and removed them for examination.” All told, they seized between 200 and 300 items.
In the Supreme Court, the government urged the Court to establish a “crime scene exception” to the warrant requirement or, at least, a “murder scene” exception. The Court refused. Although it acknowledged that the crime under investigation was exceptionally serious, and although the officers had probable cause for a warrant that could have authorized an intensive search, it ruled that “the warrantless search of Mincey’s apartment was not constitutionally permissible simply because a homicide had recently occurred there.”
When to vacate
Like most things involving exigent circumstances, there is no simple test to determine the point at which officers must stop and obtain court authorization for any further intrusion. So we will simply review a few examples of situations in which the courts addressed the issue.
EXPLOSIVES: The emergency created by the presence of explosives in a structure ended when the danger has been eliminated.132
DANGEROUS CHEMICALS: The emergency ended when the imminent danger of fire or explosion has been eliminated.133
STRUCTURE FIRES: The exigency caused by a residential or commercial structure fire does not automatically end when the fire is under control or even with the “dousing of the last flame.”430 Instead, it ends after investigators have determined the cause and origin of the fire,135 and have determined that the premises were safe for re-occupancy.136 The amount of time that is reasonably necessary for such purposes will depend on the size of the structure; conditions that made the investigation more time-consuming, such as heavy smoke and poor lighting; and whether there were other circumstances that delayed the investigation, such as the presence of explosives or dangerous chemicals.137 Still, a warrant will be required when investigators have concluded that the cause was arson and their purpose had shifted from finding the cause and origin to conducting a criminal investigation.138
SHOOTING INSIDE A RESIDENCE: The emergency created by a murder or non-fatal shooting in a residence ends after officers had determined there were no suspects or other victims on the scene, the victim had been removed, and there was no threat to evidence located inside.139
BARRICADED SUSPECT: The threat ends after the suspect was arrested and officers determined there were no victims or other suspects inside.140
BURGLARY IN PROGRESS: The emergency ends after officers arrested the burglar and had determined there were no accomplices on the premises, and that the residents were not in need of emergency aid.141
Reentry
After vacating the premises, officers may not reenter unless they have a search warrant or consent.142 Exception: Officers may reenter for the limited purpose of seizing evidence if (1) they saw the evidence in plain view while they were lawfully inside; (2) due to exigent circumstances, it was impractical to seize the evidence before the emergency was neutralized; and (3) the officers had not surrendered their control of the premises.143
For example, in People v. Superior Court (Quinn) 144 an officer entered a house on grounds of hot pursuit. While looking for the suspect, he saw drugs which he did not seize because the suspect was still at large. Immediately after arresting the suspect and removing him from the premises, the officer reentered the residence and retrieved the drugs. Although the emergency was over when the officer reentered, the court ruled the reentry was lawful because the officer “did not trench upon any constitutionally protected interest by returning for the single purpose of retrieving contraband he had observed moments before in the bedroom but had not then been in a position to seize.”
Similarly, in Cleaver v. Superior Court two men shot two officers in Oakland then, after a shootout, barricaded themselves in the basement of a home. About two hours later, officers launched a tear gas canister into the building, causing a fire.145 One of the suspects was shot and killed as he fled; the other, Cleaver, was arrested. Evidence technicians were initially unable to enter the basement because of smoke and tear gas. But about three hours later one of them entered and seized some evidence but could not conduct a thorough search because of impaired visibility. About six hours later, an officer entered and recovered additional evidence.
In upholding both reentries, the California Supreme Court said, “The 11:30 P.M. search was thwarted by residual smoke, fumes and tear gas. The relatively short delays until 2 A.M. and 8 A.M. necessitated by darkness and continuing impaired visibility, cannot be deemed constitutionally improper or unreasonable under all the circumstances yet in this case.” | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/12%3A_Exigency_and_Community_Caretaking/12.1%3A_Exigent_Circumstances.txt |
Special law enforcement concerns will sometimes justify detentions without reasonable suspicion. —Illinois v. Lidster 1
For years and years, every police interaction with the citizenry was classified by the courts as a contact, an investigative detention, or an arrest. Over time, however, a fourth category started to appear in the cases—and today it has become firmly established in the law. Commonly known as a “special needs” or “community caretaking” detention, it is defined as a temporary seizure of a person that serves a public interest other than the need to determine if the detainee had committed a crime or was committing one.
Why was a new type of detention necessary? It was because the role of law enforcement officers in the community has expanded over the years to include an “infinite variety of services”2 that are “totally divorced” from the apprehension of criminals.”3 As the First Circuit observed in U.S. v. Rodriguez-Morales, officers are now expected to “aid those in distress, combat actual hazards, [and] prevent potential hazards from materializing.”4
As the result of these new demands, it is sometimes necessary for officers to stop and speak with people who are not suspected of criminal activity. This creates a problem: When an officer signals or otherwise instructs a person to stop, that person is automatically “detained.”5 And, under the old law, it would be an illegal detention because officers were only allowed to detain suspected criminals; i.e., the officers must have had reasonable suspicion. So, they would often find themselves in a classic Catch-22 situation: the public interest would be served if they detained the person; but if they did so, they would be breaking the law. Commenting on this dilemma, the Supreme Judicial Court of Maine said:
If we were to insist upon suspicion of activity amounting to a criminal or civil infraction to meet the [detention] standard, we would be overlooking the police officer’s legitimate role as a public servant to assist those in distress and to maintain and foster public safety.6
And that, in a nutshell, is why special needs detentions are now recognized by the courts. But this recognition came slowly. There were no “major” cases or public outcry over death or destruction resulting from the inability of officers to make special detentions.7 Instead, it happened slowly as state appellate courts and the federal circuits were called upon more and more to address these situations. As the California Court of Appeal observed in 2008, “Though no published California case has specifically addressed this question, a number of other states recognize that a police officer may utilize the community caretaking exception to justify the stop.”8
But without a groundbreaking case, there have been no authoritative decisions setting forth the precise requirements for detaining people under the many and varied circumstances that constitute special needs. Nevertheless, as we will discuss in this article, the number of published cases on this issue has reached the point that most of the uncertainty has been eliminated.
When Permitted
There is general agreement that officers may conduct special needs detentions if both of the following circumstances existed:
1. Public interest: The primary purpose of the detention must have been to further a public interest other than determining whether the detainee had committed a crime.9 The most common public interests that fall into this category are checking welfare or otherwise preventing harm, locating witnesses to a crime, securing the scene of police activity, and conducting noncriminal detentions on school grounds.
2. Public interest outweighed intrusiveness: This public interest must have outweighed the intrusiveness of the detention.
As the U.S. Supreme Court explained, “[I]n judging reasonableness, we look to the gravity of the public concerns served by the seizure, the degree to which the seizure advances the public interest, and the severity of the interference with individual liberty.”10
Public interests vs. law enforcement interests While all lawful detentions serve the public interest, the courts sometimes say that special needs detentions are permitted only if their primary purpose was “totally divorced from the detection, investigation, or acquisition of evidence relating to the violation of a criminal statute.”11 To put it another way, the objective must have been something other than a “general interest in crime control.”12
Yet, this concept can be confusing because many of the special needs that result in detentions are linked indirectly—and sometimes directly—to criminal activity. As the Supreme Court of Connecticut observed, “Police often operate in the gray area between their community caretaking function and their function as criminal investigators.”13
Fortunately, much of the confusion surrounding the terms “totally divorced” and “general interest in crime control” was eliminated by the Supreme Court in its most recent case on the subject, Illinois v. Lidster.14 Specifically, the Court ruled that this language simply means that a detention will not be upheld under a special needs theory if the officers’ primary objective was to determine if there were grounds to arrest the detainee.
The facts in Lidster are illustrative. Officers in Lombard, Illinois had been unable to locate the hitand-run driver of a car that had struck and killed a bicyclist. So, one week after the accident, they set up a checkpoint near the scene and asked each passing motorist if he had seen anything that might help identify the perpetrator. Lidster was one of the drivers who was stopped, and he was arrested after officers determined that he was under the influence of alcohol. Lidster argued that the detention was unlawful because its purpose was to apprehend the hit-and-run driver. While that was its ultimate purpose, said the court, it met the requirement for a special needs detention because its immediate objective was “to ask vehicle occupants, as members of the public, for their help in providing information about a crime in all likelihood committed by others.”
Another objective that often falls into the gray area between special needs and crime control is public safety. Thus, while one of the objectives of DUI checkpoints is to arrest impaired motorists, these checkpoints fall into the category of special interest detentions because their co-objective is to reduce the death and destruction that results from drunk driving.15
An additional public safety interest that sometimes touches on crime control is the stopping of cars that are being operated in an unusual manner, but not so unusual or erratic as to be “worthy of a citation.”16 For example, in People v. Bellomo 17 an LAPD motorcycle officer noticed that the driver of a car stopped at a red light had his head “resting on the window” and his eyes “appeared to be closed.” The officer stopped the car because he thought it was “very strange for the driver of the vehicle to be in this condition in a moving lane of traffic,” and because he was concerned there was “something physically or mentally wrong” with him. It turned out the driver, Bellomo, was under the influence of alcohol, and he argued that the detention was unlawful because the officer saw nothing to indicate that he was impaired or citable. Even so, said the court, the detention was warranted because the officer’s conduct was “reasonably consistent with his overall duties of protecting life and property and aiding the public.”
In contrast, officers in Indianapolis v. Edmond established a drug-interdiction checkpoint in which they would walk a drug-detecting dog around each car in the line. Thus, unlike the situation in Lidster, the purpose of the checkpoint in Edmond was, in fact, to determine if the occupants were committing a crime. Edmond sued the city, arguing that the checkpoint resulted in an unlawful detention, and the United States Supreme Court agreed. Said the Court, “Because the primary purpose of the Indianapolis narcotics checkpoint program is to uncover evidence of ordinary criminal wrongdoing, the program contravenes the Fourth Amendment.”18
Similarly, in State v. Hayes 19 officers in Chattanooga set up a roadblock outside a high-crime housing project for the purpose of “excluding trespassers.” Although one of its objectives was “to help [the residents’] quality of life issues,” the court ruled it did not qualify as a special needs detention because its immediate objective was to identify and exclude those vehicle occupants who were believed to be causing problems.
Weight of the public interest
As noted, even if the primary purpose of the detention was to further a public interest other than general crime control, it will not be permitted unless the need for the detention outweighed its intrusiveness.20 Consequently, it is necessary to determine the weight of the public interest that was served by taking into account the following: (1) its importance to the public, (2) the likelihood that the detention would effectively serve that public interest, and (3) whether there were any less intrusive alternatives that were readily available.
IMPORTANCE OF THE PUBLIC INTEREST: Although a special needs detention is much less intrusive than an arrest or search, it will not be upheld unless is serves a sufficiently important public interest.21 As the Washington Supreme Court explained, “We must cautiously apply the community caretaking function exception because of a real risk of abuse in allowing even well-intentioned stops to assist.”22 Or, as the court put it in People v. Molnar, “[W]e neither want not authorize police to seize people or premises to remedy what might be characterized as minor irritants.”23 For example, in U.S. v. Dunbar, where an officer stopped a motorist because he appeared lost, the court pointed out that the “policy of the Fourth Amendment is to minimize governmental confrontations with the individual”; but that policy is not served if the courts permit officers to detain people “simply for the well-intentioned purpose of providing directions.”24
On the other hand, the California Court of Appeal explained that, while officers are not permitted to “go around promiscuously bothering citizens,” they may take actions that are “reasonably consistent” with their “overall duties of protecting life and property and aiding the public in maintaining lives of relative serenity and tranquility.”25 For example, the Supreme Court in Michigan State Police v. Sitz upheld a DUI checkpoint because of, among other things, the “magnitude of the drunken driving problem,” and the “State’s interest in preventing drunken driving.”26 Similarly, in determining the need for the detentions of possible witnesses in Lidster (the felony hit-and-run case discussed earlier) the Court pointed out that “[t]he relevant public concern was grave. Police were investigating a crime that had resulted in a human death.”27 (Several other examples of significant public interests will be discussed later.)
PROOF OF EFFECTIVENESS: The strength of the need to detain will also depend on the likelihood that the detention would effectively serve that need; i.e., that it will be “a sufficiently productive mechanism” to justify the intrusion.28 For example, in Delaware v. Prouse the Supreme Court invalidated a departmental practice in which officers would make random car stops to determine whether the drivers were properly licensed. Said the Court, it was apparent that “the percentage of all drivers on the road who are driving without a license is very small and that the number of licensed drivers who will be stopped in order to find one unlicensed operator will be large indeed.”29
In contrast, the Court in Lidster pointed out that there was reason to believe the checkpoint to locate witnesses would be effective because it “took place about one week after the hit-and-run accident, on the same highway near the location of the accident, and at about the same time of night.”30
ALTERNATIVES? Finally, the need to detain a person would necessarily be greater if there were no less intrusive alternatives that were readily available. For example, in People v. Spencer 31 officers stopped a car because the driver was a friend of the suspect in a day-old assault, and the officer wanted to determine if he knew the suspect’s whereabouts. But the court ruled there was insufficient need for the detention because the officers knew the detainee’s name and they could have contacted him at home. Said the court, “[T]here was no genuine need for so immediate and intrusive an action as pulling over defendant’s freely moving vehicle.” In contrast, the court in U.S. v. Ward ruled that a car stop of a potential witness by FBI agents was lawful because, although the agents knew the witness’s name and address, they could not question him at his home because his roommates were suspected fugitives.32
Note that the mere existence of a less intrusive alternative will not invalidate a detention unless the officers were negligent in failing to recognize and implement it.33 As the Supreme Court put it, “The question is not simply whether some other alternative was available, but whether the police acted unreasonably in failing to recognize or to pursue it.”34
Intrusiveness of the Detention
Until now, we have been discussing only one half of the balancing equation: the strength of the need for the detention. But, as noted, the legality of a special needs detention depends on whether this need outweighed the intrusiveness of the stop. “[T]he manner in which the seizure was conducted,” said the Supreme Court, “is as vital a part of the inquiry as whether it was warranted at all.”35
How do the courts assess a detention’s intrusiveness? The most cited circumstances are, (1) the manner in which the detainee was stopped, (2) whether officers utilized officer-safety precautions, (3) the length of the detention, and (4) whether it was conducted in a place and in a manner that would have caused embarrassment or unusual anxiety.
Although the above circumstances are relevant, in most cases a special needs detention is not apt to be viewed as excessively intrusive if, (1) it was brief, and (2) officers did only those things that were reasonably necessary to accomplish their objective. That is because brief and efficient detentions are viewed by the courts as “modest” or “minimal” intrusions. Thus, in ruling that special needs detentions were relatively nonintrusive, the courts have noted:
• “Such a stop entailed only a brief detention, requiring no more than a response to a question or two and possible production of a document.”36
• The detention was “minimally” intrusive as it lasted “a very few minutes at most.”37
• “Several circumstances diminish the intrusiveness of the initial detention here. First and foremost, it was extremely brief.” 38
• “[T]he restraint at issue was tailored to that need, being limited in time and scope.”39
• Traffic stop was only a “minor annoyance.”40
• The officer “did no more than was reasonably necessary to determine whether [the detainee] was in need of assistance.”41
• “At a minimum, officers had a right to identify witnesses to the shooting, to obtain the names and addresses of such witnesses, and to ascertain whether they were willing to speak voluntarily with the officers.”42
As for roadblocks and checkpoints, they too will usually be considered only a minor intrusion if, (1) they were brief, (2) all vehicles were stopped (i.e., vehicles were not singled out), and (3) it would have been apparent to the motorists that the stop was being conducted by law enforcement officers.43
Having examined the procedure for determining whether a special needs detention was justified, we will now look at the most common special needs cited by officers, and how the courts have analyzed them.
Types of Special Needs Detentions
There are essentially four types of special needs detentions that have been recognized to date: community caretaking detentions, stops to locate witnesses to a crime, securing the scene of police activity, and noncriminal detentions on school grounds.
Community caretaking detentions
Of all the circumstances that may warrant a special needs detention, the most urgent is an officer’s reasonable belief that the detainee was in imminent danger or was otherwise in need of immediate assistance. Thus, in discussing these types of stops— commonly known as “community caretaking detentions”44—the Montana Supreme Court pointed out that “the majority of the jurisdictions that have adopted the community caretaker doctrine have determined that a peace officer has a duty to investigate situations in which a citizen may be in peril or need some type of assistance from an officer.”45
The following are the most common justifications that are cited for community caretaking detentions.
SICK OR INJURED PERSON
Whether officers may detain a person whom they believe may be sick or injured will generally depend on “the nature and level of distress exhibited.”46 The following are examples of circumstances that have been found to generate a strong need:
• The victim of an assault had just left the crime scene in the car; officers stopped the vehicle because the crime was “potentially serious” and “the victim, with knowledge of the incident and possibly in need of medical attention, had just left the scene.47
• An officer detained a man who was sitting in a vehicle that was parked at the side of a roadway at 3 A.M.; the headlights were off but the motor was running. Although the man appeared to be asleep, the court pointed out that “he might just as likely have been ill and unconscious and in need of help.”48
• The driver of a car that was stopped at a traffic light was leaning his head against the window, and his eyes “appeared to be closed. Said the court, “The operation of a motor vehicle by a driver disabled for any reason be it a disability that is statutorily prohibited or not, is manifestly a serious event and the need for swift action is clear beyond cavil.”49
• At 3 A.M., the driver of a car “stopped or slowed considerably five times within approximately 90 seconds” and then pulled off the road. The court ruled that “it was reasonable for the officer to conclude, among other things, that “something was wrong” with the driver or his vehicle.50
• Responding to a report that a man in a field was “unconscious in a half-sitting, half-slumpedover position,” officers found him on the ground and detained him so that fire department personnel could examine him.51
In contrast, the California Court of Appeal in People v. Madrid ruled that a community caretaking detention was unwarranted because the detainee was merely “walking with an unsteady gait and sweating” and “stumbled.” Such symptoms, said the court, demonstrated “a low level of distress.”52
MISSING PERSON: Another significant circumstance is that the detainee had been reported missing. Thus, in State v. Diloreto, the New Jersey Supreme Court ruled that a car stop was warranted because, per NCIC, a possible occupant of the vehicle was an “endangered missing person.”53
MENTAL HEALTH ISSUES: A detention may be warranted if it appeared that the detainee was so mentally unstable as to constitute a threat to himself or others. Some examples:
• Detainee “was possibly intoxicated and was observed exiting and reentering a vehicle that was parked on a dead-end street.”54
• Detainee was walking down the street at 1 A.M. “crying and talking really loudly or shouting,” “his hands were over his face.”55
• Detainee had reportedly taken “some pills,” he was “agitated” and “physically aggressive” and he “did not know where he was.”56
• Before driving off in a car, the detainee went “ballistic,” screaming and banging her head on the car.57
WARN OF DANGER: Officers may detain a person to notify him of a dangerous condition or prevent him from entering a dangerous place.58 For example, in People v. Ellis the California Court of Appeal ruled that an officer properly stopped a car at 2 A.M. in a parking lot to warn the driver that his lights were off. Said the court, the officer was “not required to wait until appellant actually drove upon a public street to stop appellant.”59
Similarly, in State v. Moore a park ranger signaled the defendant to stop because, although he was not speeding, he was driving too fast for conditions; i.e., pedestrians in the campground did not have a clear view of approaching cars because of parked vehicles. Said the court, “Although defendant makes a plausible argument that his driving did not constitute a criminal violation, the park ranger nevertheless could have reasonably concluded that it posed a threat to the safety of other persons in the park.”60
Finally, in In re Kelsey C.R.61 officers in Milwaukee were patrolling a high-crime neighborhood at about 7:40 P.M. when they saw a 17-year old girl who was leaning against a storefront in a “huddled position.” Thinking that she might be a runaway, the officers detained her and subsequently discovered she was armed with a handgun. On appeal, the Supreme Court of Wisconsin ruled that these circumstances constituted sufficient reason to detain her, pointing out, among other things, that “something bad could have happened” to her if the officers had not intervened; and that a minor “alone in a dangerous neighborhood is vulnerable to kidnappers, sexual predators, and other criminals.”
Locate witnesses
The need to locate or identify witnesses to a crime may also constitute a special need, especially if the crime was serious and if it had just occurred. The theory here is that, while many witnesses will voluntarily come forward and tell officers what they saw, some will not because they are hesitant about becoming involved or because they don’t realize they saw or heard something significant. This can create a problem for officers at the crime scene because the only way to determine whether someone was a witness is to talk to him; and if he is leaving, they must either let him go (and lose whatever information he might have) or detain him.
While some courts ruled in the past that detentions for such an objective are not permitted,62 the U.S. Supreme Court rejected this view in 2004. The case was Illinois v. Lidster 63 (the felony hit-and-run case discussed on page two) and the Court ruled that, like other special needs detentions, detentions for the purpose of locating and identifying witnesses are lawful if the need to find a witness outweighed the intrusiveness of the stop. As the Court observed, it would seem “anomalous” if the law allowed officers “to seek the voluntary cooperation of pedestrians but ordinarily to forbid police to seek similar voluntary cooperation from motorists.”
Before we discuss how officers can determine whether a need to locate witnesses is sufficiently strong, it should be noted that in many cases the circumstances that would justify a detention of a person as a potential witness would also warrant a detention of that person to determine if he was the perpetrator. This is especially true if officers arrived shortly after the crime occurred or if there was some other reason to believe that the perpetrator was still on or near the scene. Thus, in one such case, the D.C. Circuit ruled that officers who had just arrived at the scene of a shooting were “not required to sort out appellant’s exact role—participant or witness—before stopping him to inquire about a just-completed crime of violence.”64
SERIOUSNESS OF THE CRIME: The most important circumstance is, of course, the seriousness of the crime that the detainee might have witnessed. In most cases, these types of detentions will be upheld only when the crime was especially serious, usually a felony and oftentimes one that resulted in an injury or an imminent threat to life or property.65
LIKELIHOOD THE DETAINEE WITNESSED THE CRIME:
The need for a detention will also depend on the likelihood that the detainee had, in fact, witnessed the crime. While officers must, at a minimum, have reasonable suspicion,66 their belief that the detainee was a witness may be based on direct evidence or reasonable inference. An example of direct evidence is found in Williamson v. U.S.67 in which two officers on patrol in Washington D.C. heard several gun shots nearby at about 3:45 A.M. As they looked in the direction of the shots, they saw one car speeding off and some people starting to get into a second car in a “very quick hurry.” The officers stopped the second car because, as one of them testified, he was unsure whether the occupants were the shooters or the targets of the shooting. In the course of the stop, one of the occupants was arrested for carrying an unregistered firearm. On appeal, he contended that the gun should have been suppressed because the officers lacked grounds to stop the car. But the court disagreed, pointing out that the officers had first-hand knowledge that the occupants of the second car “were either participants in the shooting or witnesses to it who could provide material information about the event and the possible identity of the shooter.”
An officer’s belief that a person was a witness to a crime may also be based on circumstantial evidence, such as the following: (1) the crime had just occurred, (2) the perpetrator fled toward a certain area, (3) the detainee was the only person in that area or one of only a few, and (4) it was likely that anyone in the area would have seen the perpetrator. It may also be reasonable to believe that a person was a witness if the crime had just occurred and he was one of few people at the scene when officers arrived. As the Minnesota Supreme Court observed, “Our court, as well as courts of other states, have recognized that in order to ‘freeze’ the situation, the stop of a person present at the scene of a recently committed crime of violence may be permissible.”68
IMPORTANCE OF INFORMATION: Even if officers had good reason to believe that the detainee was a witness, the legality of the detention will depend on whether they reasonably believed that he would be able to provide important information. It seems apparent, however, that anyone who was reasonably believed to have been a witness to all or part of the crime would qualify because he could be expected to, among other things, identify or describe the perpetrator, describe the perpetrator’s vehicle, explain what the perpetrator said or did, explain what the victim said or did, recount how the crime occurred, eliminate another suspect as the perpetrator, lead officers to physical evidence, or provide officers with the names of other witnesses.
For example, in Wold v. Minnesota,69 officers in Duluth were dispatched at about 11 P.M. to a stabbing that had just occurred on a street. When they arrived, they noticed that two men were shouting at the paramedics who were treating the unconscious victim. So the officers detained the men and, as things progressed, determined that one of them, Wold, was the assailant. On appeal, the court ruled that the officers had good reason to detain the men because, as the only people on the scene (other than the victim), they might have seen what had happened. Said the court, “[W]e cannot fault [the officers’] conclusion that both of the individuals may have witnessed the crime, or that either or both might be potential suspects involved in the commission of this violent assault.”
Similarly, in Barnhard v. State,70 police officers in Maryland were dispatched to a report of a stabbing at Bubba Louie’s Bar. One of the patrons, Barnhard, told them that he knew where the knife had been discarded. But then he became uncooperative and started to leave. So the officers detained him, apparently for the purpose of learning where the knife was located. But Barnhard fought the officers and was charged with, among other things, battery on an officer in the performance of his duties. Barnhard claimed that the officers were not acting in the performance of their duties because they did not have grounds to believe he was the perpetrator. It didn’t matter, said the court, because Barnhard had indicated that he possessed “material information” pertaining to the stabbing.
It appears that a person who was not an eyewitness to the crime might, nevertheless, be detained if officers reasonably believed he had seen the perpetrator or his car. For example, in Baxter v. State,71 two men armed with handguns and wearing Halloween masks robbed a jewelry store in Little Rock at about 4 P.M. Witnesses reported that the men ran out the back door. One of the responding officers was aware that the back door of the jewelry store led to a wooded area that adjoined Kanis Park. So he headed for the park and, just as he arrived, he saw a man in a car traveling in the direction away from the jewelry store. The officer decided to stop the car to determine if the driver “had seen anybody.” It turned that out he had. In fact, he was the getaway driver and the two robbers were found hiding in the back seat. In ruling that the stop was justified by the need to locate a witness, the court pointed out that “[t]he time sequence was such that a person in Kanis Park about the time that appellant was stopped likely would have seen the robbers—there being no one else in the park on this rainy afternoon.”
In a similar case, Beauvois v. State,72 a man armed with a knife robbed a 7-Eleven store in Fairbanks, Alaska at about 2:50 A.M. He was last seen on foot and, according to witnesses, he was running in the direction of a campground. Within a minute of receiving the call, an officer arrived at the only entrance to the campground, intending to “stop any moving vehicle” on the theory that, while “most people would be sleeping at 3 A.M., anyone who was awake might have seen something.” The first car he saw was a Corvette occupied by two men, so he stopped it and discovered that one of the men was the robber. In ruling that the detention was lawful, the court said:
It was reasonable to suspect that the occupants of the Corvette had been awake in the campground when the robber came through, and that they might have seen something. Under these circumstances, and especially given the recency and the seriousness of the crime, prompt investigative efforts were justified.
Securing the scene of police activity
Officers who are conducting a search, making an arrest, or processing a crime scene may, of course, take “unquestioned police command” of the location.
As the Supreme Court observed, “[A] police officer at the scene of a crime, arrest, or investigation will not let people move around in ways that could jeopardize his safety.”73 Similarly, the Eleventh Circuit noted that “a police officer performing his lawful duties may direct and control—to some extent—the movements and location of persons nearby.”74
But because a command to such a person will necessarily result in a detention (since a reasonable person in such a situation would not feel free “to decline the officer’s requests” 75) it falls into the category of a special needs detention. The following are the most common situations in which these types of detentions occur:
CAR STOPS: When officers make a car stop, they will usually have grounds to detain the driver and sometimes one or more of the passengers. But what about passengers for whom reasonable suspicion does not exist?
In the past, this was problematic because, in the absence of reasonable suspicion, officers could not lawfully command a non-suspect occupant to do anything without converting the encounter into an illegal detention. In 2007, however, the United States Supreme Court ruled in Brendlin v. California that, because of the overriding need of officers to exercise control over all of the occupants, any non-suspect passengers will be deemed detained under what is essentially a special needs theory.76
HIGH-RISK RESIDENTIAL SEARCHES: Because of the increased danger associated with the execution of warrants to search private residences for drugs, illegal weapons, or other contraband, the Supreme Court ruled that officers may detain all residents and other occupants pending completion of the search.77 Officers may also briefly detain people who arrive outside the residence while officers are on the scene if the person’s identity and connection to the premises are unknown and cannot be immediately determined without detaining him.78 The purpose of these types of detentions is to ascertain whether the person is a detainable occupant or merely an uninvolved visitor.
EXECUTING ARREST WARRANTS: Officers who have entered a home to execute an arrest warrant, like officers who have made a car stop, need to exercise unquestioned control over all of the occupants. Consequently, they may detain people who are inside when they arrive, or who are about to enter.79
SEARCHES AND ARRESTS IN PUBLIC PLACES: Officers who are searching a business or other place that is open to the public may detain a person on or near the premises only if there was reasonable suspicion to believe that that person was connected to the illegal activities under investigation.80 In other words, a special needs detention will not be permitted merely because the detainee was present in a public place in which criminal activity was occurring. Officers may, however, prevent people from entering a public place that is about to be searched pursuant to a warrant.81
PAROLE AND PROBATION SEARCHES: A brief detention of people leaving the home of a probationer has been deemed a special need when officers, who had arrived to conduct a probation search, detained them to determine if they were felons. This information was relevant in determining whether the probationer was associating with felons, which is ordinarily a violation of probation.82
DETENTIONS WHILE DETAINING OTHERS: There is authority for ordering a person at the scene of a detention to stand at a certain place if, (1) it reasonably appeared that person and the detainee were associates, and (2) there was some reason to believe the person posed a threat to officers.83
EXECUTING A CIVIL COURT ORDER: Officers who are executing a civil court order may detain a person on the premises who reasonably appears to pose a threat to them or others. For example, in Henderson v. City of Simi Valley 84 officers were standing by while a minor was removing property from her mother’s home pursuant to a court order. While the officers were outside the house, the mother made threats to release her two Rottweilers on them.” The dogs were inside her house, and when she started to untie them, the officers entered and detained her. In ruling that their entry into the house was reasonable, the court noted that they “were serving as neutral third parties acting to protect all parties,” and that they “did not enter the house to obtain evidence.”
Detentions on school grounds
Officers may, of course, detain students or anyone else on school grounds if they have reasonable suspicion. In the absence of reasonable suspicion, certain special needs detentions are permitted on school grounds because of the overriding need to provide students with a safe environment and to restrict access by outsiders.85 These types of detentions are permitted if the following circumstances existed:
(1) School resource officer: These types of detentions must be conducted by a school resource officer (i.e., police officers or sheriff ’s deputies who are specially assigned to the school by their departments) or an officer who is employed by the school district.86
(2) Proper school-related interest: The detention must have served a school-related interest, such as safety or maintaining order.
DETENTIONS OF STUDENTS: Detentions of students are permitted so long as the stop was not arbitrary, capricious, or harassing. As the California Supreme Court put it:
[S]chool officials [must] have the power to stop a minor student in order to ask questions or conduct an investigation even in the absence of reasonable suspicion, so long as such authority is not exercised in an arbitrary, capricious, or harassing manner.87
For example, in In re William V.89 the court ruled that a detention was warranted even though it was based solely on a violation of a school rule.88 The facts in the case were as follows: A school resource officer at Hayward High School in Alameda County saw that a student, William, was displaying a folded red bandana. The bandanna was hanging from William’s back pocket and it caught the officer’s attention because, as he testified, colored bandanas “commonly indicate gang affiliation” and are therefore not permitted on school grounds. Furthermore, he explained that the manner in which the bandanna was folded and hanging from the pocket indicated to him that “something was about to happen or that William was getting ready for a confrontation.” The officer’s suspicions were heightened when William, upon looking in the direction of the officer, “became nervous and started pacing” and began “trembling quite heavily, his entire body, especially his hands, his lips, his jaw.” At that point, the officer detained him and subsequently discovered that he was carrying a knife. William contended that the detention was unlawful because the officer did not have reasonable suspicion to believe he was committing a crime. It didn’t matter, said the court, because “William’s violation of the school rule prohibiting bandannas on school grounds justified the initial detention.”
DETENTIONS OF NONSTUDENTS: A nonstudent may be detained during school hours to confirm he has registered with the office as required by law.90 An outsider may also be detained after school hours to confirm he has a legitimate reason for being on the school grounds.
For example, in In re Joseph F.91 an assistant principal and school resource officer at a middle school in Fairfield saw a high school student named Joseph on campus at about 3 P.M. At the request of the assistant principal, the officer tried to detain Joseph to determine whether he had registered, but Joseph refused to stop, and the officer had to forcibly detain him. As the result, Joseph was arrested for battery on a peace officer engaged in the performance of his duties.
On appeal, Joseph argued that the officer was not acting in the performance of his duties because the registration requirement does not apply after school hours. Even so, said the court, it is appropriate for officers to determine whether any outsider on school grounds has a legitimate reason for being there. This is because “schools are special places in terms of public access,” and also because “outsiders commit a disproportionate number of the crimes on school grounds.” Accordingly, the court ruled that “school officials, or their designees, responsible for the security and safety of campuses should reasonably be permitted to detain an outsider for the limited purpose of determining such person’s identity and purpose regardless of ‘school hours.’” | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/12%3A_Exigency_and_Community_Caretaking/12.2%3A_Special_Needs_Detentions.txt |
PETITIONER RESPONDENT
Darin Ryburn, et al. George R. Huff, et al.
LOCATION
Bellarmine-Jefferson High School
DOCKET NO. DECIDED BY
11-208 Roberts Court
LOWER COURT
United States Court of Appeals for the Ninth Circuit
CITATION
565 US _(2012)
GRANTED
Jan 23, 2012
DECIDED
Jan 23, 2012
Facts of the case
Darin Ryburn and Edmundo Zepeda were Burbank Police Officers. Vincent Huff was a student at Bellarmine-Jefferson High School, who was rumored to be intending to "shoot-up" the school. Ryburn, Zepeda, and other officers arrived at the school to investigate the rumors. After conducting some interviews, the officers went to Vincent Huff's home. The officers attempted to speak with Vincent Huff and his parents. Eventually, Mrs. Huff came out of the house, but she refused to let the officers to enter her home. After the police asked if there were any weapons in the house, Mrs. Huff ran back into the house. Officer Ryburn followed Mrs. Huff into the house, because he believed that Mrs. Huff's behavior was unusual and further believed that the officers were in danger. Officer Zepeda and the other officers followed Officer Ryburn into the house. The officers briefly questioned the Huffs and left after concluding that Vincent Huff did not actually pose any danger.
The Huffs brought an action against the officers. The Huffs claimed that the officers entered their home without a warrant and thereby violated the Huffs' Fourth Amendment rights. The district court entered a judgment in favor of the officers, concluding that the officers had qualified immunity because Mrs. Huff's odd behavior made it reasonable for the police to believe that they were in imminent danger. The U.S. Court of Appeals for the Ninth Circuit partially reversed the district court's ruling. The court acknowledged that the police officers could enter a home without a warrant if they reasonably believed that immediate entry was necessary to protect themselves or others from imminent serious harm, but the court concluded that the officers' belief that they were in serious immediate danger was objectively unreasonable. The officers appealed the Supreme Court.
Question
Did the police officers violate the Fourth Amendment by entering a home without a warrant when the homeowner exhibited unusual behavior leading the officers to believe they were in danger?
Conclusion
Decision for Darin Ryburn, Et Al.
Per Curiam Opinion
UNANIMOUS
Roberts
Scalia
Kennedy
Thomas
Ginsburg
Breyer
Alito
Sotomayor
Kagan
No. In an unsigned, percuriam opinion, the Court disagreed with the lower court's decision and held that there was no Fourth Amendment violation on the facts presented by this case. The Court stated that the Fourth Amendment permits the police to enter a residence if an officer has a reasonable basis for concluding that there is an imminent threat of danger. The Court determined that reasonable police officers could have come to the conclusion that the violence was imminent and that they were therefore permitted to enter a home without a warrant.
12.4: Kentucky v. King
PETITIONER RESPONDENT
Kentucky Hollis Deshaun King
LOCATION
Residence of Hollis King
DOCKET NO. DECIDED BY
09-1272 Roberts Court
LOWER COURT
Kentucky Supreme Court
CITATION
563 US 452 (2011)
GRANTED
Sep 28, 2010
ARGUED
Jan 12, 2011
DECIDED
May 16, 2011
ADVOCATES
Joshua D. Farley for the petitioner
Ann O'Connell Assistant to the Solicitor General, Department of Justice, as amicus curiae, supporting the petitioner
Jamesa J. Drake for the respondent
Facts of the case
Police officers in Lexington, Ky., entered an apartment building in pursuit of a suspect who sold crack cocaine to an undercover informant. The officers lost sight of the suspect and mistakenly assumed he entered an apartment from which they could detect the odor of marijuana. After police knocked on the door and identified themselves, they heard movements, which they believed indicated evidence was about to be destroyed. Police forcibly entered the apartment and found Hollis King and others smoking marijuana. They also found cash, drugs and paraphernalia. King entered a conditional guilty plea; reserving his right to appeal denial of his motion to suppress evidence obtained from what he argued was an illegal search.
The Kentucky Court of Appeals affirmed the conviction, holding that exigent circumstances supporting the warrantless search were not of the police's making and that police did not engage in deliberate and intentional conduct to evade the warrant requirement. In January 2010, the Kentucky Supreme Court reversed the lower court order, finding that the entry was improper. The court held that the police were not in pursuit of a fleeing suspect when they entered the apartment, since there was no evidence that the original suspect even knew he was being followed by police.
Question
Does the exclusionary rule, which forbids the use of illegally seized evidence except in emergency situations, apply when the emergency is created by lawful police actions?
Conclusion
8–1 Decision for Kentucky Majority Opinion by Samuel A. Alito,
FOR AGAINST
Sotomayor
Kagan
Breyer
Kennedy
Roberts
Alito
Scalia
Thomas
Ginsburg
The Supreme Court reversed and remanded the lower court order in a decision by Justice Samuel Alito. "The exigent circumstances rule applies when the police do not create the exigency by engaging or threatening to engage in conduct that violates the Fourth Amendment," Alito wrote for the majority. Justice Ruth Bader Ginsburg dissented, contending that "the Court today arms the police with a way routinely to dishonor the Fourth Amendment's warrant requirement in drug cases." | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/12%3A_Exigency_and_Community_Caretaking/12.3%3A_Huff_v._City_of_Burbank.txt |
There’s a simple way for the police to avoid many complex search and seizure problems: Get a search warrant.1
That’s good advice, except for two things: Officers cannot simply “get” a search warrant; they must apply for one. And there is nothing “simple” about the application process. On the contrary, even with the advent of email warrants it is one of the more tedious and vexing legal hoops through which officers are required to jump.2 While some veterans, having suffered through the process for many years, can crank out search warrants with relative ease, for most officers it’s a challenge. In this article, we hope to make it much less challenging. But before we begin, it will be helpful to briefly explain the organization of the subject and some of its terminology. The legal issues can be divided into two broad categories. The first consists of the various requirements for establishing probable cause, a subject we covered in the Fall 2008 edition. The second—which is the subject of this article—covers the requirements as to the form and content of the warrant and, except for demonstrating probable cause, the affidavit. Although some of these requirements are technical in nature, most are substantive and, if not complied with, will invalidate a warrant just as surely as the absence of probable cause.
As for terminology, the following are the principal terms that are used in the law of search warrants and which are used in this article:
AFFIDAVIT: An affidavit is a document signed under penalty of perjury.3
MAGISTRATE: In the context of search warrants, the term “magistrate” is synonymous with “judge.”4 In this article, we use the terms interchangeably.
GENERAL WARRANT: A warrant will be deemed “general”—and therefore unlawful—if it contained such a broad description of the evidence to be seized that officers were permitted to conduct a virtually unrestricted search of the premises.5 Examples include warrants to search for “all evidence” or “stolen property.” Unless the severance rule applies (discussed later), evidence seized pursuant to a general warrant will be suppressed.
OVERBROAD WARRANT: A warrant is “overbroad” if its affidavit failed to demonstrate probable cause to believe that each of the things that officers were authorized to search for and seize were, in fact, evidence of a crime and would be found in the place to be searched.6 Overbreadth is a fatal defect unless the severance rule applies.
PARTICULARITY: The term “particularity” refers to the constitutional requirement that a search warrant must clearly describe (1) the places and things that officers may search, and (2) the property they are permitted to search for and seize.7 (The terms “overbreadth” and “particularity” are often confused.8)
The Affidavit
A search warrant affidavit is a document signed under penalty of perjury that contains the following: (1) the statement of probable cause, (2) descriptions of the place to be searched and the evidence to be seized, (3) justification for implementing special procedures (if any), and (4) other information required by California law.
The statement of probable cause
Writing the statement of probable cause is, by far, the most difficult and time consuming part of the process, as the affiant must persuade the judge there is a fair probability that the evidence he is seeking exists, that it is now located at the place to be searched, and that it will still be there when the warrant is executed.9
ORGANIZE THE FACTS: The affiant should usually start by jotting down the main facts upon which probable cause will be based. This will reduce the chances that important facts are inadvertently left out.10 Although a statement of probable cause will not be judged as “an entry in an essay contest,”11 the affiant should present the facts in a logical sequence. This is especially important in complex cases.12
EDIT AND SIMPLIFY: The statement of probable cause should seldom include everything that officers have learned about the crime under investigation and the suspect. Instead, it “need only furnish the magistrate with information, favorable and adverse, sufficient to permit a reasonable, common sense [probable cause] determination.”13
WHO SHOULD BE THE AFFIANT? The affiant should normally be the investigator who is “most directly involved in the investigation and most familiar with the facts stated in the affidavit.”14 While most affiants are peace officers, anybody can be one; e.g., a prosecutor or an informant.15
TRAINING AND EXPERIENCE: The affiant should include a brief statement of his training and experience if (1) the existence of probable cause will be based, even partly, on his opinion concerning the meaning or significance of information contained in the affidavit; or (2) the description of the evidence to be seized will be based in part on an inference he has drawn. (We will discuss descriptions based on training and experience later in this article.) Note that the affiant need not have qualified as an expert witness in court to offer an opinion.16
USING ATTACHMENTS: Probable cause may be based in part on information that is contained in another document, such as a police report, a fingerprint or DNA report, a witness’s statement, or a photograph. The subject of incorporating attachments into affidavits and warrants is covered later in the section on describing evidence.
SHOULD A PROSECUTOR REVIEW IT? A prosecutor (preferably one who knows the law of search and seizure) should ordinarily review an affidavit if there are legal issues with which the affiant is unfamiliar or uncertain. A review is also recommended if the existence of probable cause is a close question. This is because a prosecutor’s approval is a circumstance that the courts will consider in determining whether the good faith rule applies.17
Other affidavit requirements
In addition to the statement of probable cause, the affidavit must include the following.
DESCRIPTIVE INFORMATION: The affidavit must contain descriptions of (1) the person, place, or thing to be searched; and (2) the evidence to be seized.18 Although this information must also appear on the warrant, it must be included in the affidavit because the affiant must swear that it is true, and only the information contained in the affidavit is subject to the oath. The requirements pertaining to the quality and quantity of descriptive information are covered later in this article.
GROUNDS TO UTILIZE SPECIAL PROCEDURES: The affiant will usually request authorization to implement one or more special procedures, such as night service, no-knock entry, or affidavit sealing. While such authorization must appear on the warrant, the affidavit must contain the facts upon which the request is based. We will cover the subject of special procedures in the Summer 2011 edition.
WHEN TO SIGN: The affiant must not sign the affidavit until he is directed to do so by the judge. This is because the judge must state on the warrant that the affidavit was “sworn to and subscribed before me.” See “The jurat,” below.
The Warrant
Technical Requirements
Because a search warrant is a court order,22 it must contain the information that is necessary to constitute an enforceable judicial command, plus certain information required by California statute.
THE HEADING: Like any court order, the heading must identify the issuing court:
SUPERIOR COURT OF CALIFORNIA
County of
IDENTIFY THE OFFICERS: The warrant must identify the officers who are ordered to conduct the search. Thus, most warrants begin with the following: The People of the State of California to any peace officer in the County of .23
THE OATH: The affiant must sign the affidavit under oath; e.g., “I declare under penalty of perjury that the foregoing is true.”19 By doing so, he is swearing that (1) the information within his personal knowledge is accurate; and (2) the information that was not within his personal knowledge was, in fact, received by him from others, and that he had no reason to doubt its accuracy.20 Note it is inappropriate for affiants to swear that their information establishes probable cause (this is a legal determination to be made by the judge), or that they “believe” they have probable cause (this is irrelevant). As the court noted in People v. Leonard, “Warrants must be issued on the basis of facts, not beliefs.”21
WHAT COUNTY? The county that is listed must be the same as the county in which the issuing judge sits. For example, if the warrant was issued by a judge in Alameda County, the warrant must be directed to “any peace officer in the County of Alameda.” As we will discuss in the Summer 2011 edition, this requirement will not bar a judge from issuing a warrant to search a person, place, or thing located in another county in California.
THE JURAT AND IDENTIFICATION OF THE AFFIANT:
The warrant must identify the affiant,24 and the judge must confirm by means of the jurat that the affiant signed the affidavit under oath in the judge’s presence; e.g., “An affidavit by [name of affiant], sworn and subscribed before me on this date . . . ” 25 Note that if the affiant is a confidential informant who is covered under California’s nondisclosure privilege, the warrant may be modified as follows: “An affidavit by a confidential informant . . .” 26
DISPOSITION OF SEIZED EVIDENCE
The warrant must include instructions as to what the officers must do with any evidence they seize. Although Penal Code sections 1523 and 1529 state that the officers must bring the evidence to the judge, Penal Code sections 1528(a) and 1536 state that the officers must retain it pending further order of the court. Because judges do not want officers to deliver to their chambers loads of drugs, firearms, stolen property, and other common fruits of search warrants, the Court of Appeal has ruled that the evidence must be retained by the officers unless the warrant directs otherwise.27
Note that because the officers hold the evidence on behalf of the court, they may not transfer possession of it to any other person or agency except per further court order. As the California Supreme Court explained, “Law enforcement officers who seize property pursuant to a warrant issued by the court do so on behalf of the court, which has authority pursuant to Penal Code section 1536 to control the disposition of the property.”28
EVIDENCE CLASSIFICATION: Penal Code section 1524(a) states that search warrants may be issued for certain types of evidence, depending mainly on whether the crime under investigation was a felony or misdemeanor. (See this footnote for a listing of seizable evidence.29) Consequently, the affiant should specify (usually by checking one or more preprinted boxes) that the listed evidence falls into one or more of these categories.
The question has arisen whether officers who are investigating a misdemeanor can obtain a warrant to search for evidence that is not listed in Penal Code section 1524(a). It is arguable that a judge could do so because the statute does not say that judges are prohibited from issuing warrants for other types of evidence; it is merely a permissive statute, and the distinction between prohibitive and permissive statutes has long been recognized by the courts.30 Furthermore, evidence that was obtained by means of a warrant that was constitutionally valid cannot be suppressed on grounds that the warrant violated a state statute.31 As a practical matter, however, judges may be unwilling to issue warrants that do not comply with state law.
FORMS AVAILABLE: Search warrant forms and related documents are available to officers and prosecutors. For information, go to our website: a link to the Alameda County District Attorney's website for law enforcement officers and prosecutors. (click on “Forms”).
Describing the Place To Be Searched
The requirement that search warrants describe the people, places, and things that may be searched will be deemed satisfied if the quality and quantity of the descriptive information is such that the search team can “ascertain and identify the place intended” with “reasonable effort.”32 While this “reasonable effort” test is somewhat ambiguous, as we will now discuss, the courts have generally agreed on what descriptive information will suffice.
SINGLE-FAMILY RESIDENCES: In most cases, a simple street address will do if the place to be searched is a house, apartment, condominium, or motel room.33 If, however, street signs or unit numbers are lacking or obscured, the warrant must include a physical description of the premises or some other information that will direct the officers to the right place; e.g., a photograph, diagram, map, or image from Google Earth or Google Street View.34 Although affiants sometimes describe the premises by inserting the name of the owner, this is not a requirement.35 Moreover, it would ordinarily be of dubious value because ownership is a legal determination that seldom can be made at the scene prior to entry.
DETACHED BUILDINGS: If officers have probable cause to search detached structures on residential property (e.g., detached garage, storage shed), the warrant must indicate which structures may be searched. There are two ways to do this. First, the affiant can describe their physical characteristics; e.g., “The house at 415 Hoodlum Place and the red storage shed located approximately 100 feet behind the house.” The other method is to insert the word “premises” in the description of the place to be searched (e.g., “The premises at 415 Hoodlum Place”) as the courts have interpreted the word “premises” as expanding the scope of the search to all outbuildings that are ancillary to the main house.36
MULTI-OCCUPANT RESIDENCES: A multi-occupant residence is loosely defined as a building that has been divided into entirely separate living units, each under the exclusive control of different occupants. For example, a motel is a multi-occupant building, while a single motel room is a single-family residence. Another example of a multiple-occupant residence (although unusual) is found in Mena v. Simi Valley 37 where a single-family house was occupied by several unrelated people, each of whom occupied rooms that were “set up as studio apartment type units, with their own refrigerators, cooking supplies, food, televisions, and stereos.”
The rule regarding multiple-occupant residences is straightforward: If, as is usually the case, officers have probable cause to search only a particular living unit, the warrant must direct them to search only that unit; e.g., “apartment 211,” “the lower unit of the two-story duplex,” “room number one of the Bates Motel.”38 As the court explained in People v. Estrada, a warrant for a multiple-occupant residence must “limit the search to a particular part of the premises either by a designation of the area or other physical characteristics of such part or by a designation of its occupants.”39
Note that a single-family residence does not turn into a multiple-occupant residence merely because the occupants had separate bedrooms; e.g., roommates. For example, in People v. Gorg 40 officers in Berkeley developed probable cause to believe that a man named Fontaine was selling marijuana out of a three-bedroom flat that he shared with Gorg and another man. So they obtained a warrant to search the flat and, in the course of the search, found marijuana in Gorg’s bedroom. Gorg argued that the flat was a multiple-occupant residence and, therefore, the search of his bedroom was unlawful because the warrant did not restrict the search to Fontaine’s bedroom and the common areas. The court disagreed, explaining:
[The warrant] was issued for a search of the lower flat in question, and Fontaine was named as the one occupying the named premises. Actually three people lived in this flat, sharing the living room, kitchen, bath and halls. The three bedrooms opened on these rooms and were not locked. All of the rooms constituted one living unit.
BUSINESSES: If the business occupies the entire building, and if there is probable cause to search the entire business, the warrant can simply identify the building by its street address and direct officers to search the entire structure. But, as with multipleoccupant residences, a more restrictive description will be required if probable cause is limited to a certain area or room.41
DETACHED COMMERCIAL STRUCTURES: If officers also have probable cause to search structures that are ancillary to the main business office, the affiant should ordinarily describe each building for which probable cause exists. This is because the relationship between the various structures on commercial property is often ambiguous.
VEHICLES: It is sufficient to identify vehicles by their license number and a brief description. If the license number is unknown or if there are no plates on the vehicle, it may be identified by its VIN number, or its location and a detailed description.42 A warrant may authorize a search of “all vehicles” on the premises, but only if there is probable cause to believe that at least some of the listed evidence will be found in each vehicle.43
PEOPLE A warrant to search a person must identify the person by name, physical description, or both.44 If necessary, a photograph of the person may be attached to the warrant; e.g., DMV or booking photo.45 A warrant may authorize a search of “all residents” of the premises or everyone who is present when officers arrive, but only in those rare cases in which the affidavit establishes probable cause to believe that at least some of the listed evidence will be found on every resident or occupant.46
COMPUTERS: If officers have probable cause to search a home or business for information, data, or graphics, it is usually reasonable to believe that some or all of it has been stored in a computer or external storage device. But officers will seldom know what type of computer or device they will find; and the only way they can learn is to obtain a warrant. A classic Catch-22 situation.
Some courts have resolved this dilemma by ruling that authorization to search all computer devices on the premises will be implied if the warrant authorized a search for data that could have been stored digitally.47 But the better practice is to seek express authorization by particularly describing the data or graphics to be seized, then adding language that authorizes a search for it in any form in which it could have been stored; e.g., “[After particularly describing the data to be seized] whether stored on paper or on electronic or magnetic media such as internal or external hard drives, diskettes, backup tapes, compact disks (CDs), digital video disks (DVDs), optical discs, electronic notebooks, video tape, or audio tape.” 48
Describing the Evidence
Next to establishing probable cause, the most difficult part of the application process is usually describing the evidence to be seized. This is because officers will not know exactly what the evidence looks like unless they had seen it. As we will discuss, however, the problem is not insurmountable, as the courts have ruled that descriptions may be based on reasonable inference.
But before going further, we must stress that providing a description of the evidence is not a mere “technical” requirement that requires little effort. On the contrary, it is crucial because a detailed description provides the courts with the necessary assurance that the officers will confine their search to places and things in which specific evidence may be found, and that they will seize only evidence for which probable cause exists. Thus, the Ninth Circuit noted that search warrants will be deemed invalid “when they are so bountiful and expansive in their language that they constitute a virtual, all-encompassing dragnet of personal papers and property to be seized at the discretion of the State.”49
It is understandable that affiants may worry that their searches will be unduly restricted if they describe the evidence too narrowly. But this is seldom a problem because most warrants include authorization to search for small objects (such as drugs) or documents (such as indicia) that can be found almost anywhere on the premises.
The “particularity” requirement
While a warrant must contain a description of the evidence to be seized, not just any description will do. The description must be “particular,” a word having such significance that it was incorporated into the Fourth Amendment to the United States Constitution.50 Thus, the Supreme Court ruled that “a search conducted pursuant to a warrant that fails to conform to the particularity requirement of the Fourth Amendment is unconstitutional.”51
What, then, constitutes a “particular” description? Although the issue “has been much litigated with seemingly disparate results,”52 a description will ordinarily suffice if it imposes a “meaningful restriction” on the scope of the search,53 or if it otherwise “sets out objective standards”54 by which officers can determine what they may, and may not, search for and seize.
Later, we will discuss specific applications of this test. But first, it is necessary to cover the principles that the courts apply in determining whether a description was sufficiently particular, and also some practices that have tended to cause problems.
PRACTICAL NOT ELABORATEDESCRIPTIONS
While some courts in the past elevated form over substance and required technical precision and elaborate specificity,55 that has changed. Today, as the Court of Appeal observed, “the requirement that a search warrant describe its objects with particularity is a standard of ‘practical accuracy’ rather than a hypertechnical one.”56
Consequently, a description will suffice if it contains just the amount of information that is reasonably necessary to identify the evidence to be seized.57 Or, in the words of the First Circuit, the warrant must provide “clear, simple direction”:
Specificity does not lie in writing words that deny all unintended logical possibilities. Rather, it lies in a combination of language and context, which together permit the communication of clear, simple direction.58
TOTALITY OF DESCRIPTIVE INFORMATION
In determining whether a description was sufficiently particular, the courts will consider the descriptive language as a whole, meaning they will not isolate individual words and ignore the context in which they appeared.59 As the Supreme Court observed, “A word is known by the company it keeps.”60
REASONABLY AVAILABLE INFORMATION
As noted, it happens that, despite their best efforts, officers are simply unable to provide a detailed description of the evidence. In these situations, a description will ordinarily suffice if the affiant provided as much descriptive information as he had or could have obtained with reasonable effort (including, as we will discuss later, as much descriptive information as he could reasonably infer).61 Thus, the Eleventh Circuit pointed out the following in U.S. v. Santarelli:
There are circumstances in which the law enforcement officer applying for a warrant cannot give an exact description of the materials to be seized even though he has probable cause to believe that such materials exist and that they are being used in the commission of a crime. In these situations we have upheld warrants when the description is as specific as the circumstances and the nature of the activity under investigation permit.62
This also means, however, that a warrant is apt to be invalidated if officers could have—but did not— provide a particular description. For example, in U.S. v. Stubbs the court ruled that a warrant obtained by IRS agents to search the defendant’s office for evidence of tax evasion was not sufficiently particular because, as the court pointed out, “The IRS knew both what the seizable documents looked like and where to find them, but this information was not contained in the warrant.”63
Similarly, in Center Art Galleries v. U.S.64 officers developed probable cause to search several art galleries for stolen paintings by Salvador Dali. In the course of the investigation, they obtained warrants to search the defendant’s galleries for, among other things, “sales records and customer/client information, lithographic and etching plates.” But the court ruled this description was insufficiently particular because it “failed to limit the warrants to items pertaining to the sale of Dali artwork.” This failure, said the court, was especially egregious because “the government had the means to identify accounts which may have involved Dali artwork. The lead government investigator was aware that a special card was created for the file of all clients who were interested in Dali artwork.”
Problem areas
Before we discuss the ways in which officers can provide a particular description, it is necessary to address some issues and practices that have tended to cause problems or confusion.
BOILERPLATE: In the context of search warrants, the term “boilerplate” means a list—usually lengthy— of descriptions copied verbatim from other warrants and affidavits.65 Because boilerplate is now commonly stored in computer files, it now takes only a few clicks or keystrokes to provide pages of boilerplated descriptions—much of it worthless, if not potentially destructive.
The problem with boilerplate is that, unless it has been carefully edited, the descriptions it contains often have little or no resemblance to the evidence for which there is probable cause. Thus, warrants that authorize searches for boilerplated evidence often contain overbroad descriptions that may render the warrant invalid unless, as discussed below, the severance rule applies. This does not mean that officers should never utilize boilerplate. As we will discuss later, it may properly be used to provide descriptions of evidence that can only be described by inference.
TRAINING AND EXPERIENCE: Like boilerplate, statements by affiants of their training and experience tend to be too lengthy and are frequently unnecessary. In the context of describing evidence, they are usually relevant only if the description was based on an inference that, in turn, was based on the affiant’s training and experience; e.g., a description of drug paraphernalia based on the affiant’s knowledge of the common instrumentalities used by drug users and traffickers. (For a discussion of training and experience as it pertains to establishing probable cause, see “The Affidavit,” above.)
“AMONG OTHER THINGS: Affiants will sometimes provide a particular description of some evidence, then add some language that authorizes a search for similar things that have not been described; e.g., “including, but not limited to,” “among other things,” “etc.” Such indefinite language—sometimes called a “wildcard”66 or a “general tail”67—may render a warrant insufficiently particular if, when considered in context, it authorizes an unrestricted search. For example, a warrant that simply authorizes a search for “Heroin, among other things” is insufficiently particular (and also overbroad) because it contains no restriction on what officers may search for and seize. Thus, in Aday v. Superior Court 68 the California Supreme Court invalidated a warrant to search for “all other records and paraphernalia” connected with the defendants’ business because, said the court, “[t]he various categories, when taken together, were so sweeping as to include virtually all personal business property on the premises and placed no meaningful restriction on the things to be seized.”
Similarly, in U.S. v. Bridges 69 the affiant described the evidence to be seized as all records relating to the suspect’s clients and victims, “including but not limited to” certain records that were particularly listed in the warrant. But because this language effectively authorized a search for “all records”— regardless of whether they were particularly described—the court ruled the warrant was invalid. As it pointed out, “[I]f the scope of the warrant is not limited to the specific records listed on the warrant, it is unclear what is its precise scope or what exactly it is that the agents are expected to be looking for during the search.”
This does not mean that wildcards are forbidden. In fact, there are three situations in which they are regularly used without serious objection. First, there are situations in which the evidence is limited to fruits or instrumentalities of a certain crime, and the wildcard could be interpreted as merely providing descriptive examples of seizable evidence pertaining to that crime.70 For instance, in Toubus v. Superior Court 71 a warrant authorized a search for “any papers or writings, records that evidence dealings in controlled substances, including, but not limited to address books, ledgers, lists, notebooks, etc.” In ruling that this language did not render the warrant insufficiently particular, the court pointed out that it permitted a seizure of only those things pertaining to “dealings in controlled substances.”
Second, a wildcard may be appropriate when a warrant authorized a search of a crime scene, but officers could not be expected to know exactly what types of evidence pertaining to the crime they would find. For example, in People v. Schilling 72 the body of a woman was discovered in the Angeles National Forest. Having developed probable cause to believe that Schilling had shot and killed the woman in his home, a homicide detective with the Los Angeles County Sheriff’s Department obtained a warrant to search Schilling’s house for, among other things, “scientific evidence, including but not limited to fingerprints, powder burns, blood, blood spatters, photographs, measurements, bullet holes, hair, fibers.” On appeal, Schilling argued that the “but not limited to” language rendered the warrant insufficiently particular, but the court disagreed, pointing out that the warrant “simply authorized seizure of additional scientific evidence” pertaining to the murder that the affiant “was unable to detail.”
Third, as we will discuss later, wildcards are commonly used to provide examples of the types of indicia that officers may seize.
THE SEVERANCE EXCEPTION: If the affiant fails to satisfactorily describe some, but not all, of the listed evidence, the courts will ordinarily suppress only those items that were inadequately described.73 For example, if items A and B were adequately described but item C was not, it is likely that only item C would be suppressed. The severance exception will not, however, be applied if the inadequately-described evidence so predominated the warrant that it effectively authorized a general search. As the Ninth Circuit observed, “[S]everance is not available when the valid portion of the warrant is a relatively insignificant part of an otherwise invalid search.”74 For example, in Burrows v. Superior Court the court ruled that, “[a]ssuming arguendo that the warrant is severable, the direction to seize ‘any file or documents’ relating to the [suspects] is too broad to comport with constitutional requirements.”75 (Note that severance may also be appropriate when the affidavit fails to establish probable cause to search for some— but not all—of the listed evidence.76)
Basics of providing particular descriptions
Although the courts understand that officers may sometimes be unable to provide much descriptive information, they expect them to utilize all reasonably available means to limit, at least to some extent, the scope of their warranted searches. The following are the most common ways in which this is done.
AVOID GENERAL TERMS: The use of precise language to describe evidence is the mark of a particular description. The following are examples:
• illegal drugs consisting of heroin and crack cocaine 77
• records relating to loan sharking and gambling, including pay and collection sheets, lists of loan customers, loan accounts, line sheets, bet slips, and tally sheets 78
• blue plaid long-sleeved flannel shirt 79
• fingerprints, powder burns, blood, blood spatters, bullet holes 80
• vehicles with altered or defaced identification numbers 81
• a 14-inch security hole opener cutter attached to a hole opener 82
• oil and water drill bits in sizes from four inches to 18 inches, having altered or defaced serial numbers 83
In contrast, the following descriptions were plainly inadequate:
• stolen property 84
• all other property owned by [the theft victim].85
• any and all illegal contraband 86
• certain personal property used as a means of committing grand larceny 87
• all business records and paraphernalia 88
• other evidence 89
DESCRIBE BY LOCATION: If officers know exactly where on the premises the evidence is located (e.g., in a certain room, closet, cabinet, file, or box), this information may be included in the description.90 But unless officers are certain that the evidence will be found only in that location when the warrant is executed, the affiant should explain that this information is being provided only to assist in the identification of evidence, not to restrict the scope of the search.
UTILIZING ATTACHMENTS: One of the most efficient means of inserting information into affidavits and warrants—whether to establish probable cause or to provide a description—is to incorporate documents that already contain that information; e.g., witness statements, prior affidavits, police reports, autopsy reports, rap sheets, business records, maps, photographs. As the court observed in State v. Wade, incorporation “is a recognized method of making one document of any kind become a part of another separate document without actually copying it at length in the other.”91
An attachment will not, however, be deemed incorporated merely because it was submitted to the judge along with the affidavit and search warrant.
Instead, the law imposes three requirements that are designed to eliminate any confusion as to the status of supplementary documents:
1. IDENTIFY THE ATTACHMENT: The affiant must clearly identify the document that is being incorporated into the warrant or affidavit.92 This is typically accomplished by assigning it an exhibit number or letter, then writing that number or letter in a conspicuous place at the top of the attachment.
2. INCORPORATE BY REFERENCE: The affiant must then insert into the search warrant or affidavit “appropriate words of reference”93 or other “clear words”94 that give notice to the judge that the identified document is being incorporated.95 As the Third Circuit explained in United States v. Tracey, “Merely referencing the attached affidavit somewhere in the warrant without expressly incorporating it does not suffice.” 96 Although there are no “magic” or required words of incorporation,97 it is usually best to use the direct approach; e.g., “The police report containing the list of stolen property, identified as Exhibit 4, is attached hereto and incorporated by reference.” 98
3. PHYSICAL ATTACHMENT: If the attachment is being utilized solely to establish probable cause in the affidavit, the courts do not require that it be physically attached to the affidavit 99 (but it’s a good practice). If the attachment is used to describe the place to be searched or the evidence to be seized, the United States Supreme Court indicated in Groh v. Ramirez that the attachment need only be “present” when the warrant is served; i.e., physical attachment is not required.100 But because some pre-Groh cases in California required physical attachment,101 it is recommended that officers avoid this issue by affixing to the warrant any attachments containing descriptive information.
Two other things about attachments to warrants and affidavits. First, they must be legible.102 Second, because judges are required to read all attachments to affidavits,103 officers should not incorporate lengthy attachments that contain only a small amount of relevant information. Instead, this information should be extracted from the attachment or summarized in the affidavit.
SEARCH PROTOCOLS: If the affiant is unable to particularly describe the evidence to be seized, but there is a procedure that will enable the search team to identify it after they enter the premises, it may be deemed sufficiently described if the search warrant sets forth a procedure—commonly known as a “protocol”—by which officers could make the determination. For example, if officers want to look for stolen property that may have been intermingled with similar looking items, they may seek authorization to employ a protocol that would permit them to seize items that conform to certain criteria; e.g., a particular VIN or serial number.104
One of the most common uses for protocols today is in computer searches when officers expect to find seizable files intermingled with non-seizable files. In such cases, they may seek authorization to conduct the search pursuant to a protocol that sets forth the manner in which the search team can distinguish between the two. For example, in one case the protocol required “an analysis of the file structure, next looking for suspicious file folders, then looking for files and types of files most likely to contain the objects of the search by doing keyword searches.”105
Having covered the general principles pertaining to descriptions of evidence, we will now look at the ways in which evidence may be described when the description is based on direct observation or inference. We will also examine warrants to search for entire classes of items and documents, including documents stored in computers.
Description based on direct observation
Officers will sometimes seek a warrant to search for evidence that an officer, victim, or witness had previously observed, such as property that the victim of a burglary had reported stolen, a handgun or clothing that was seen in a surveillance video, or drug lab equipment that an undercover officer or informant had seen when negotiating a drug purchase. Describing this type of evidence is, of course, much easier than describing evidence whose appearance can only be based on inference. But, as discussed earlier, because the affiants in such cases have the ability to provide a particular description, the courts will readily invalidate a warrant if they fail to do so.
For example, in Millender v. County of Los Angeles 106 a woman notified sheriff ’s deputies that her boyfriend, Jerry Bowen, had tried to shoot her during an argument. Although the woman described the weapon as a “black sawed-off shotgun with a pistol grip,” and even though she provided deputies with a photograph of the weapon, they obtained a warrant to search Bowen’s house for the following: “All handguns, rifles, or shotguns of any caliber, or any firearms capable of firing ammunition.” In ruling that this language rendered the warrant insufficiently particular, the court said:
[W]here the police do have information more specifically describing the evidence or contraband, a warrant authorizing search and seizure of a broader class of items may be invalid.
Another example is found in People v. Tockgo 107 where officers in Los Angeles developed probable cause to believe that boxes containing stolen cigarettes were located in a certain liquor store. They had also learned from the victim that certain invoice numbers were printed on each box, that each box contained a tax stamp, and that the cigarette cartons were sealed with a unique colored glue. Although this information was contained in the affidavit, it was omitted from the warrant, which simply described the evidence to be seized as “cigarettes, cellophane wrappers, cigarette cartons.” In ruling that this description was insufficient, the court pointed out that “[t]he vice of this uncertainty is particularly objectionable because the procuring officer’s affidavit provided a ready means for effective description and identification of the particular cigarette packages to be seized.”
Descriptions based on inference
In many cases, an affiant cannot provide a particular description of evidence inside a home or business because, for example, no officer or informant had been inside or because the evidence was hidden. As we will now discuss, in situations such as these officers may ordinarily provide a description that, based on their training and experience, can be reasonably inferred.
FRUITS AND INSTRUMENTALITIES OF A CRIME
Descriptions are commonly based on inference when officers have probable cause to believe that the premises are being used to carry out a certain type of criminal activity and, thus, they have probable cause to believe that the premises contain the common fruits and instrumentalities of such a crime.108 For example, in United States v. Holzman 109 officers in Scottsdale, Arizona arrested Holzman and Walsh for using and possessing stolen credit cards. Having probable cause to believe they were co-conspirators in an identify theft operation, but not knowing exactly what fruits and instrumentalities they possessed, an officer obtained a warrant to search their hotel rooms for, among other things, “All credit cards under miscellaneous issuance names and account numbers” and “credit card drafts under miscellaneous issuance and names.” In ruling that these descriptions were sufficiently particular, the court said, “In the absence of complete and detailed knowledge on the part of the police, the magistrate was justified in authorizing the search for these generic classes of items.”
Similarly, if the affiant has probable cause to believe that the suspect is selling drugs out of his house, a general description of typical sales paraphernalia and instrumentalities ought to suffice; e.g., items commonly used to ingest, weigh, store, and package drugs; documents identifying buyers and sellers; drug transaction records.110
Another example is found in cases where officers are seeking a warrant to search for evidence of sexual exploitation of a child. Here, a description might include such things as sexually explicit material or paraphernalia used to lower the inhibition of children, sex toys, photography equipment, address ledgers, journals, computer equipment, digital and magnetic storage devices.111 Finally, a warrant to search for evidence of loan sharking or gambling might authorize a search for pay and collection sheets, lists of loan customers, loan accounts and telephone numbers, line sheets, and bet slips.112
EVIDENCE AT CRIME SCENES: At crime scenes, officers will often have probable cause to believe that certain evidence will be found on the premises depending on the nature and freshness of the crime. But because they cannot know exactly what’s there, the courts permit them to describe the evidence in terms of what is commonly found at the scenes of such crimes.
For example, in People v. Schilling,113 discussed earlier, an LASD homicide detective developed probable cause to believe that Schilling had shot and killed an out-call masseuse whose body had been dumped in a remote area. Because the woman had an appointment to meet with Schilling at his home shortly before the approximate time of death, the detective sought a warrant to search the house for evidence that, based on his training and experience, would likely be found at the scene of a shooting; namely, “scientific evidence, including but not limited to fingerprints, powder burns, blood, blood spatters, bullet holes, hairs, fibers.” The search turned up incriminating evidence which, according to Schilling, should have been suppressed because the description was too general. But the court disagreed, saying it “was clearly a particularized specification of the scientific evidence that could reasonably be obtained in defendant’s residence in light of the facts set forth in [the] affidavit.”
Warrant to seize entire class
A warrant may authorize the seizure of every item in a broad class (e.g., all credit cards, all firearms) if there is a fair probability that all such items are evidence. For example, in Vitali v. U.S.114 officers obtained a warrant to search Vitali’s offices for all Speidel watch bands on the premises, having developed probable cause to believe that he was selling these types of watch bands from a back room. In ruling the warrant was sufficiently particular, the First Circuit said:
Where goods are of a common nature and not unique there is no obligation to show that the ones sought (here a substantial quantity of watch bands) necessarily are the ones stolen, but only to show circumstances indicating this to be likely.
If officers have probable cause to believe that only some of the items in the class are evidence, the warrant may authorize a search for, and inspection of, all items in the class to determine which are seizable if the warrant provides them with some criteria for making this determination. As the Ninth Circuit explained:
When there is probable cause to believe that premises to be searched contains a class of generic items or goods, a portion of which are stolen or contraband, a search warrant may direct inspection of the entire class of all of the goods if there are objective, articulated standards for the executing officers to distinguish between property legally possessed and that which is not.115
An example of a case in which a warrant failed to provide officers with an adequate means of identifying seizable evidence in a class is found in U.S. v. Klein.116 Here, officers developed probable cause to believe that the owners of a music store were selling pirated 8-track tapes. So they obtained a warrant to search the store for “8-track electronic tapes and tape cartridges which are unauthorized ‘pirate’ reproductions.” In ruling the warrant was not sufficiently particular, the court noted that “the affidavit and the warrant failed to provide any before the fact guidance to the executing officers as to which tapes were pirate reproductions.”
In cases such as Klein where a cursory examination of a class of items may be insufficient to identify seizable evidence, the warrant may include a protocol (discussed on page 14), describing a procedure that officers must utilize to make the determination. For example, in U.S. v. Hillyard 117 FBI agents developed probable cause to believe that stolen vehicles were being stored in a certain wrecking yard. Although the agents were able to describe some of the stolen vehicles, they had probable cause to believe there were others on the premises. So they obtained a warrant authorizing a seizure of the particularly described vehicles plus any others on the premises that “possess altered or defaced identification numbers or which are otherwise determined to be stolen.” In upholding the warrant, the court pointed out that “the affidavit explained that vehicle alterations could be discovered by comparing secret identification numbers with those openly displayed, that true numbers could be checked with law enforcement computerized lists.”
Describing documents and computer files
The rule that warrants must describe the evidence to be seized with reasonable particularity seems to be enforced more strictly when the evidence consists of documents, whether hard copies or computer files. There are four reasons for this. First, a search for documents is especially intrusive as officers must usually examine every room, container, and computer file in which they may be found. Second, every document and computer file on the premises must ordinarily be read (or at least skimmed) to determine whether it is covered under the warrant.118 Third, the reading of documents constitutes “a very serious intrusion into personal privacy.”119 Fourth, officers will usually have some information that would have made it possible to distinguish between relevant and irrelevant documents.
Even so, the courts require only reasonable particularity. As the court explained in U.S. v. Phillips:
A warrant need not—and in most cases, cannot—scrupulously list and delineate each and every item to be seized. Frequently, it is simply impossible for law enforcement officers to know in advance exactly what business records the defendant maintains.120
Consequently, a warrant to search for documents, like other types of warrants, will be deemed sufficiently particular if officers described the documents as best they could.
DESCRIPTION LIMITED BY SENDER, RECIPIENT, DATE:
If the relevance of a document depends on who sent it, its date, or to whom it was addressed, this information should be included as it will significantly narrow the description.121
DESCRIPTION LIMITED BY CRIME OR OTHER SUBJECT
MATTER: Probably the most common method of describing documents is to state their subject matter, such as the nature of the crime for which the documents are evidence.122 The following are some examples:
• “Loan records reflecting the \$500,000 teamster trust fund loan and its subsequent disbursement.”123
• “Drug trafficking records, ledgers, or writings identifying cocaine customers, sources.”124
• Documents “pertaining to the Windward International Bank.”125
• “All property constituting evidence of the crimes of making and conspiring to make extortionate extensions of credit, financing extortionate extensions of credit, and collections of and conspiracy to collect extortionate extensions of credit.”126
• “Books” and “records” that “are being used as means and instrumentalities” by the perpetrators of hijackings.127
• “Title notes and contracts of sale pertaining to the crime of false pretenses pertaining to Lot 13T.”128
• “Child pornography.”129
• “Documents,photographs, and instrumentalities” constituting harassment and threats.130
• “Monopoly money” and “maps of Churchill County” (Monopoly money was found near the body of the murder victim in Churchill County, Nevada).131
In contrast, the following descriptions of documents were plainly insufficient because they contained absolutely no limiting criteria:
• All financial records.132
• All medical records.133
• Any and all records and paraphernalia pertaining to [defendant’s] business.134
Note that a description that is limited only by reference to a broadly-worded criminal statute may not suffice. Thus, affiants who restrict the seizure of documents to general crimes should describe the crime or the manner in which it was carried out;135 e.g., affidavit provided details of defendant’s illegal kickbacks to physicians,136 the affidavit “described the extortion scheme in detail, including that [the suspect] possessed a computer-generated database and communicated with Paycom over email.”137
ALL DOCUMENTS: “PERMEATED WITH FRAUD
There is a long-standing exception to the specificity requirement for business records when the affiant establishes probable cause to believe that the enterprise was so corrupt—so “permeated with fraud”— that all, or substantially all, of its records would likely constitute evidence of a crime.138 As the Ninth Circuit explained in United States v. Kow:
A generalized seizure of business documents may be justified if the government establishes probable cause to believe that the entire business is merely a scheme to defraud or that all of the business’s records are likely to evidence criminal activity.139
For example, in People v. Hepner 140 the California Court of Appeal concluded that authorization to seize all files in a doctor’s office was justified under the “permeated with fraud” rule because the affidavit demonstrated that about 90% of his files constituted evidence of insurance fraud. Similarly, in a case involving a precious metals investment scam, U.S. v. Bentley, the Fourth Circuit upheld a search for “21 categories of documents that collectively covered every business document” on the premises because, said the court, “This is the rare case in which even a warrant stating ‘Take every piece of paper related to the business’ would have been sufficient. [The business] was fraudulent through and through. Every transaction was potential evidence of that fraud.”141
A “permeated with fraud” warrant must not, however, authorize the seizure of all documents if it is reasonably possible to isolate those documents that constitute evidence of the crime.142 For example, if the fraud pertained only to a certain product or occurred only during a certain time period, the warrant should ordinarily authorize a search for documents pertaining only to that product or that period. Similarly, the Ninth Circuit pointed out in Solid State Devices, Inc. v. U.S. that, “[w]here a business appears to be engaged in some legitimate activity, this Court has required a more substantial showing of pervasive fraud.”143
Finally, it should be noted that the “permeated with fraud” doctrine may also be applied to searches of homes, but the required level of proof of widespread fraud may be greater.144
COMPLEX PAPER PUZZLE CASES: The courts may ease the requirement for a particular description of documents in cases where a detailed description is impossible because (1) the crime under investigation was a complex scheme that could only be proved by linking many bits of documentary evidence, and (2) officers described the documents as best they could.145 As the California Supreme Court observed, “In a complex case resting upon the piecing together of many bits of evidence, the warrant properly may be more generalized than would be the case in a more simplified case resting upon more direct evidence.”146
For example, in a real estate fraud case, Andresen v. Maryland, the United States Supreme Court ruled that a warrant to search a lawyer’s office for an array of documents was sufficiently particular because, said the Court:
Like a jigsaw puzzle, the whole picture of petitioner’s false-pretense scheme could be shown only by placing in the proper place the many pieces of evidence that, taken singly, would show comparatively little.147
The Court added that, when officers have probable cause to search for large numbers of documents “[t]he complexity of an illegal scheme may not be used as a shield to avoid detection.”
Indicia
When a warrant authorizes a search for evidence which, if found, would incriminate the people who own or control the home or business that was searched, affiants will almost always seek permission to search for and seize documents and other things that tend to identify these people. Authorization to search for such things—commonly known as “indicia” or “evidence of dominion and control”—is especially apt to be granted when the primary objective of the warrant is to search for drugs, weapons, child pornography, stolen property, or other fruits or instrumentalities of the crime under investigation.
It is true, of course, that authorization to search for indicia may significantly expand the scope of the search.148 Nevertheless, the additional intrusion is almost always deemed justified by the overriding need for proof of control.149
The problem with indicia is that, while officers can be reasonably certain that it will be found on the premises,150 they can never know for sure what form it will take. Consequently, the courts permit a description of the types of things that tend to establish dominion and control, such as the following:
• Delivered mail
• Bills and receipts
• Bail contracts and other legal documents
• Keys to cars, safe deposit boxes, and post office boxes
• Photographs
• Answering machine tapes 151
Note, however, that a description must not be so broad as to permit the seizure of documents that do not establish ownership or control; e.g., “All papers bearing the [suspect’s] name.”
In the next -, we will continue our discussion of search warrants by examining the various special procedures that may be employed if approved by the issuing judge. These include night and no-knock entry, the sealing of warrants, contingent and out-of- county warrant service, and searches by special masters. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.1%3A_Search_Warrants.txt |
Adapt yourself to changing circumstances.
— Chinese proverb
There is perhaps no profession that is more susceptible to changing circumstances than law enforcement. Which means that law enforcement officers must know how to adapt. One task in which adaptability is especially important (although frequently overlooked) is the writing of search warrants and affidavits. That is because every search warrant must be customized to fit the unique circumstances of the crime under investigation, the place being searched, the people who live or work in the location, the nature of the evidence being sought, and any difficulties that the search team might encounter.
For instance, officers may have well-founded concerns about their safety or evidence destruction that make it necessary to execute the warrant late at night, or to make a no-knock entry. Officers might also need to keep the contents of the affidavit secret to protect the identity of an informant or to prevent the disclosure of confidential information. Although less common, it is sometimes necessary to obtain a covert warrant or an anticipatory warrant, or a warrant to search something in another county or state, or a warrant to search the confidential files of a lawyer or physician.
All of these things are doable. But because they add to the intrusiveness of the search, they must be authorized by the judge who issues the warrant. And to obtain authorization, officers must know exactly what information judges require and how it must be presented.
Before we discuss these requirements, it should be noted that we have incorporated these and other special procedures into new search warrant forms that officers and prosecutors can download from our website. The address is: a link to the Alameda County District Attorney's website for law enforcement officers and prosecutors. (click on Publications). To receive copies via email in Microsoft Word format, send a request from a departmental email address to [email protected].
Night Service
Officers are ordinarily prohibited from executing warrants between the hours of 10 P.M. and 7 A.M. That is because late night entries are “particularly intrusive,” 1 especially since officers may need to make a forcible entry if, as is often the case, the occupants are asleep and are thus unable to promptly respond to the officers’ announcement. Still, the courts understand there are situations in which the added intrusiveness of night service is offset by other circumstances, usually the need to prevent the destruction of evidence or to protect the search team from violence by catching the occupants by surprise. For this reason, California law permits judges to authorize an entry at any hour of the day or night if there is “good cause.” 2
WHAT IS GOOD CAUSE”? Good cause exists if there is reason to believe that (1) some or all of the evidence on the premises would be destroyed or removed before 7 A.M., (2) night service is necessary for the safety of the search team or others,3 or (3) there is some other “factual basis for a prudent conclusion that the greater intrusiveness of a nighttime search is justified.”4 Like probable cause, good cause must be based on facts contained in the affidavit, or at least reasonable inferences from the facts.5 “[T]he test to be applied,” said the Court of Appeal, “is whether the affidavit read as a whole in a common sense manner reasonably supports a finding that such service will best serve the interests of justice.” 6
Because specific facts are required, good cause to believe that evidence would be destroyed or removed cannot be based on generalizations or unsupported allegations. For example, the courts have rejected arguments that good cause existed merely because the affiant said “the property sought will be disposed of or become nonexistent through sale or transfer to other persons,”7 or because “drug distributors often utilize the cover of darkness to conceal their transportation and handling of contraband,”8 or because the warrant authorized a search for evidence (such as drugs) that can be quickly sold or consumed.9 Accordingly, the court in People v. Mardian ruled that “an affiant’s averment that in his experience (generally) particular types of contraband are easily disposed of does not, in itself, constitute a sufficient showing for the necessity of a nighttime search.”10 The question, then, is what types of circumstances will suffice? In the case of evidence destruction, the following have been deemed sufficient:
• The suspects were selling drugs or stolen property from the residence at night.11
• The suspect had become aware that he was about to be arrested or that a search of his home was imminent, and it was therefore reasonably likely that he would immediately try to move or destroy the evidence.12
• The suspect was planning to vacate the premises early the next morning.13
• Stolen food, liquor, and cigarettes were consumed at a party in the residence the night before the warrant was executed.14
• The suspect had been released on bail in the early evening, the evidence in his house was “small in size and easily disposed of,” and the only way to keep him from destroying it would have been to assign “police resources in an all night vigil.”15
• The warrant authorized a search for valuable stolen property which the suspects had the ability and motive to quickly sell or abandon.16
As for officer safety, good cause must also be based on facts, not unsupported assertions. As the Court of Appeal explained, “[A]llegations in an affidavit with respect to safety of officers must inform the magistrate of specific facts showing why nighttime service would lessen a possibility of violent confrontation, e.g., that the particular defendant is prepared to use deadly force against officers executing the warrant.”17 Thus, in Rodriguez v. Superior Court the court ruled that good cause was not shown based merely on a statement that “any time you got people dealing in drugs there’s always a danger of being shot or hurt.”18
One other thing about night service: If officers enter before 10 P.M. they do not need authorization to continue the search after 10 P.M.19
HOW TO OBTAIN AUTHORIZATION: There are essentially four things the affiant must do to obtain authorization for night service:
1. STATE THE FACTS: The affiant must set forth the facts upon which “good cause” is based. Although the affidavit need not contain a separate section for this purpose, it is usually helpful to the judge; e.g., For the following reasons, I hereby request authorization to execute this warrant at any hour of the day or night . . .20
2. NOTIFY JUDGE: When submitting the affidavit to the judge, the affiant should notify him or her that he is requesting night service authorization based on facts contained in the affidavit.
3. JUDGE REVIEWS: As the judge reads the affidavit looking for probable cause, he or she will also look for facts that tend to establish good cause for night service.
4. AUTHORIZATION GIVEN: If the judge finds that good cause exists, he or she will authorize night service on the face of the warrant,21 usually by checking an authorization box or by inserting words such as the following: Good cause having been demonstrated, this warrant may be executed at any hour of the day or night.
No-Knock Warrants
[Violent knocks on the front door]
“Police with a search warrant! Open the door or we’ll kick it in.”
Blanca ran into the bathroom and emptied a glassine envelope containing cocaine into the swirling bowl.
“Is that everything?” he said. “I think so,” she said.
That was fiction. It was a scene from the novel To Live and Die in L.A. But similar scenes are played out every day in real life when officers knock, give notice, and wait for a “reasonable” amount of time before making a forcible entry. Because this delay provides the occupants with the time they need to destroy evidence or arm themselves, the knocknotice requirement has been a continuing source of friction between the courts and law enforcement. As the Court of Appeal observed:
[A]lthough one purpose of the [knock-notice] requirement is to prevent startled occupants from using violence against unannounced intruders, the delay caused by the statute might give a forewarned occupant exactly the opportunity necessary to arm himself, causing injury to officers and bystanders. . . . Since one has no right to deny entry to the holder of a search warrant in any event, critics ask, what public policy requires that entry be delayed while police engage in meaningless formalities?22
While it is debatable whether the knock-notice requirements are “meaningless,” we are concerned here with explaining how officers can, when necessary, obtain authorization to enter without giving notice.23
A judge who issues a search warrant may authorize a no-knock entry if there was “sufficient cause”24 or “reasonable grounds”. As the United States Supreme Court explained:
When a warrant applicant gives reasonable grounds to expect futility or to suspect that one or another such exigency already exists or will arise instantly upon knocking, a magistrate judge is acting within the Constitution to authorize a “no-knock” entry.25
WHAT ARE REASONABLE GROUNDS”?
Reasonable grounds for a no-knock warrant exist if the affidavit establishes reasonable suspicion to believe that giving notice would (1) be used by the occupants to arm themselves or otherwise engage in violent resistance, (2) be used by the occupants to destroy evidence, or (3) be futile.26
Like good cause for night service, grounds for noknock authorization must be based on facts, not unsupported conclusions or vague generalizations. Thus, in Richards v. Wisconsin 27 the United States Supreme Court ruled that an affidavit for a warrant to search a drug house was insufficient because it was based solely on the generalization that drugs can be easily destroyed. In contrast, the following circumstances have been deemed adequate:
• The suspect had a history of attempting to destroy evidence, including a “penchant for flushing toilets even when nature did not call.”28
• The suspect told an informant that, if he knew the police “were around,” he would destroy the drugs he was selling and that “he would not get caught again with the evidence.”29
• The premises, which contained a “large amount” of crack, were protected by a steel door.30
• The house was a “virtual fortress.”31
• The house “was equipped with security cameras and flood lights.32
• The suspect displayed a firearm during previous drug sales and had “exhibited abnormal and unpredictable behavior—specifically, answering the door wearing only a pair of socks— while wielding a chambered semi-automatic pistol in a threatening manner.”33
• The suspect’s rap sheet showed “assaultive” behavior in the past, possession of guns, and a prior altercation with an officer.34
PROCEDURE FOR OBTAINING AUTHORIZATION
The usual procedure for obtaining a no-knock warrant is as follows:
1. SET FORTH THE FACTS: The affidavit must include the facts upon which the request is made. Although it need not contain a separate section for this purpose, it will be helpful to the judge; e.g., I hereby request authorization for a noknock entry for the following reasons . . .
2. NOTIFY JUDGE: When submitting the affidavit to the judge, the affiant should notify him or her that he is requesting no-knock authorization.
3. JUDGE REVIEWS: As the judge reads the affidavit looking for probable cause, he or she will also look for facts establishing grounds for a noknock entry.
4. AUTHORIZATION GIVEN: If the judge determines that grounds for a no-knock warrant exist, he or she will authorize a no-knock entry on the face of the warrant; e.g., Good cause having been demonstrated in the affidavit herein, the officers who execute this warrant are authorized to make a forcible entry without giving notice unless a change in circumstances negates the need for non-compliance.
Two other things should be noted about no-knock warrants. First, although officers are not required to re-evaluate the circumstances before entering, they are not permitted to make a no-knock entry if, before entering, they become aware of circumstances that eliminated the need for it.35 Second, if the judge refused to issue a no-knock warrant, officers may nevertheless make an unannounced entry if, upon arrival, they become aware of circumstances that constituted grounds to do so.36
Sealing Orders
Search warrants, including their supporting affidavits and any incorporated documents, become a public record when they are returned to the court or, if not executed, ten days after they were issued.37 But because public disclosure may have serious adverse consequences, the affiant may apply for a sealing order which would require that all or part of the affidavit be kept confidential until further order of the court.38
GROUNDS FOR SEALING ORDERS
In most cases, sealing orders are issued for either of the following reasons:
1. PROTECT INFORMANT’S IDENTITY: If the warrant is based wholly or in part on information from a confidential informant, the judge may seal the parts of the affidavit that would reveal or tend to reveal his identity.39
2. PROTECT “OFFICIAL INFORMATION”: An affidavit may be sealed if it tends to disclose “official information,” which is defined as confidential information whose disclosure would not be in the public interest; e.g., information obtained in the course of an ongoing criminal investigation; information that would tend to reveal the identity of an undercover officer, a citizen informant, a confidential surveillance site, or the secret location of VIN numbers.40
PROCEDURE
To obtain a sealing order, the affiant must do the following:
1. DETERMINE SCOPE OF ORDER: The first step is to determine whether it is necessary to request the sealing of only certain information, certain documents, or everything.41
2. SEGREGATE CONFIDENTIAL INFORMATION: If the affiant is requesting that only part of the affidavit be sealed, he will present the judge with two affidavits for review: one containing information that may be disclosed; the other containing information that would be subject to the sealing order.42 The latter affidavit should be clearly identified by assigning it an exhibit number or letter, then writing that number or letter in a conspicuous place at the top of the document; e.g., Exhibit A.
3. REQUEST ORDER: The affiant should state in the affidavit that he is seeking a sealing order; e.g., For the following reasons, I am hereby requesting that Exhibit A be sealed pending further order of the court . . .
4. PROVING CONFIDENTIALITY: The affiant must explain why the sealing is reasonably necessary. To prove that the sealed information would tend to disclose the identity of a confidential informant, the affiant should explain why the informant or his family would be in danger if his identity was revealed. To prove that sealed information is covered under the “official information” privilege, the affiant should set forth facts demonstrating that the information was “acquired in confidence by a public employee in the course of his or her duty and not open, or officially disclosed, to the public prior to the time the claim of privilege is made.”43
5. JUDGE ISSUES ORDER: If the affiant’s request is granted, the judge will sign the sealing order. Although the order may be included in the warrant, it is better to incorporate it into a separate document so that it is not disclosed to the people who are served with the warrant. A sealing order is available on our website.
6. WHERE SEALED DOCUMENTS MUST BE KEPT: All sealed documents must be retained by the court, unless the judge determines that court security is inadequate.44 In such cases, the documents may be retained by the affiant if he submits proof that the security precautions within his agency are sufficient, and that his agency has established procedures to ensure that the sealed affidavit is retained for ten years after final disposition of noncapital cases, and permanently in capital cases.45
Nondisclosure Orders
Officers will frequently utilize a search warrant to obtain the records of a customer of a financial institution, phone company, or provider of an email or internet service. If, as in most cases, they do not want the customer to learn about it, they may ask the issuing judge for a temporary nondisclosure order. Such an order may ordinarily be issued if the affiant demonstrates that disclosure would seriously jeopardize an ongoing investigation or endanger the life of any person.46
A nondisclosure order should appear on the warrant to help ensure that the people who are served with the warrant will be aware of it. The following is an example of such an order: Pending further order of this court, the employees and agents of the entity served with the warrant are hereby ordered not to disclose information to any person that would reveal, or tend to reveal, the contents of this warrant or the fact that it was issued.
Out-of-Jurisdiction Warrants
It is not unusual for officers to develop probable cause to believe that evidence of the crime they are investigating is located in another county or state. If they need a warrant to obtain it, the question arises: Can the warrant be issued by a judge in the officers’ county? Or must it be issued by a judge in the county or state in which the evidence is located? The rules pertaining to out-of-jurisdiction warrants are as follows.
OUT-OF-COUNTY WARRANTS: A judge in California may issue a warrant to search a person, place, or thing located in any county in the state if the affidavit establishes probable cause to believe that the evidence listed in the warrant pertains to a crime that was committed in the county in which the judge sits. As the California Supreme Court explained, “[A] magistrate has jurisdiction to issue an out-of-county warrant when he has probable cause to believe that the evidence sought relates to a crime committed within his county and thus pertains to a present or future prosecution in that county.”47
For example, in People v. Easley 48 officers who were investigating a double murder in Modesto (Stanislaus County) obtained a warrant from a local judge to search for evidence of the crimes in Easley’s homes and cars in Fresno County. In ruling that the judge had the authority to issue the warrant, the California Supreme Court said:
[T]he search warrant sought evidence relating to two homicides committed in Stanislaus County. The magistrate had probable cause to believe that evidence relevant to those crimes might be found in defendant’s residences and automobiles. He therefore had jurisdiction to issue a warrant for an out-of-county search for that evidence.
Not surprisingly, out-of-county search warrants are especially common in drug trafficking cases because sellers seldom restrict their operations to a single county. Thus, in such cases a warrant may be issued by a judge in any country in which some illegal act pertaining to the enterprise was committed. For example in People v. Fleming 49 an undercover Santa Barbara County sheriff ’s deputy bought cocaine from Bryn Martin in Santa Barbara. The deputy later learned that Martin’s supplier was Scott Fleming, who lived in Los Angeles County. The deputy then obtained a warrant from a Santa Barbara judge to search Fleming’s house, and the search netted drugs and sales paraphernalia.
Fleming, who was tried and convicted in Santa Barbara County, argued that the evidence should have been suppressed, claiming that the judge lacked the authority to issue the warrant. But the California Supreme Court disagreed, pointing out that because both sales were negotiated in Santa Barbara County, and because a person can be prosecuted in any county in which “some act of a continuing crime occurs,” the judge “acted within his jurisdiction in issuing the warrant in question.”
Two procedural matters. First, an out-of-county warrant must be directed to peace officers employed in the issuing judge’s county.50 For example, a warrant to conduct a search in Santa Clara County issued by a judge in Alameda County should be headed, The People of the State of California to any peace officer in Alameda County. Second, although the warrant may be executed by officers in the issuing judge’s county, it is standard practice to notify and request assistance from officers in whose jurisdiction the search will occur.51
OUT-OF-STATE WARRANTS
California judges do not have the authority to issue warrants to search a person, place, or thing located in another state.52 Consequently, officers who need an out-of-state warrant must either travel to the other state and apply for it themselves or, more commonly, request assistance from an officer in that state. Because the officers who are requesting assistance should complete as much of the paperwork as possible, they should ordinarily do the following:
1. Write an affidavit establishing probable cause for the search and sign it under penalty of perjury. (As discussed below, this affidavit will become an attachment to the affidavit signed by the out-of-state officer.)
2. Write an affidavit for the out-of-state officer’s signature in which the out-of-state officer simply states that he is incorporating the California officer’s affidavit, and that it was submitted to him by a California officer; e.g., Attached hereto and incorporated by reference is the affidavit of [name of California officer] who is a law enforcement officer employed by the [name of California officer’s agency] in the State of California. I declare under penalty of perjury that the foregoing is true. (The reason the out-of-state officer must not sign the affidavit establishing probable cause is that will have no personal knowledge of the facts upon which probable cause was based.)
3. Attach the California officer’s probable-cause affidavit to the out-of-state officer’s unsigned affidavit.
4. In a separate document, write the following:
1. Descriptions of the person, place, or thing to be searched.
2. Descriptions of the evidence to be seized.
3. A suggested court order pertaining to the disposition of seized evidence; e.g., All evidence seized pursuant to this warrant shall be retained by [name of California officer] of the [name of California officer’s agency] in California. Such evidence may thereafter be transferred to the possession of a court of competent jurisdiction in California if it is found to be admissible in a court proceeding.
5. Email, fax, or mail all of these documents to the out-of-state officer.
Upon receipt of these documents, the out-of-state officer should do the following:
1. Prepare a search warrant in accordance with local rules and procedures using the descriptions provided by the California officer, and incorporating the order that all seized evidence be transferred to the California officer.
2. Take the search warrant and affidavit (to which the California officer’s affidavit has been attached) to a local judge.
3. In the judge’s presence, sign the affidavit in which he swears that the incorporated and attached affidavit was submitted to him by a California law enforcement officer.
If the judge issues the warrant, it will be executed by officers in whose jurisdiction the search will occur. Those officers will then give or send the evidence to the California authorities.
Special Master Procedure
A search for documents in the office of a lawyer, physician, or psychotherapist (hereinafter “professional”) is touchy because these papers often contain information that is privileged under the law. Still, officers can obtain a warrant to search for them if the search is conducted in accordance with a protocol—known as the “special master procedure”—that was designed to ensure that privileged communications remain confidential.53
Before going further, it should be noted that the law in this area has changed. In the past, officers in California were required to implement this procedure only if the suspect was a client or patient of the professional; i.e., the professional was not the suspect. In 2001, however, the California Supreme Court essentially ruled that this procedure must be employed in all searches of patient or client files because, even if the professional was the suspect, he or his custodian of records is ethically obligated to assert the confidentiality privilege as to all files that officers intend to read.54
As we will now discuss, under the mandated procedure the files must be searched by an independent attorney, called a “special master,” who is trained in determining what materials are privileged. Accordingly, officers will ordinarily utilize the following protocol:
1. AFFIANT REQUESTS SPECIAL MASTER: The affiant will state in the affidavit that he believes the search will require the appointment of a special master; e.g., It appears that the requested search will implicate the confidentially of privileged communications. Accordingly, pursuant to Penal Code section 1524(c) I request that a special master be appointed to conduct the search.
2. SPECIAL MASTER APPOINTED: If the warrant is issued, the judge will appoint a special master whom the judge will select from a list of qualified attorneys compiled by the State Bar.
3. SPECIAL MASTER EXECUTES WARRANT: Officers will accompany the special master to the place to be searched. When practical, the warrant must be executed during regular business hours. Upon arrival, the special master will provide the professional (or custodian of records) with a copy of the warrant so that the professional will know exactly what documents the special master is authorized to seize. The special master must then give the professional an opportunity to voluntarily furnish the described documents. If he fails or refuses, the special master—not the officers—will conduct the search while the officers stand by.
4. PRIVILEGED DOCUMENTS SEALED: If the special master finds or is given documents that are described in the warrant, he will determine whether they are confidential. If not confidential, he may give them to the officers. But if they appear to be confidential, or if the professional claims they are, he must (a) seal them (e.g., put them in a sealed container); (b) contact the clerk for the issuing judge and obtain a date and time for a hearing to determine whether any sealed documents are privileged; and (c) notify the professional and the officers of the date, time, and location of the hearing.55
Note that if a hearing is scheduled, officers should immediately notify their district attorney’s office or city attorney’s office so that a prosecutor can, if necessary, attend and represent the officers and their interests.
Search Conducted By An Expert
While most searches are conducted by officers, there are situations in which it is impossible or extremely difficult for officers to do so because the evidence is such that it can best be identified by a person with certain expertise. When this happens the affiant may seek authorization to have an expert in such matters accompany the officers and conduct the search himself.56 For example, in People v. Superior Court (Moore) 57 officers were investigating an attempted theft of trade secrets from Intel and, in the course of the investigation, they sought a warrant to search a suspect’s business for several items that were highly technical in nature; e.g., “magnetic data base tape containing Intel Mask data or facsimile for product No. 2147 4K Ram.” The affiant realized that “he could not identify the property due to its technical nature without expert assistance,” so he requested such assistance in the affidavit. The request was granted.
As the Court of Appeal explained, when the warrant was executed “none of the officers present actually did any searching, since none of them knew what the items described in the warrant looked like. Rather, at the direction of the officer in charge, they stood and watched while the experts searched”; and when an expert found any of the listed evidence, he would notify the officers who would then seize it. The court summarily ruled that such a procedure was proper.
Note that if the search will be conducted by officers, they do not need authorization to have an expert or other civilian accompany them and watch. And if the civilian sees any seizable property, he will notify the officers who will take it; e.g., burglary victim identifies stolen property.58
Anticipatory Search Warrants
Most search warrants are issued because officers have probable cause to believe that evidence of a crime is presently located in the place to be searched. There is, however, another type of warrant—known as an “anticipatory” or “contingent” warrant—that is issued before the evidence has arrived there. Specifically, an anticipatory search warrant may be issued when officers have probable cause to believe that the evidence—although not currently on the premises— will be there when a “triggering event” occurs.59 In other words, the occurrence of the triggering event demonstrates that the evidence has arrived and, thus, probable cause now exists. As the Fourth Circuit put it, the triggering event “becomes the final piece of evidence needed to establish probable cause.”60
The courts permit anticipatory warrants because, as the court noted in U.S. v. Hugoboom, without them officers “would have to wait until the triggering event occurred; then, if time did not permit a warrant application, they would have to forego a legitimate search, or, more likely, simply conduct the search (justified by exigent circumstances) without any warrant at all.”61
Although there are no restrictions on the types of evidence that may be sought by means of an anticipatory warrant, most are used in conjunction with controlled deliveries of drugs or other contraband.62 As the First Circuit observed:
Anticipatory search warrants are peculiar to property in transit. Such warrants provide a solution to a dilemma that has long vexed law enforcement agencies: whether, on the one hand, to allow the delivery of contraband to be completed before obtaining a search warrant, thus risking the destruction or disbursement of evidence in the ensuring interval, or, on the other hand, seizing the contraband on its arrival without a warrant, thus risking suppression.63
Procedure
The procedure for obtaining an anticipatory warrant is essentially the same as that for a conventional warrant, except that the affidavit must also contain the following:
1. DESCRIPTION OF TRIGGERING EVENT: The affidavit must contain an “explicit, clear, and narrowly drawn” description of the triggering event;64 i.e., the description should be “both ascertainable and preordained” so as to “restrict the officers’ discretion in detecting the occurrence of the event to almost ministerial proportions.”65
2. TRIGGERING EVENT WILL OCCUR: The affidavit must establish probable cause to believe the triggering event will, in fact, occur; and that it will occur before the warrant expires.66
3. PROBABLE CAUSE WILL EXIST: Finally, it must appear from the affidavit that the occurrence of the triggering event will give rise to probable cause to search the premises.67
WHERE THE DESCRIPTION MUST APPEAR
Although the United States Supreme Court has ruled that the triggering event need not be described on the face of the warrant,68 the warrant should at least indicate that the judge determined that it may be executed when the triggering event occurs, and not, as in conventional warrants, on any day before the warrant expires. Consequently, language such as the following should be added to the warrant: Having determined that probable cause for this search will result when the triggering event described in the supporting affidavit occurs; and, furthermore, that there is probable cause to believe that this triggering event will occur; it is ordered that this warrant shall be executed without undue delay when the triggering event occurs.
CONTROLLED DELIVERIES
As noted, most of the cases in which anticipatory warrants have been utilized involved controlled deliveries of drugs or other contraband, usually to the suspect’s home. In these situations, the triggering event will commonly consist of a delivery of the evidence directly to the suspect’s residence by the Postal Service, a delivery company such as UPS or FedEx, an undercover officer, or an informant under the supervision of officers.69 Probable cause may also be found when there was strong circumstantial evidence that the contraband would be delivered to the premises; e.g., undercover officers had previously purchased drugs there,70 or if intercepted contraband consisted of a quantity of drugs that was “too great an amount to be sent on a whim.”71
THE “SURE AND IRREVERSIBLE COURSE RULE
There is one other issue that must be addressed. Some courts have ruled that, when the triggering event is a controlled delivery, it is not sufficient that there is probable cause to believe the triggering event will occur; i.e., that there is a fair probability that the contraband will be taken to the place to be searched. Instead, it must appear that the contraband was on a “sure and irreversible course” to the location. The theoretical justification for this “requirement” is, according to the Seventh Circuit, “to prevent law enforcement authorities or third parties from delivering or causing to be delivered contraband to a residence to create probable cause to search the premises where it otherwise would not exist.”72
Based on the complete absence of any proof (or even a suggestion) that anyone had actually engaged in such blatantly illegal conduct, it appears the court’s concern was based on nothing more than its overwrought imagination. Moreover, the “sure course” requirement is plainly contrary to the Supreme Court’s ruling that only probable cause is required; i.e., that grounds for an anticipatory warrant will exist if “it is now probable that contraband, evidence of a crime, or a fugitive will be on the described premises when the warrant is executed.”73 It is therefore likely that, because the “sure and irreversible course” requirement establishes a standard higher than probable cause, it is a nullity.74
Furthermore, there has never been a need for a “sure course” requirement because the cases in which it has been applied to invalidate a search could have been decided without it on grounds that the affidavit simply failed to establish probable cause to believe the evidence would be taken to the place to be searched. In fact, almost all cases in which the courts have invalidated searches based on a “sure course” transgression have involved controlled deliveries in which (1) the evidence was initially delivered to a location other than the suspect’s home (e.g., a post office box), or was intercepted before it reached the suspect’s home; (2) the affidavit failed to establish probable cause to believe it would be taken to the suspect’s home; and (3) there was no independent probable cause linking the suspect’s home to the criminal activity under investigation.75 Thus, in these cases the affidavits would have failed irrespective of the “sure course” deficiency because they did not establish probable cause to believe the evidence would be taken to the place to be searched. The case of U.S. v. Rowland 76 demonstrates the uselessness of the “sure course” concoction. In Rowland, postal inspectors intercepted child pornography that had been mailed to Rowland’s post office box. So they obtained an anticipatory warrant that authorized a search of Rowland’s home when the package was picked up and brought inside. The court ruled, however, that the warrant was invalid, not because of a “sure course” violation, but because the affidavit simply lacked facts that established a fair probability that the evidence would, in fact, be taken to Rowland’s house. As the court pointed out, “The affidavit stated: ‘It is anticipated that [Rowland], after picking up the tapes from the post office box, will go to his place of employment and after work to his residence.’ The affidavit contained no information suggesting that Rowland had previously transported contraband from his private post office box to his home or that he had previously stored contraband at his home. Nor, did the affidavit provide any facts linking Rowland’s residence to suspected illegal activity.”
Warrants to Search Computers
Although computer searches are notoriously complex, the procedure for obtaining a warrant to search a computer is not much different than any other warrant. In fact, there are only three significant differences: (1) the manner of describing the hardware to be searched and the data to be seized (we covered those subjects in the Spring 2011 edition), (2) obtaining authorization for an off-site search, and (3) incorporating search protocols.
IS AN OFF-SITE SEARCH NECESSARY?
As a practical matter, it will almost always be necessary to conduct a computer search off-site unless officers plan to conduct only a superficial examination; e.g., they will be trying to locate the listed information by conducting a simple word search or merely looking at the names of directories and files. As the federal courts have observed, because it is “no easy task to search a well-laden hard drive,”77 the “practical realities of computer investigations preclude on-site searches.” 78
IS OFF-SITE AUTHORIZATION NECESSARY? Although
some courts have ruled that officers do not need express authorization to conduct the search off site,79 the better practice is to seek it. This is especially so when, as is usually the case, officers know when they apply for the warrant that an off-site search may be necessary.
HOW TO OBTAIN AUTHORIZATION: To obtain authorization for an off-site search, the affiant must explain why it is necessary.80 Here’s an example:
Request for Off-Site Search Authorization: For the following reasons, I request authorization to remove the listed computers and computer-related equipment from the premises and search them at a secure location:
1. The amount of data that may be stored digitally is enormous, and I do not know the number or size of the hard drives and removable storage devices on the premises that will have to be searched pursuant to this warrant.
2. The listed data may be located anywhere on the hard drives and removable storage devices, including hidden files, program files, and “deleted” files that have not been overwritten.
3. The data may have been encrypted, it may be inaccessible without a password, and it may be protected by self-destruct programming, all of which will take time to detect and bypass.
4. Because data stored on computers can be easily destroyed or altered, either intentionally or accidentally, the search must be conducted carefully and in a secure environment.
5. To prevent alteration of data and to ensure the integrity of the search, we plan to make clones of all drives and devices, then search the clones; this, too, will take time and special equipment.
6. A lengthy search at the scene may pose a severe hardship on all people who [live][work] there, as it would require the presence of law enforcement officers to secure the premises while the search is being conducted.
The affiant should then add some language to the proposed search warrant that would authorize an off-site search; e.g., Good cause having been established in the affidavit filed herein, the officers who execute this warrant are authorized to remove the computers and computer-related equipment listed in this warrant and search them at a secure location.
One other thing: If the warrant was executed within ten days after it was issued, officers do not need specific authorization to continue searching after the warrant expires.81 Officers must, however, conduct the search diligently.
UTILIZING PROTOCOLS: If officers expect to find seizable files intermingled with non-seizable files, they may—but are not required to 82 —seek authorization to conduct the search pursuant to a protocol. Generally speaking, a protocol sets forth the manner in which the search must be conducted so as to minimize examinations and seizures of files that do not constitute evidence. For example, a protocol might require “an analysis of the file structure, next looking for suspicious file folders, then looking for files and types of files most likely to contain the objects of the search by doing keyword searches.”83
Covert Search Warrants
Covert search warrants, commonly known as “sneak and peek” warrants, authorize officers to enter a home or business when no one is present, search for the listed evidence, then depart—taking nothing and, if all goes well, leaving no clue that they were there. Covert warrants are rarely necessary, but they may be useful if officers need to know whether evidence or some other items are on the premises, but the investigation is continuing and they do not want to alert the suspects that investigators are closing in. Covert warrants may also be helpful to identify the co-conspirators in a criminal enterprise before officers start making arrests.84
THE NOTICE REQUIREMENT: The main objection to covert warrants is that the people whose homes and offices are searched are not immediately notified that a search has occurred. But the United States Supreme Court has described this objection as “frivolous,” pointing out that instant notification is not a constitutional requirement, as demonstrated by the delayed-notice provisions in the federal wiretap law.85 Still, because notice must be given eventually, some federal courts have required that the occupants of the premise be given notice of the search within seven days of its execution, although extensions may be granted.86 Note that the Ninth Circuit has ruled that a judge may authorize a delay of over seven days if the affiant makes a “strong showing of necessity.”87 While California courts have not yet ruled on the legality of this procedure, it seems to provide a reasonable solution to the notification concerns.
TO OBTAIN AUTHORIZATION
The following procedure, adapted by the federal courts, should suffice to obtain a covert entry warrant in California:
1. DEMONSTRATE REASONABLE NECESSITY: In addition to establishing probable cause to search, the affidavit must demonstrate that a covert search is reasonably necessary.88 Note that reasonable necessity does not exist merely because a covert search would facilitate the investigation or would otherwise be helpful to officers.89
2. ADD SPECIAL INSTRUCTIONS: Instructions, such as the following, should be added to the warrant: The evidence described in this warrant shall not be removed from the premises. An inventory of all evidence on the premises shall be prepared showing its location when discovered. Said evidence shall also be photographed or videotaped to show its location. Compliance with the receipt requirement of Penal Code § 1535 is excused until unless an extension is granted by this court. Within two days after this warrant is executed, the following shall be filed with this court: (a) the inventory, and (b) the original or copy of all photographs and/or videotapes.
Steagald Search Warrants
A Steagald warrant is a search warrant that authorizes officers to enter a home, business office, or other structure for the purpose of locating and arresting a person who (1) is the subject of an outstanding arrest warrant, and (2) does not live on the premises. For example, officers would need a Steagald warrant to search for the arrestee in the home of a friend or relative.90 In contrast, only an arrest warrant (a conventional warrant or a Ramey warrant) would be necessary to enter the arrestee’s home to make the arrest.
The reason that officers need a Steagald warrant (or consent or exigent circumstances) to enter a third person’s home is that, otherwise, the homes of virtually everyone who knows the arrestee would be subject to search at any time until the arrestee was taken into custody.
As we will now discuss, a judge may issue a Steagald warrant if the affidavit demonstrates both probable cause to arrest and search.
PROBABLE CAUSE TO ARREST: There are two ways to establish probable cause to arrest:
1. WARRANT OUTSTANDING: If a conventional or Ramey arrest warrant is outstanding, the affiant can simply attach a copy to the affidavit and incorporate it by reference; e.g., Attached hereto and incorporated by reference is a copy of the warrant for the arrest of [name of arrestee]. It is marked Exhibit A.
2. PROBABLE CAUSE: If an arrest warrant has not yet been issued, the affidavit for the Steagald warrant must establish probable cause to arrest, as well as probable cause to search. (In such cases, the Steagald warrant serves as both an arrest and search warrant.)
PROBABLE CAUSE TO SEARCH
There are two ways to establish probable cause to search.
1. ARRESTEE IS INSIDE: Establish probable cause to believe that the arrestee was inside the residence when the warrant was issued and would still be there when the warrant was executed.
2. ANTICIPATORY SEARCH WARRANT: Establish a fair probability that the arrestee would be inside the residence when a “triggering event” occurs (e.g., when officers see the arrestee enter), and that there is probable cause to believe the triggering event will occur; e.g., the arrestee has been staying in the house for a few days.91 The subject of anticipatory search warrants was covered earlier in this article.
Email Search Warrants
While most warrant applications are made by submitting hard copies of the affidavit and warrant to the issuing judge, California law has long permitted officers to seek warrants via telephone and fax. More recently, however, officers were given the added option of obtaining search warrants by email. And because the email procedure is so easy (and the others are so cumbersome), phone and fax warrants are now virtually obsolete.
Before setting forth the email procedure, it is necessary to define two terms that have been added to this area of the law:
Digital signature: The term “digital signature” means “an electronic identifier, created by computer, intended by the party using it to have the same force and effect as the use of a manual signature.” 92
Electronic signature: The term “electronic signature” means “an electronic sound, symbol, or process attached to or logically associated with an electronic record and executed or adopted by a person with the intent to sign the electronic record.”93
The following is the procedure established by California statute that officers must implement to obtain a warrant by email:
1. PREPARE AFFIDAVIT AND WARRANT: Complete the affidavit and search warrant as an email message or in a word processing file that can be attached to an email message.
2. PHONE JUDGE: Notify the on-call judge that an affidavit and search warrant have been prepared for immediate transmission by email.
3. OATH: Before the documents are transmitted, the judge administers the oath to the affiant over the telephone.
4. AFFIANT SIGNS: Having been sworn, the affiant signs the affidavit via digital or electronic signature.
5. AFFIANT TRANSMITS DOCUMENTS: After confirming the judge’s email address, the affiant sends the following by email: (a) the affidavit (including any attachments), and (b) the warrant.
6. CONFIRMATION: The judge confirms that all documents were received and are legible. Missing or illegible documents must be re-transmitted. Affiant confirms that the digital or electronic signature on the affidavit is his.
7. JUDGE READS AFFIDAVIT: The judge determines whether the facts contained in the affidavit and any attachments constitute probable cause.
8. JUDGE ISSUES WARRANT: If the judge determines that probable cause to search exists, he or she will do the following: (a) Sign the warrant digitally or electronically; (b) note the following on the warrant: (i) the date and time it was signed, and (ii) that the affiant’s oath was administered over the telephone; and (c) email the signed warrant to the affiant.
9. AFFIANT ACKNOWLEDGES RECEIPT: The affiant acknowledges that he received the warrant.
10. AFFIANT PRINTS HARD COPY: The affiant prints a hard copy of the warrant.
11. DUPLICATE ORIGINAL CREATED: The judge instructs the affiant over the telephone to write the words “duplicate original” on the hard copy.
12. PROCESS COMPLETE: The duplicate original is a lawful search warrant.94
Warrant Reissuance
A warrant is void if not executed within ten days after it was issued.95 If the warrant becomes void, a judge cannot simply authorize an extension; instead, the affiant must apply for a new warrant, which includes submitting a new affidavit.96 The required procedure is, however, relatively simple.
Specifically, if the information in the original affidavit is still accurate, the affiant can incorporate the original affidavit by reference into the new one—but he must explain why he believes the information is still correct;97 e.g., Affidavit for Reissuance of Search Warrant: On [insert date of first warrant] a warrant (hereinafter Warrant Number One) was issued by [insert name of judge who issued it] authorizing a search of [insert place to be searched]. A copy of the affidavit upon which Warrant Number One was based is attached hereto, incorporated by reference, and marked “Exhibit A”. For the following reasons, Warrant Number One was not executed within 10 days of issuance: [Explain reasons]. I am not aware of any information contained in Exhibit A that is no longer accurate or current. Consequently, I believe that the evidence listed in Warrant Number One is still located at the place to be searched, and I am hereby applying for a second search warrant identical in all material respects to Warrant Number One. I declare under penalty of perjury that the foregoing is true and correct.
If any information in the original affidavit is no longer accurate, it must be deleted. If there have been new developments or circumstances that may have undermined the existence of probable cause, the additional information must be included in the new affidavit.98 If new developments have strengthened probable cause, officers should ordinarily include them in the new affidavit.
Other Special Procedures
RELEASING SEIZED EVIDENCE: When officers seize evidence pursuant to a search warrant, the evidence is technically in the custody and control of the judge who issued the warrant.99 Consequently, the officers cannot transfer possession of the evidence to officers from another agency or any other person unless they have obtained a court order to do so. (We have posted such a court order on our website.) If, however, the property was seized by mistake, officers do not need court authorization to return it to the owner.100
INSPECTION OF DOCUMENTS BY OTHER AGENCY: If officers from another agency want to make copies of documents seized pursuant to a warrant, they should seek an “Order to Examine and Copy Documents Seized by Search Warrant.”101 (We have also posted a form for this purpose on our website.) This order should be supported by an affidavit establishing probable cause to believe the documents are evidence of a crime that the outside agency is investigating. The order should, if possible, be issued by the judge who issued the warrant.102
SUBPOENA DUCES TECUM: Officers have occasionally asked whether they can obtain evidence by means of a subpoena duces tecum instead of a search warrant. Although the subpoena procedure may be quicker, a subpoena duces tecum is not a practical alternative for the following reasons. First, unless the subpoena is issued in conjunction with a criminal investigation conducted by a grand jury,103 it may be issued only if (1) the defendant had already been charged with the crime under investigation, and (2) the officers are seeking evidence pertaining to that crime. Second, a person who is served with a subpoena must deliver the documents to the court— not to officers.104 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.2%3A_Search_Warrants_and_Special_Procedures.txt |
“An officer’s conduct in executing a search [warrant] is subject to the Fourth Amendment’s mandate of reasonableness from the moment of the officer’s entry until the moment of departure.” 1
The execution of a warrant to search a home is, from start to finish, a frightening display of police power. After all, it is nothing less than an armed invasion into the sanctity of the home. And although most people can avoid such unpleasantness by simply not committing any crimes (or at least stop committing them), it is such an extreme intrusion that it is closely and scrupulously regulated by the courts.
These regulations fall into two broad categories. First, there is the basic Fourth Amendment requirement that warrants may be issued only if officers have demonstrated probable cause and have adequately described the place to be searched and the evidence to be seized.
The second requirement, while also based on the Fourth Amendment, is not as well known but it’s just as important: Officers who are executing a warrant must carry out their duties in a reasonable manner.2 As the court said in Hells Angels v. City of San Jose, “The test of what is necessary to execute a warrant effectively is reasonableness.”3
This does not mean there are no absolute rules. On the contrary, as we will discuss, there are lots of them. But because the business of executing search warrants is so unpredictable and dangerous, the courts recognize that officers must be allowed some flexibility in interpreting and applying these rules. Thus, the Supreme Court noted that “it is generally left to the discretion of the executing officers to determine the details of how best to proceed with the performance of a search authorized by warrant.”4
Before we begin, it should be noted that, although many of the legal issues we will discuss pertain to most types of warranted searches, we will focus on the most common and problematic variety: searches of homes, especially searches for illegal drugs and weapons, and also searches for information contained in documents and computers.
When Warrants May Be Executed
While most of the rules on executing search warrants restrict the manner in which officers enter the premises and carry out the search, there are certain rules on when warrants may be executed. By the way, a warrant is “executed” at the point officers enter the premises.5
TIME OF EXECUTION: A search warrant must be executed between the hours of 7 A.M. and 10 P.M. unless the judge authorizes night service, in which case it may be executed at any hour of the day or night.6 Because a warrant is “executed” when officers entered, it is immaterial that they remained on the premises after 10 P.M. to complete the search.7
ENTRY WITHOUT PHYSICAL WARRANT: Officers may execute the warrant when they have been notified that the warrant had been signed by a judge. Thus, they need not wait for the warrant to be brought to the premises.8 However, if the judge made any changes to the warrant that altered the scope or intensity of the search, the officers on the scene must be notified of the changes before they begin the search.9
ENTERING UNOCCUPIED PREMISES: Officers may execute a warrant to search a home even though they knew the residents were not inside.10
WHEN WARRANTS EXPIRE: A search warrant must be executed within 10 days after it was issued. After that, it is void.11 In calculating the 10-day period, do not count the day on which the warrant was issued, although it may be executed on that day.12 Again, because a warrant is “executed” when entry is made, officers who enter within the 10-day window do not need a new warrant if the warrant expires while they were conducting the search.13
This rule also applies if officers mailed or faxed the warrant to a bank or other third-party business. Consequently, the warrant remains valid despite any reasonable delay by employees in assembling the documents and sending them to officers.14
IF PROBABLE CAUSE DISAPPEARS: Even if the warrant had not expired, it automatically becomes void if officers learned that probable cause no longer existed. As the Tenth Circuit explained, “The Fourth Amendment requires probable cause to persist from the issuance of a search warrant to its execution.”15
Entry Procedure
From the perspective of the officers and the occupants of the premises, the initial entry is the most uncertain, stressful, and dangerous operation in the entire process. For that reason, the courts have imposed certain restrictions that are intended to minimize the danger and provide an orderly and efficient transfer of control of the premises from the residents to the officers.16
Knock-notice
To fully comply with the knock-notice rule, officers must do the following before forcibly entering the premises:
1. KNOCK: Knock or otherwise alert the occupants that someone is at the door. This also provides some assurance that the occupants will hear the officers’ announcement.
2. ANNOUNCE AUTHORITY: Announce their authority; e.g. “Police officers!”
3. ANNOUNCE PURPOSE: Announce their purpose; e.g., “Search warrant!”
4. WAIT FOR REFUSAL: Before breaking in, officers must give the occupants an opportunity to admit them peacefully. Thus, officers must not enter until it reasonably appears that the occupants are refusing to admit them.17
Although these requirements (or versions of them) are over 400 years old, 18 they are still generally viewed by officers as a perversion. Particularly, they question why, having a legal right to enter, they must engage in what is arguably a “meaningless formality” that provides the occupants with an opportunity to destroy evidence or arm themselves?19
But there is another view: Without an announcement, the occupants might conclude that their home is being invaded by a burglar, a robber, or a persistent door-to-door salesman—and start shooting. As the California Supreme Court pointed out, “[F]ew actions are as likely to evoke violent response from a householder as unannounced entry by a person whose identity and purpose are unknown to the householder.”20
In an attempt to accommodate these competing interests, the courts have given officers a great deal of leeway in determining if they must comply with the knock-notice requirements and, if so, when and how they must do so.
NO-KNOCK WARRANTS: When officers apply for a search warrant, they can also seek authorization to enter without knocking or making an announcement. As the Supreme Court observed, “The practice of allowing magistrates to issue no-knock warrants seems entirely reasonable when sufficient cause to do so can be demonstrated ahead of time.”21 What is “sufficient cause”? It exists if the affidavit demonstrates reasonable suspicion to believe that compliance with the knock-notice requirements would (1) result in violent resistance from the occupants, (2) result in the destruction of evidence, or (3) be futile.22 Note that, even if the judge authorized a no-knock entry, such authorization terminates automatically if, before entering, the officers became aware of circumstances that eliminated the need for it.23
EXCUSED NONCOMPLIANCE: Even in the judge refused to issue a no-knock warrant, officers may dispense with the knock-and-announce procedure if, upon arrival, they reasonably believed there were circumstances that would have justified a non-knock entry; e.g., destruction of evidence.24
SUBSTANTIAL COMPLIANCE: In some cases the courts have ruled that compliance was unnecessary if it reasonably appeared that someone inside the residence was aware that officers were about to enter, and that their purpose was to execute a search warrant.25
AFFIRMATIVE REFUSALS: Officers may enter without waiting to be refused entry if the occupants said or did something that reasonably indicated they would not admit the officers peacefully, or that they were actually trying to prevent or delay the officers’ entry; e.g., the occupants started running away from the front door,26 an occupant “slammed the door closed,”27 officers heard sounds that suggested “surreptitious movement.”28
IMPLIED REFUSALS: In the absence of an affirmative refusal, a refusal will be implied if the officers were not admitted into the premises within a reasonable time after they announced their authority and purpose.29 In fact, the Ninth Circuit observed that “[t]he refusal of admittance contemplated by the [knocknotice] statute will rarely be affirmative, but will oftentimes be present only by implication.”30
There is, however, no minimum amount of time that must pass before a refusal may be inferred.31 Instead, it depends on the totality of circumstances,32 especially the following:
SIZE AND LAYOUT: Size and layout are important because they may affect the amount of time it will take the residents to answer the door.33
TIME OF DAY: A delay late at night might be expected if it reasonably appeared that the occupants had been asleep; e.g., the lights were out. Conversely, a delay might be more suspicious in the daytime or early evening.34
NO REASON FOR DELAY: Even a short delay may constitute a refusal if officers reasonably believed an occupant had heard their announcement but did not respond.35 As the court observed in People v. Elder, “Silence for 20 seconds where it is known that someone is within the residence suggests that no one intends to answer the door.”36 In contrast, in People v. Gonzales the court ruled that a delay of five seconds was insufficient because the officers knew that the resident was a woman who was home alone with two children, and they also knew the woman could not see them from the door.37
TRICKS AND RUSES: Officers need not comply with the knock-notice requirements if an occupant consented to their entry—even if the officers lied about who they were or their purpose. As the Court of Appeal explained, “Officers who reasonably employ a ruse to obtain consent to enter a dwelling do not violate [the knock-notice requirement], even if they fail to announce their identity and purpose before entering.”38 Some examples:
• Wearing a U.S. Post Office uniform, an officer obtained consent to enter for the purpose of delivering a letter.39
• An officer was admitted after he said, “It’s Jim, and I want to talk to Gail.” (Gail was an occupant and suspect.)40
• The suspect’s wife admitted an officer who claimed to be a carpet salesman sent by the welfare office to re-carpet the house.41
• A drug dealer told an officer to come in after the officer claimed that “Pete” had sent him to buy drugs.42
Flashbangs
If there is a high threat of violent resistance or destruction of evidence, and if officers comply with certain requirements, they may employ “flashbangs” before entering the premises. A flashbang is an explosive device that is tossed inside and which, upon ignition, emits a brilliant burst of light and a thunderous sound. This usually has the effect of temporarily disorienting and confusing the occupants, thereby giving officers a better chance of making a quick and safe entry.
Although officers are not required to obtain authorization from the judge to utilize flashbangs, the California Supreme Court has ruled their use may render an entry unreasonable unless the following circumstances existed:
1. REDUCED EXPLOSIVE POWER: The explosive power of the flashbang must have been limited to minimize the risk of injury to the occupants.
2. ADMINISTRATIVE APPROVAL: Before the warrant was executed, a police administrative panel must have determined that the use of flashbangs was the safest means of making a forced entry under the circumstances.
3. LOOK INSIDE: To help ensure that the flashbang did not land on or near a person or on flammable material, officers must have looked inside the targeted room before deploying the device.43
In addition to the above, officers should consider whether there are children in the home who might be traumatized by such a violent entry.44
Motorized battering rams
Breaking down a door by means of a motorized battering ram (essentially a small, armored vehicle fitted with a steel protrusion) presents a high risk of danger to the occupants and may even cause a partial building collapse. For this reason, the California Supreme Court indicated that a motorized battering ram may be used only if the following circumstances existed: (1) a police administrative panel and the judge who issued the warrant expressly authorized its use based on facts that established probable cause to believe that its deployment was reasonably necessary; and (2), before utilizing the vehicle, officers saw nothing to indicate that such a violent entry was unnecessary.45
Note that in determining whether there was probable cause, and whether the use of the vehicle was reasonably necessary, judges and officers must consider “the reliability of the ram under the specific circumstances as a rapid and safe means of entry, the seriousness of the underlying criminal offense and society’s consequent interest in obtaining a conviction, the strength of law enforcement suspicions that evidence of the crime will be destroyed, the importance of the evidence sought” and the possibility that the evidence could be recovered by less dangerous means.46
Securing the Premises
The first step after entering the home is to take complete control of the premises.47 As the United States Supreme Court observed, “The risk of harm to both the police and the occupants is minimized if the officers routinely exercise unquestioned command of the situation.”48 The Court also noted that, by assuming command, officers may reduce the risk that the occupants “will become disruptive” or otherwise “frustrate the search.”49
Detentions
In most cases, the most effective means of securing the premises is to detain everyone on the premises. But, as we discuss, the length and intrusiveness of a detention will vary, as some people may be detained until the search is completed, while others may be held only briefly to determine whether a full detention is warranted or whether they must be released.
DETENTION BASED ON REASONABLE SUSPICION: Officers may detain any person pending completion of the search—regardless of whether the person was inside or outside the residence—if they reasonably believed he was involved in the crime under investigation or constituted a threat to them.50 For example, in U.S. v. Bullock the court ruled that the detention of the defendant pending completion of the search was permitted because the “officers had articulable basis for suspecting that Bullock was engaged in drug activity from that residence.”51
DETENTION BASED ON RESIDENCY OR OCCUPANCY:
Even if officers lacked reasonable suspicion, they may, pending completion of the search, detain everyone who was inside the home when they arrived.52 As the Court of Appeal explained, “[A] search warrant carries with it limited authority to detain occupants of a residence while a proper search is conducted.”53 As with any type of detention, however, the detention of an occupant must be reasonable in its length and intrusiveness.54 For example, in Muehler v. Mena the Supreme Court ruled that the handcuffing of an occupant pending completion of the search was reasonable because the warrant authorized a search for weapons in the home of a gang member. Such a situation, said the Court, was “inherently dangerous” and the use of the handcuffs “minimizes the risk of harm to both officers and occupants.”55 On the other hand, the Ninth Circuit noted that “[a] detention conducted in connection with a search may be unreasonable if it is unnecessarily painful, degrading, or prolonged, or if it involves an undue invasion of privacy.”56
Note that if officers are searching a business that is open to the public, they may detain an occupant only if there was reasonable suspicion to believe that person was criminally involved.57 In other words, a person cannot be detained merely because he was present in a place where evidence is located if that place was open to the public.
ARRIVING UNDER SUSPICIOUS CIRCUMSTANCES: Officers may also detain a person pending completion of the search if (1) he arrived on the premises while the search was underway, and (2) he said or did something that reasonably indicated he was more than a casual visitor; e.g., the person entered the house without knocking, or he inserted a key into the lock, or he fled when he saw uniformed officers.58
BRIEF DETENTIONS TO DETERMINE STATUS: Under certain circumstances, officers may briefly detain people near the home for the limited purpose of determining whether there are grounds to detain them pending completion of the search, or whether they must be released.
DETAINING PEOPLE WITHIN THE CURTILAGE: Officers may ordinarily detain people who were in the front, back, or side yards.59
DETAINING PEOPLE WHO ARRIVE: A person may be detained if he arrived at the residence during the execution of the warrant, even though he did nothing to indicate he was a detainable resident or occupant.60
DETAINING PEOPLE WHO DEPART: A person who left the premises just before officers arrived may be detained if he was in the “immediate vicinity” of the premises when the detention occurred.61 However, if officers reasonably believed that the person had become aware of their presence as he left the premises, a brief detention a short distance away should be upheld to prevent him from alerting the occupants of the impending search.62
Other security precautions
In addition to detaining occupants and others, officers may take the following precautions if reasonably necessary.
SEIZING WEAPONS IN PLAIN VIEW: While inside the premises, officers may temporarily seize any weapon in plain view, even if the weapon was not contraband or seizable under the warrant.63
PAT SEARCHES: Officers may pat search any person inside or outside the premises if they reasonably believed the person was armed or dangerous.64 In addition, officers who are executing a warrant to search for illegal drugs or weapons may pat search (1) all occupants of the premises,65 and (2) anyone who arrived while the search was underway if the person entered in a manner that reasonably indicated he lived there or was otherwise closely associated with the residence; e.g., the person entered without knocking.66
OFFICER-SAFETY QUESTIONING: Even if an occupant had been arrested or was otherwise “in custody” for Miranda purposes, officers do not need a waiver to ask questions that are reasonably necessary to locate and secure deadly weapons on the premises, or to determine if there was someone on the premises who presented a threat to the officers.67 Such a situation would exist, for example, if the officers were searching for evidence of drug trafficking. As the Court of Appeal aptly put it:
Particularly where large quantities of illegal drugs are involved, an officer can be certain of the risk that individuals in possession of those drugs, which can be worth hundreds of thousands and even millions of dollars, may choose to defend their livelihood with their lives.68
SHOOTING DOGS: Shooting a dog on the premises is permitted only if officers can articulate a reasonable basis for such an extreme action.69 Furthermore, a court might find that such an action was unreasonable if officers knew there was a dangerous dog on the premises before they executed the warrant and failed to explore other options.70
Displaying the Warrant
After securing the premises, officers will ordinarily show the occupants a copy of the warrant. This is not, however, required under California law.71 In fact, as noted earlier, officers at the scene are not even required to possess a copy of the warrant. Still, displaying a copy is considered a “highly desirable” practice as it demonstrates to the occupant that “there is color of authority for the search, and that he is not entitled to oppose it by force.”72
As for warrants issued by federal judges, the United States Supreme Court ruled that, although officers must leave a copy of the warrant and a receipt at the scene, they are not required to serve an occupant with a copy at the outset of the search.73
What May Be Searched
A warrant must, of course, identify the home that officers may search. But warrants seldom specify every area and thing inside or on the grounds that may be searched. As the First Circuit observed, “The warrant process is primarily concerned with identifying what may be searched or seized—not how.”74 Thus, in U.S. v. Aljabari the court pointed out that the following:
The execution of a warrant will often require some interpretation of the warrant’s terms. A warrant that seems unambiguous to a magistrate in the confines of the courthouse may not be so clear during the execution of the search, as officers encounter new information not available when they applied for the warrant.75
As a result, the officers who are executing a warrant will often be required to exercise judgment in determining what places and things they may search. It is therefore the responsibility of the lead investigators to make sure—usually by means of a pre-search briefing—that all members of the search team understand the terms of the warrant, the parameters of the search, and any special restrictions.76 As the Ninth Circuit pointed out, “Typically, of course, only one or a few officers plan and lead a search, but more— perhaps many more—help execute it. The officers who lead the team that executes a warrant are responsible for ensuring that [the others] have lawful authority for their actions.”77 Along these same lines, the D.C. Circuit noted that search warrants “are not self-executing; they require agents to carry them out. In order for a warrant’s limitations to be effective, those conducting the search must have read or been adequately apprised of its terms.”78
As we will discuss in more detail as we go along, a basic requirement is that officers confine their search to places and things in which one or more of the listed items of evidence could reasonably be found.79 Thus, the United States Supreme Court explained that if a warrant authorizes a search for illegal weapons, it “provides authority to open closets, chests, drawers, and containers in which the weapon might be found.”80 More colorfully, the Seventh Circuit observed that if officers are looking for a “canary’s corpse,” they may search “a cupboard, but not a locket”; and if they are looking for an “adolescent hippopotamus,” they may search “the living room or garage but not the microwave oven.”81
Officers are not, however, required to confine their search to places and things in which the evidence is usually or commonly found. Instead, a search of a certain place or thing will be invalidated only if there was no reasonable possibility that the evidence would have been found inside.82
Before we begin, two other things should be noted. First, the descriptions of the places and things that may be searched “should be considered in a common sense manner,” which means that the courts should not engage in “hypertechnical readings” of the warrant.83 Second, all evidence obtained during the search will be suppressed if a court finds that the officers flagrantly disregarded the express or implied terms of the warrant as they conducted the search; i.e., if the officers conducted a “general search.”84 In the absence of flagrant disregard, a court will suppress only the evidence that was found in a place or thing that was not searchable under the warrant.85
Searching rooms and other interior spaces
If a warrant authorizes a search of a “single living unit”86—such as a single-family home, condominium, apartment, or motel room—it impliedly authorizes a search of the following:
COMMON AREAS: Unless the warrant says otherwise, officers may search all common areas, such as the living room, kitchen, bathrooms, hallways, recreation rooms, storage areas, basement, attic, and the yards.87
BEDROOMS: Officers may search all bedrooms, even bedrooms that are occupied by people who are not suspects in the crime under investigation.88 As the Ninth Circuit observed, “A search warrant for the entire premises of a single family residence is valid, notwithstanding the fact that it was issued based on information regarding the alleged illegal activities of one of several occupants of the residence.”89
For example, in U.S. v. Kyles 90 FBI agents obtained a warrant to search the apartment of Basil Kyles who was suspected of having robbed a bank the previous day. Basil’s mother answered the door and, when asked about a locked bedroom, said it belonged to her other son, Geoffrey; and that Geoffrey had the only key. The agents forced open the door and found evidence that incriminated both brothers. On appeal, Geoffrey argued that the search of his bedroom was beyond the scope of the warrant because he was not a suspect in the robbery when the warrant was executed and his room constituted a “separate residence.” The court disagreed, saying, “The FBI agents had no reason to believe that Geoffrey’s room was a separate residence: it had neither its own access from the outside, its own doorbell, nor its own mailbox. Mrs. Klyes’s statement that Geoffrey was the only person with a key to the room did not, by itself, elevate the bedroom to the status of a separate residential unit.”
COMPARE MULTI-RESIDENTIAL STRUCTURES: In contrast to single living units are buildings that have been divided into two or more living units, each under the exclusive control of different occupants. The most common buildings that fall into this category are apartment buildings, condominium complexes, duplexes, motels, and hotels. Authorization to search all residences or units in a multi-residential structure will not be implied. Thus, officers who are executing a warrant to search such a building may search only the residences or units that are listed in the warrant; e.g., a certain apartment.91
Although it does not happen often, officers will sometimes enter a home to execute a warrant and discover that it is actually a multi-residential structure because it had been divided into separate apartments. This occurred in Mena v. City of Simi Valley 92 where officers obtained a warrant to search a house for a firearm that one of the residents, Romero, had used in a gang-related drive-by shooting. The officers knew that the residence was a single-family residence occupied by a large number of people, mostly unrelated. But when they entered, they saw that many of the rooms adjacent to the living room were locked, some with padlocks on the outside of the doors. Furthermore, when they started to force open some of the doors, they saw that the rooms “were set up as studio apartment type units, with their own refrigerators, cooking supplies, food, televisions, and stereos.”
The owner of the house sued the officers, claiming the search was overbroad. The officers sought qualified immunity from the Ninth Circuit, but the court refused to grant it, saying, “the officers should have realized that the Menas’ house was a multi-unit residential dwelling” and, thus, “the officers’ search beyond Romero’s room and the common areas was unreasonable.”
Searching attached and detached structures Although it is preferable that warrants identify all searchable buildings on the property,93 officers may search attached and unattached structures that are ancillary to the residence or otherwise appear to be controlled by the occupants, such as garages and sheds (attached or detached).94 As the Ninth Circuit explained, “The curtilage is simply an extension of the resident’s living area, and we have previously held that such extensions become part of the residence for purposes of a search warrant.”95
The courts have also ruled that authorization to search outbuildings on the property will be implied if the warrant authorized a search of “premises” or “property” at a particular address.96 For example, in People v. Grossman the court ruled that a warrant to search “the premises located and described as 13328 Merkel Ave., Apt. A” impliedly authorized a search of a cabinet in the carport marked “A”.97
On the other hand, express authorization to search an outbuilding will be required if it reasonably appeared to be a rental property under the control of a third party.98
Also note that officers may search receptacles on the property (such as a mailbox or garbage can) if it reasonably appeared to be controlled by one or more of the occupants.99
Searching personal property
The term “personal property” essentially means items that people ordinarily carry with them, such as purses, backpacks, briefcases, luggage, satchels, and bags. Because it is usually impractical or impossible to include in a warrant a list of all searchable personal property on the premises, there is a general presumption that all such things belong to a resident and may therefore be searched.100 As the Court of Appeal explained, “The police may ordinarily assume that all personal property which they find while executing a search warrant is the property of a resident of the premises subject to a search.”101
This presumption does not apply, however, if the officers had reason to believe that the property belonged to a visitor. In that situation, they may search it only if one of the following circumstances existed: (1) there was reason to believe the visitor was an accomplice in the crime under investigation (e.g., a visitor’s purse was on a chair in a bedroom where a large quantity of methamphetamine had been found);102 (2) the item belonged to a person who was more than a casual visitor;103 or (3) there was reason to believe that “someone within the premises has had an opportunity to conceal contraband within the [item] immediately prior to the execution of the search warrant.”104
Searches for documents
If a warrant authorized a search for documents, officers may search any container on the premises in which such a document might reasonably be found.105 Thus, a warrant that authorizes a search for one or more documents necessarily authorizes a broad search. As noted in People v. Gallegos, “Documents may be stored in many areas of a home, car, motor home or garage. It is not unusual for documents to be stored in drawers or closets, on shelves, in containers, or even in duffle bags.”106
READING DOCUMENTS ON-SITE: If officers are authorized to search for documents, they may read any document they find to the extent necessary to determine if it is seizable.107
LABELS DONT MATTER: Officers may search containers of documents (such as envelopes, CDs, files, and binders) even though the container displays a label indicating that it does not contain seizable documents.108 As the Second Circuit observed, “[F]ew people keep documents of their criminal transactions in a folder marked ‘drug records.’”109
SEEK OPINION OF LEAD INVESTIGATOR: Officers who are not sure whether a document is covered under the warrant, or whether an entire file, box, or other container of documents may be read or removed, should refer the matter to the lead investigator or other designated officer.110
REMOVING DOCUMENTS FOR OFF-SITE SEARCH: If officers know ahead of time that it will be necessary to read many documents to determine whether they are seizable under the warrant, they will ordinarily seek express authorization to remove the documents and read them elsewhere.111 This is not only more convenient for the officers, it will reduce the intrusiveness of the search because they will be able to vacate the premises sooner.
In the absence of express authorization, officers may be impliedly authorized to remove documents if they discovered so many documents on the premises that it was not feasible to read them there.112 Thus, when this issue arose in U.S. v. Alexander, the court responded, “[I]t would have been difficult, and possibly more intrusive to Alexander’s privacy, for law enforcement to conduct an on-site review of each of more than 600 photographs to determine whether they were evidence of illegal conduct.”113 Another option in such a case is to seize the documents and seek a warrant that expressly authorizes a search of them off site.
When officers are removing documents for an offsite search, they may ordinarily take the entire file, folder, or binder in which the documents were stored. This not only serves to facilitate the search, it will help keep the files intact.114 But massive seizures of documents for the sole purpose of establishing dominion and control (searches for indicia) would ordinarily be deemed excessive.115
TIME LIMITATIONS: Although search warrants become void 10 days after issuance, the clock stops when the warrant was executed. Thus, is doesn’t matter that the off-site search took longer than 10 days to complete, so long as the officers were diligent. See “When Warrants May Be Executed,” above.
Searching computers, cellphones . . .
By definition, any device with digital storage capability contains information. Consequently, if a warrant authorizes a search for information (such as financial documents, photos, indicia) officers may want to search for it in such devices. Apart from the various technical issues (and there are lots of them), there are some legal issues that officers must address. The following are fairly common.
IS EXPRESS AUTHORIZATION REQUIRED? To date, most courts have ruled that a warrant which includes authorization to search for information impliedly authorizes a search for the information in any digital storage devices on the premises.116 For example, in People v. Balint the court ruled that it could “perceive no reasonable basis to distinguish between records stored electronically on the laptop and documents placed in a filing cabinet or information stored in a microcassette.”117 But because not all courts agree with this analysis, 118 and also because there is no downside, officers who are writing search warrants should almost always seek express authorization.
SEARCHING OFF SITE: Unless officers intend to conduct only a cursory search for information, they will usually seek express authority to seize digital storage devices on the premises and conduct the search at a location where they will have the time and tools for a thorough examination, such as a police station or forensic lab. As the First Circuit observed in a computer search case, “[I]t is no easy task to search a well-laden hard drive.”119
If the warrant does not expressly authorize an offsite search but, upon executing the warrant, it become apparent that one will be necessary, there is authority for seizing the device without express authorization and searching it later.120 But the better practice is to seize the equipment, then seek a warrant to search it off-site.
Two other things: First, if officers seized the device within 10 days after the warrant was issued, they do not need express authorization to begin or continue the search after the warrant expired. Officers should, however, seek court authorization if the seizure will be prolonged, especially if a legitimate business would be adversely affected by the loss of the device.121 Second, if officers determine that a certain device or file was not covered under the warrant or was not otherwise seizable, they should return it promptly.122 This is especially important if it was needed for a legitimate business.123
Searching people on the premises
While evidence can often be found hidden in or under the clothing of people, officers are not permitted to search the occupants for evidence unless the warrant expressly authorized it and also identified each searchable person by name, description, or both.124 As the First Circuit observed, “A search of clothing currently worn is plainly within the ambit of a personal search and outside the scope of a warrant to search the premises.”125 Or, as the U.S. Supreme Court put it, “[A] warrant to search a place cannot normally be construed to authorize a search of each individual in that place.”126
Two other things should be noted. First, a warrant that authorizes only a search of a particular person does not impliedly authorize officers to enter a home for the purpose of locating the person.127 Again, the warrant must contain express authorization for such an entry and search. Second, a warrant to search a person does not impliedly authorize a bodily intrusion of any sort.128
Searching vehicles on the premises
It is settled that officers do not need a warrant to search a vehicle if they have probable cause to believe it contains evidence of a crime.129 But this rule generally applies only if the vehicle was located on a street or other public place. So, because criminals may be just as likely to store evidence in their cars as in their homes, officers who write warrants will normally insert language that expressly authorizes a search of any vehicles on the property which are registered to the suspect or are used by him.
IMPLIED AUTHORIZATION TO SEARCH: If officers neglect to seek express authorization, there are three circumstances in which such authorization may be implied. First, officers may search an unlisted vehicle on the property if (a) the vehicle was parked within the curtilage of the house (e.g., in the driveway or garage); and (b) it was owned by, registered to, or controlled by, one of the residents.130
Second, an unlisted vehicle may be searched if the warrant authorized a search of the “premises” at the address (e.g., “the premises at 123 Main St.”) and the vehicle was in the driveway, a garage or other area within the curtilage of the residence. 131
Third, officers may search an unlisted vehicle if the warrant authorized a search of “storage areas” on the property, and the car was both inoperable and used solely for storage.132 It is also possible that officers may search an unlisted vehicle that belongs to a visitor if they had probable cause to believe the visitor was involved in the crime under investigation.133
ENTERING PRIVATE PROPERTY: A warrant that authorizes a search of a certain vehicle—and nothing more—does not constitute authorization to enter private property for the purpose of locating the vehicle or searching it.134 Thus, if probable cause is limited to a certain vehicle on private property, officers should seek a warrant that authorizes both a search of the vehicle and an entry onto the property.
OFF-SITE FORENSIC SEARCH: If officers have a warrant to search a vehicle for trace evidence or other evidence that can be detected only by means of special equipment, they may be impliedly authorized to remove the vehicle to a location where such a search can be carried out. As the court said in People v. Superior Court (Nasmeh), “Discovery of blood on the automobile and other circumstances warranted transporting it for a later, more scientific examination.”135 Still, if officers anticipate an off-site forensic search, they should seek express authorization for it.
Intensity of the Search
Not only must officers confine their search to places and things they were expressly or impliedly authorized to search, the search itself must have been reasonable in its intensity. In other words, it must not have been unreasonably probing, destructive, or lengthy—the key word being “unreasonably.”
THOROUGHNESS: A search will not be deemed unreasonably intensive merely because it was thorough. In fact, one court pointed out that a search must necessarily be thorough, otherwise it is “of little value.” 136 Similarly, the court in U.S. v. Snow noted that the word “search” has “a common meaning to the average person” which includes “to go over or look through for the purpose of finding something; explore, rummage; examine, to examine closely and carefully; test and try; probe, to find out or uncover by investigation.”137
LENGTH OF THE SEARCH: A search will not be deemed unduly intensive merely because it took a long time. Instead, what matters is whether the officers were diligent and whether there were circumstances that necessitated a prolonged search.138 For example, in People v. Gallegos the court noted the following in rejecting an argument that a search took too long:
[W]hile the search lasted approximately seven hours, this was not necessarily unreasonable given that officers searched the residence, truck, garage, and motor home. It goes without saying that the review of even a box of documents can take substantial time. . . . Moreover, the garage was cluttered, making a search more time consuming.139
DESTRUCTIVENESS: Because evidence is usually hidden, officers will sometimes need to damage property to find it. This is permitted so long as the intrusion was not “[e]xcessive or unnecessary.”140 As the Ninth Circuit observed:
[O]fficers executing a search warrant occasionally must damage property in order to perform their duty. Therefore, the destruction of property during a search does not necessarily violate the Fourth Amendment. Rather, only unnecessary destructive behavior, beyond that necessary to execute a warrant effectively violates the Fourth Amendment.141
For example, in U.S. v. Becker 142 the court ruled it was reasonable for officers to use a jackhammer to break up a slab of concrete in the suspect’s backyard because the officers had “ample reason” to believe that methamphetamine was buried under it. As the court pointed out, the officers knew that the slab was poured shortly after an accomplice’s home across the street had been searched, and that the slab was located next to a shop in the backyard in which officers had found evidence of methamphetamine production.
Note that officers may videotape the search to help protect themselves against false claims that they unnecessarily damaged or destroyed property.143
Seizing Evidence in Plain View
Officers may, of course, seize any items listed in the warrant and any items that were the “functional equivalent” of a listed item.144 In addition, under the “plain view” rule, they may seize an item that was not listed if both of the following circumstances existed:
1. the item was discovered while they were conducting a lawful search for listed evidence, and
2. they had probable cause to believe the item was evidence in the crime under investigation or some other crime.
Lawful search: Scope of search
The “lawful search” requirement is satisfied if officers discovered the unlisted evidence while they were searching places or things in which any of the listed evidence could reasonably have been found.145 It is “essential,” said the U.S. Supreme Court, “that the officer did not violate the Fourth Amendment in arriving at the place from which the evidence could be plainly viewed.”146 This subject was covered above in the sections “What May Be Searched” and “Intensity of the Search.”
Lawful search: Pretext searches
The question arises: Is a search “lawful” if it was conducted by an officer who was mainly interested in discovering unlisted evidence pertaining to some other crime? The answer is yes if both of the following circumstances existed: (1) the officer had been informed of the terms of the warrant, and (2) he restricted his search to places and things in which the listed evidence might reasonably be found. As the United States Supreme Court explained:
The fact that an officer is interested in an item of evidence and fully expects to find it in the course of a search should not invalidate its seizure if the search is confined in area and duration by the terms of the warrant.147
Thus, regardless of the officer’s motivation, if he observed evidence of another crime, he may seize it if he had probable cause to believe it was, in fact, evidence.
For example, in People v. Carrington 148 the defendant, Celeste Carrington, embarked on a one-woman crime spree along the San Francisco Peninsula, burglarizing businesses in which she had previously worked as a janitor. Because the crimes occurred in several cities, officers from these cities formed a task force and eventually developed probable cause to search Carrington’s home for property that was taken in a burglary that occurred in Los Altos. Among the officers who took part in the search were two investigators from the Palo Alto Police Department who were primarily interested in finding evidence that linked Carrington to a murder in their city in which an employee of a company was shot and killed during the commercial burglary. In the course of their search, the Palo Alto investigators saw a pager that belonged to the murder victim and also a key to his workplace. So they froze the scene and obtained a second warrant that authorized the seizure of the pager and key, plus a search for additional evidence pertaining to the murder. During the search, they found the murder weapon.
On appeal, Carrington argued that the evidence should have been suppressed because it was apparent that the Palo Alto officers were using the warrant as a pretext to look for evidence in their murder case. The California Supreme Court ruled, however, that the legality of the search did not depend on the secret motivation of the officers, but on whether they had restricted their search to places and things in which some of the listed evidence could have been found. And, said the court, they had:
In the present case, the police did not exceed the scope of the search authorized by the warrant, and they observed [the murder evidence] in plain view in defendant’s home. These observations were lawful because the presence of the officers at the location where the observations were made was lawful, regardless of the officers’ motivations.
Similarly, in People v. Williams 149 narcotics officers in Kern County obtained a warrant to search Williams’ house for drugs. Before leaving, they called the burglary-theft detail and requested “two bodies” to assist with the search. It turned out that the “two bodies” who were assigned the job belonged to two detectives who had previously received a tip that Williams was dealing in stolen property. The tip paid off because, while searching for drugs, the detectives seized a “plethora of electronic equipment, silverware, clocks, and firearms.” As a result, Williams was charged with possession of stolen property. On appeal, the court ruled the stolen property was discovered during a lawful search because “the officers did not move articles to get serial numbers or other indicia of ownership to any greater degree than one might expect in looking for hidden drugs pursuant to the warrant.”
In contrast, in People v. Albritton 150 an auto theft investigator accompanied narcotics officers when they executed a warrant to search Albritton’s home for drugs. The investigator knew that Albritton was a car thief, and when the search began he split off from the narcotics officers and went into Albritton’s garage and backyard where he found 18 vehicles. He then searched for their VIN numbers and learned that eight of the cars were stolen. Albritton was subsequently convicted of possessing stolen vehicles, but the court ruled the evidence should have been suppressed because, by examining the VIN numbers, the officer was conducting “a general exploratory search for unlisted property.”
Probable cause
As noted, officers may seize unlisted evidence under the plain view rule only if they had probable cause to believe it was, in fact, evidence of a crime.151 In discussing the nature of such probable cause, the U.S. Supreme Court said that it exists if “the facts available to the officer would warrant a man of reasonable caution in the belief that certain items may be contraband or stolen property or useful as evidence of a crime; it does not demand any showing that such a belief be correct or more likely true than false. A practical, nontechnical probability that incriminating evidence is involved is all that is required.”152
As we will now discuss, probable cause may be based on the knowledge of the officer who discovered the evidence, or the knowledge of civilians who have some special knowledge or expertise.
PROBABLE CAUSE ESTABLISHED BY OFFICERS: In most cases, probable cause to seize unlisted evidence will be based on the knowledge of the lead investigator or other officer who is familiar with the details of the crime. The following are some examples:
MURDER WARRANT: An investigator seized unlisted wire clippers because he knew that bailing wire had been used to bind the victims.153
MURDER WARRANT: An investigator seized unlisted “cut-off panty hose” because he knew that the murderers had worn masks and that cut-off panty hose are commonly used to make masks.154
BURGLARY WARRANT: An investigator seized unlisted bolt clippers because he knew that the burglars had used bolt cutters to gain entry.155
SOLICITATION OF MURDER WARRANT: While searching the home of a man who had solicited the murder of his estranged wife, an investigator seized an unlisted hand-drawn diagram of the wife’s home.156
MURDER WARRANT: An investigator seized unlisted shoes with waffled soles because he knew that “waffled-like shoe prints” had been found at the crime scene.157
NARCOTICS WARRANT: An investigator seized unlisted guns because “they were in close proximity to a plethora of drugs and drug-related equipment.”158
Note that, while all of the seized evidence in the above examples was relevant to the crime for which the warrant had been issued, officers may seize evidence pertaining to any crime if it was in plain view.159
PROBABLE CAUSE ESTABLISHED BY OWNER OF STOLEN
PROPERTY: In many burglaries and other theft-related crimes, the victim will be unable to provide a complete description of everything that was taken. So if officers obtain a warrant to search the suspect’s home for the stolen property, they may arrange to have the victim accompany them and notify them if he sees any property that was not listed in the warrant; and if he does, they may seize it.
For example, in People v. Superior Court (Meyers) 160 deputies in Marinwood developed probable cause to believe that Meyers had burglarized the home of his neighbors, Mr. and Mrs. Lane. The Lanes reported that “well over a hundred” items were stolen and they “could not recall everything that was taken.” While executing a warrant to search Meyers’ home, deputies asked the Lanes to watch and notify them if they saw any of their property. During the search, the Lanes identified several dozen unlisted items which the deputies seized. In ruling that this procedure was lawful, the California Supreme Court said:
To require the victims of a massive burglary to recall every missing facecloth and coffee pot is to require the impossible. The procedure which the police pursued in the present case reasonably accommodated the legitimate interests of effective law enforcement without seriously impinging upon defendant’s right to be secure in his house and effects against indiscriminate governmental intrusion.
There are, however, two limitations on victimassisted searches. First, the victims may not search— they may only watch and notify officers if they see any of their property. Second, if the victim identifies an item, officers may not seize it until the victim has explained how he was able to identify it. Although the victim need not provide a lengthy or elaborate explanation, something more than “That’s mine” is required. For example, in one case the victim’s statement “I recognize it because of the design” was deemed sufficient.161
PROBABLE CAUSE ESTABLISHED BY EXPERT: If a warrant authorizes a search for property that cannot be identified without assistance from an expert in some field, officers may arrange to have such a person accompany them when they execute the warrant.
Furthermore, unlike victim-assisted searches, the expert may, if necessary, actually conduct the search. For example, in People v. Superior Court (Moore) 162 officers in Santa Clara County were investigating a theft of trade secrets from Intel. During the course of the investigation, they obtained a warrant to search the suspect’s business for several technical items, such as a “Magnetic data base tape containing Intel Mask data or facsimile for product No. 2147 4K static Ram.”
The affiant knew that he would need an expert to identify most of these items, so he obtained authorization to have Intel technicians assist in the search. Actually, the technicians did the searching while the officers watched. As the court pointed out:
[N]one of the officers present did any searching, since none of them knew what items described in the warrant looked like. Rather, at the direction of the officer in charge, they stood and watched while the experts searched.
In addition to finding some of the listed evidence, the experts found several unlisted items that they set aside. Afterward, officers obtained a second warrant that authorized the seizure of these items.
On appeal, Moore argued that the search by the Intel experts violated the rule (discussed above) that crime victims cannot actually conduct the search. But the court ruled that this restriction does not apply where, as here, the complexity of the search would have made it impossible or impractical to do so. Among other things, the court said,:
[T]here is no requirement that such experts, prior to stating their conclusions [that the property was stolen], engage in the futile task of attempting to educate accompanying police officers in the rudiments of computer science, or art forgery, or any other subject of scientific or artistic enterprise.
It should be noted that officers may also utilize a dog who had been trained to detect an item listed in the warrant, such as explosives or drugs. Although the United States Supreme Court recently placed restrictions on walking a drug-detecting dog onto a person’s front yard to sniff for narcotics,163 that ruling pertained only to warrantless intrusions.
PROBABLE CAUSE TO SEIZE INCOMING PHONE CALLS:
Under certain circumstances, officers who are executing a warrant may “seize” incoming phone calls under the plain view rule if they had probable cause to believe the caller would provide incriminating information. By “seizing” incoming phone calls, the courts mean answering the phone, posing as the suspect or an accomplice, and engaging the caller in a conversation about the crime under investigation. This is especially useful if the premises are being used for illegal activities such as drug trafficking, prostitution, and sales of illegal weapons.164
When to Seek a Second Warrant
Officers are not ordinarily required to obtain a second warrant to search a place or thing they could have lawfully searched under the terms of the first warrant. Thus, in People v. Rangel the Court of Appeal observed, “Federal cases have recognized that a second warrant to search a properly seized computer it not necessary where the evidence obtained in the search did not exceed the probable cause articulated in the original warrant.”165 As we will now discuss, however, there are three situations in which a second warrant may be required.
SEEKING EVIDENCE OF OTHER CRIMES: While conducting a search, officers will sometimes find evidence pertaining to a crime other than the one for which the warrant was issued. If, upon observing the evidence, the officers had probable cause to believe it was, in fact, evidence of a crime, they may seize it under the plain view rule (which we discussed earlier). But if the officers want to expand their search to look for more evidence of the new crime, they will need a second warrant that specifically authorizes it. For example, if officers are searching for evidence of drug trafficking, and if they open a container and find child pornography, that evidence will be admissible under the plain view rule. But they may not search for more evidence of child pornography unless they obtain a second warrant.166
WRONG DESCRIPTION: Upon arrival, officers may learn that the description in the warrant was incorrect. For example, the warrant might contain the wrong house number or the premises might consist of two separate residences instead of one. When this happens, the required procedure will depend on whether the error was discovered before officers made their presence known.
Specifically, if the officers had not alerted the occupants to the impending search, they will usually leave and seek a new warrant with a corrected description. Thus, when officers failed to do this in U.S. v. Garcia, the court said, “Obtaining a corrected warrant may have been the better choice, particularly since there was ample time to do so.”167 But if the error was discovered after the suspects became aware of the impending search, officers cannot simply leave the premises to seek a new warrant because the evidence will likely be gone when they return. Consequently, they will usually secure the premises while they promptly seek a corrected warrant.
Post-Search Procedure
After they have completed the search, officers must comply with the following post-search requirements:
“ONE WARRANT, ONE SEARCH RULE: A search warrant authorizes only a single search. This means that, once officers have departed the scene, they will need a new warrant to re-enter the premises to search for additional evidence.168
LEAVE RECEIPT: Officers must leave a receipt for the property they seized.169
“RETURN OF WARRANT AND INVENTORY: Within 10 days after the warrant was issued, the original signed warrant must be filed with (“returned” to) the judge along with a sworn inventory of all seized property. 170
Note that in calculating the 10-day period, do not count the day on which the warrant was issued.171
Also note that, if reasonably necessary, officers may file a partial inventory, so long as they file a complete inventory when they are able to do so.172
OFFICERS MUST RETAIN THE EVIDENCE: Although Penal Code sections 1523 and 1529 say that the officers must bring the evidence to the judge, Penal Code sections 1528(a) and 1536 say the officers must retain the evidence pending further order of the court. Because judges do not want officers to deliver loads of drugs, stolen property, murder weapons and other sordid things to their chambers, the Court of Appeal has ruled the evidence must be retained by the officers unless the warrant directs otherwise.173
DISPOSITION OF EVIDENCE SEIZED BY MISTAKE: Officers who mistakenly seized property that was not listed in the warrant may release it to its owner without court authorization.174
INSPECTION OF DOCUMENTS BY OUTSIDE AGENCY: If officers from another agency want copies of seized documents, they should seek an order to examine and copy the documents. This order should be supported by an affidavit establishing probable cause to believe the documents are evidence of a crime they are investigating. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.3%3A_Executing_Search_Warrants.txt |
Before the Sheriff may break the party’s house, he ought to signify the cause of his coming, and make request to open doors. Semayne’s Case (1604)1
The knock-notice rule has been irritating law enforcement officers for over 400 years. And their complaint is well-founded: If officers have a legal right to enter a house to execute a search warrant or arrest someone, why must they engage in what is arguably a “meaningless formality?”2 And a dangerous one, too. As the Court of Appeal observed, “[T]he delay caused by [knocknotice] might give a forewarned occupant exactly the opportunity necessary to arm himself, causing injury to officers and bystanders.”3 Knock-notice is also notorious for giving suspects an opportunity to destroy evidence, especially drugs.
But there is another side to the argument; specifically, knock-notice may help prevent a violent response by the occupants. As the California Supreme Court pointed out, “[F]ew actions are as likely to evoke violent response from a householder as unannounced entry by a person whose identity and purpose are unknown to the householder.”4 Thus, the Court of Appeal noted that while “[o]ne particular officer may be willing to risk the chance of sudden violence,” the rule “is also directed toward the protection of his fellow officers.”5
So it appears that the people on both sides of the door have valid concerns and vital interests at stake. How can they be resolved? In the past, many courts ignored the problem and simply ruled that knock-notice was strictly required under the Fourth Amendment.6 In 1995, however, the Supreme Court rejected this idea, concluding that the Fourth Amendment requires only that officers enter in a “reasonable” manner, which may or may not require an announcement.7 Thus, in addition to knocknotice, the reasonableness of a forcible entry might also depend on the manner in which officers entered, the time of day or night they entered, whether they damaged the premises, and whether they saw or heard anything before entering that reasonably indicated that full compliance with the knocknotice rule would be counterproductive. Other circumstances include the seriousness of the crime under investigation, the nature and destructibility of the evidence being sought, how the occupants responded to searches and police encounters in the past, the size and layout of the premises, and the existence of any extraordinary security measures. We will discuss these circumstances later in this article, plus the controversial rule that officers may not enter unless they are refused entry. But first, it is necessary to explain what officers must do to comply with the knock-notice procedure.
Knock-Notice Procedure
If knock-notice is required, officers may comply fully or substantially with the procedure we will now discuss. Substantial compliance occurs when officers take action that achieves the objective of the rule but does not constitute full compliance.8
1. KNOCK: Although it is called the “knocknotice” rule, there is no requirement that officers actually knock on the door or ring the doorbell. Instead, they must take action that is reasonably likely to alert the occupants of their presence, which also provides some assurance that the occupants will hear the officers’ announcement.9 Substantial compliance also results when it is apparent that one or more of the occupants saw the officers arrive.10 As the Ninth Circuit observed, “[O]ne cannot ‘announce’ a presence that is already known.”11
2. ANNOUNCE AUTHORITY: Officers must also announce their authority by, for example, yelling “Police officers.”12 But this requirement may also be satisfied if at least one of the officers was in uniform and was visible to the occupants.13
3. ANNOUNCE PURPOSE: Officers are not required to engage in an explanation of their purpose. Instead, they are simply required to declare it; e.g., “search warrant,” “parole search,” “probation search,” “arrest warrant.”14 This requirement may also be excused altogether if the officers’ purpose was reasonably apparent.15 As the Court of Appeal explained in People v. Mayer, “[S]trict compliance with [the knock-notice statute] is excused where the entering officers reasonably believe the purpose of entry is already known to the occupants.”16 For example, it would seem to be reasonable to infer that the occupants were aware that the officers intended to conduct a search or make an arrest if, immediately after they announced their authority, they heard an occupant running, or if an occupant attempted to shut the door on them.17
4. WAIT FOR REFUSAL: In the absence of exigent circumstances, officers must do one more thing before entering: wait until they were admitted or until it reasonably appeared that the occupants did not intend to admit them.18 This is an especially controversial requirement because the occupants have no legal right to refuse entry. In addition, it is notoriously difficult for officers to determine the point at which a “refusal” had actually occurred. In any event, the courts have attempted to resolve these issues by ruling that a refusal can occur by either affirmative conduct or inaction.
Refusals by affirmative conduct
An immediate entry will ordinarily be permitted if it reasonably appeared that an occupant saw the officers and heard their announcement yet did not respond immediately or if he started to escape.19 The most common types of refusal by affirmative conduct are when officers hear sounds from inside the house that indicate the occupants are attempting to destroy evidence or flee. See “When Compliance Is Not Required” (Destruction of evidence, and Flight, below).
Refusals by inaction
The most common type of refusal is a refusal by inaction, which occurs when officers are not admitted into the premises within a reasonable time after they announced their authority and purpose.20 As the Ninth Circuit observed, “The refusal of admittance contemplated by the [knock-notice] statute will rarely be affirmative, but will oftentimes be present only by implication.”21 For example, in People v. Montenegro 22 the defendant looked out a window, saw the officers at the front door, then mouthed the words, “Okay, okay.” When he did not promptly open the door, the officers demanded entry. Still no response, so “within seconds” the officers broke in. The court ruled that Montenegro’s “failure to comply in these circumstances justified entry,” adding that “the amount of time [the officers waited] is irrelevant because Montenegro acknowledged their presence” but did nothing. On the other hand, a delay will not justify an expedited entry if officers were aware of circumstances that justified the delay; e.g., officers saw that the occupant was asleep on a sofa.23
What’s a “reasonable” time? As would be expected, there is no minimum wait time.24 Instead, it all depends on the totality of circumstances.25 Thus, the Supreme Court acknowledged that “[w]hen the knock-and-announce rule does apply, it is not easy to determine precisely what officers must do. How many seconds’ wait are too few?”26 In making this determination, the following circumstances are frequently noted.
SIZE AND LAYOUT: The larger the structure, the longer it might take the occupants to answer the door (and vice versa).27 As the Supreme Court explained, the required wait time “will vary with the size of the establishment, perhaps five seconds to open a motel room door, or several minutes to move through a townhouse.”28
TIME OF DAY: A delay late at night should be expected if it reasonably appeared the occupants had been asleep. Conversely, a delay might be more suspicious in the daytime or early evening.29
DESTRUCTIBLE EVIDENCE INSIDE: In determining whether a delay constituted an implied refusal, officers may consider the nature of the evidence they are authorized to search for and seize. For example, if a warrant authorizes a search for drugs, documents, or anything else that could be disposed of quickly, a short delay might be viewed with more concern than if officers were searching for, say, a stolen piano. Furthermore, in cases where officers are looking for destructible evidence, they need only wait for the amount of time they estimate it would take an occupant to dispose of the evidence; i.e., they do not need to wait for the amount of time it would take to reach the front door. As the Supreme Court explained in United States v. Banks, “[W]hat matters is the opportunity to get rid of cocaine, which a prudent dealer will keep near a commode or kitchen sink.”30
When Compliance is Not Required
There are several situations in which officers are not required to comply fully or even partially with the knock-notice procedure. This does not mean that officers should never attempt to comply under these circumstances. It just means that if these circumstances existed and officers concluded that, under the existing circumstances, they need to make an immediate entry, they may do so.
No-knock warrants
When executing a search or arrest warrant, officers may make a no-knock entry if it was authorized by the judge who issued the warrant. Consequently, if the affiant reasonably believed that a no-knock entry was necessary, he may request the judge to authorize it on the warrant if the affidavit contained facts constituting “reasonable suspicion”31 that (1) compliance would provide the occupants with time to arm themselves or otherwise engage in violent resistance, (2) compliance would provide the occupants with time to destroy evidence, or (3) compliance would serve no useful purpose; e.g., the premises were abandoned.32 But even if the judge grants no-knock authorization, officers must not make an unannounced entry if they become aware that circumstances had changed and, as the result, there was no need for an immediate entry.33 On the other hand, if the judge refuses to grant the officers’ request, they may nevertheless make a no-knock entry if, as the result of changed circumstances, they reasonably believed it was necessary. As the Supreme Court explained, “[A] magistrate’s decision not to authorize no-knock entry should not be interpreted to remove the officers’ authority to exercise independent judgment concerning the wisdom of a no-knock entry at the time the warrant is being executed.”34
Exigent circumstances
Officers may also dispense with the knock-notice procedure if, upon arrival, they became aware of facts that constituted “reasonable suspicion” that compliance would be dangerous or would result in the destruction of evidence. As the Supreme Court explained, there are “many situations in which it is not necessary to knock and announce,” such as “when circumstances present a threat of physical violence, or if there is reason to believe that evidence would likely be destroyed if advance notice were given, or if knocking and announcing would be futile.”35 Specifically, there are three types of exigent circumstances that will justify noncompliance: (1) imminent danger to officers or others, (2) imminent destruction of evidence, and (3) futility. DANGER: Compliance with the knock-notice requirements is excused if officers reasonably believed they or someone else would be harmed unless they made an immediate entry.36 In the words of the Supreme Court, “[I]f circumstances support a reasonable suspicion of exigency when the officers arrive at the door, they may go straight in.”37 The following are some examples:
• Entry to arrest an armed prison escapee who vowed he would “not do federal time.”38
• Entry to arrest a suspect in the murder of a police officer.39
• Search warrant for drugs; suspect had previously “expressed his willingness to use firearms against the police” and was known to have access to firearms.40
• Search warrant for drugs; suspect’s apartment was protected by a steel door; officers knew there was a loaded handgun and a “large amount” of crack cocaine inside the apartment.41
• Search warrant on meth lab; the house “was equipped with security cameras and flood lights. Windows were papered over, suggesting that the occupants of the home were concerned with protecting their illegal methamphetamine laboratory.”42
• There was probable cause that the house contained explosives; as the uniformed SWAT team was assembling outside, one of the occupants opened the door, saw them, and immediately closed the door.43
• Officers went to the suspect’s home to arrest him for rape; the rapist had been armed with a knife. As officers arrived, they saw a gun in a car parked nearby. When they got to the door they “heard what sounded like running footsteps.”44
DESTRUCTION OF EVIDENCE: If officers were executing a search warrant or were securing the premises pending issuance of a warrant, an expedited entry would be permitted if they reasonably believed there was destructible evidence on the premises that would be destroyed if they delayed making entry. This is especially likely to occur in drug cases.45 Nevertheless, officers must have been aware of circumstances indicating an imminent threat to the evidence; i.e. they cannot assume that all entries into drug houses will automatically warrant a no-knock entry.46
The following are some examples of no-knock entries in drug cases have been deemed reasonably necessary:
• When officers knocked, the defendant “cracked” open the door, saw a uniformed officer, then slammed the door shut.47
• When an officer announced his authority and purpose, two people inside a “heavily barricaded” drug house started running through the house.48
• Upon announcing, officers heard “very fast movements toward the rear of the apartment.”49
• The suspect was a felon operating under an alias, his apartment had been fortified by a steel door, there was a loaded handgun and a “large amount” of cocaine inside the apartment.50
• Officers knew that the defendant had “an extensive arrest record including arrests for possession and sale of heroin”; his house was a “virtual fortress”; when officers arrived and identified themselves, the defendant attempted to close a gate to prevent their entry.51
FLIGHT: Compliance with the knock-notice procedure would not be required if officers reasonably believed that the occupants had started to flee. Here are two examples:
• FBI agents had probable cause to believe a fugitive who was wanted for several violent offenses involving guns was inside a motel room; before they entered, a friend of the fugitive who was arrested outside the room yelled “Run!” 52
• Officers in hot pursuit of a burglary suspect chased him into a house.53
FUTILITY: Finally, compliance is not required if doing so would be futile or otherwise serve no useful purpose.54 For example, knocking and announcing would be excused if officers reasonably believed that no one was inside the premises.55 “Where no one is present,” said the Court of Appeal, “officers executing a search warrant . . . may make forcible entry without giving notice of their authority or purpose.”56
Tricks and ruses
Officers who have a warrant need not comply with the knock-notice procedure if an occupant consented to their entry—even if the officers lied about who they were or what they wanted. This is because the objective of giving notice of an imminent entry would have been achieved when the occupant consented to their entry. Thus, the Court of Appeal said, “Officers who reasonably employ a ruse to obtain consent to enter a dwelling do not violate [the knock-notice statutes], even if they fail to announce their [true] identity and purposes before entering.”57 The following are examples:
• An officer wearing a Post Office uniform went to the suspect’s house to execute a search warrant (the other officers hid outside). When one of the suspects answered the door, the officer said he had a special delivery letter for the other suspect and was told, “Sure, come on in.”58
• Officers went to the suspect’s house to conduct a probation search. An undercover officer knocked on the door and told the suspect’s roommate, “It’s Jim, and I want to talk to Gail” who was an occupant and suspect. When the officer saw Gail standing behind her roommate, he identified himself and entered.59
• The suspect’s wife admitted an undercover officer after he said he was a carpet salesman sent by the welfare office to recarpet the house.60
• A drug dealer admitted an undercover officer after the office told him that “Pete” had sent him to buy drugs.61
Suppression of Evidence
As noted earlier, the Supreme Court has ruled that a failure to comply with the knock-notice procedure does not constitute a violation of the Fourth Amendment. Consequently, a failure to comply will not result in the suppression of evidence if the officers’ entry was otherwise reasonable. Suppression is also inappropriate if officers had a legal right to enter, in which case the evidence would have been discovered inevitably. As the Supreme Court explained in a search warrant case, regardless whether or not the officers complied with the knock-notice requirements, “the police would have executed the warrant they had obtained, and would have discovered the gun and drugs inside the house.”62
This does not mean, however, that officers should not attempt to comply when feasible. Remember that one of the main objectives of the knock-notice rule is to reduce the chances of a violent confrontation when the occupants of a home do not know the identity and intentions of the people who are demanding admittance. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.4%3A_Knock-Notice.txt |
Protective sweeps are a necessary fact of life in the violent society in which our law enforcement officers must perform the duties of their office.1
While homes are places in which people ordinarily feel safe, they can be dangerous places for officers who have entered to make an arrest. “[A]n in-home arrest,” said the Supreme Court, “puts the officer at the disadvantage of being on his adversary’s ‘turf.’ An ambush in a confined setting of unknown configuration is more to be feared than it is in open, more familiar surroundings.” 2 For this reason, the Court ruled that officers who have entered a residence may, under certain circumstances, conduct a type of search commonly known as a “protective sweep” or “walk through.”
It should be noted that protective sweeps are only one of five types of protective searches that officers may be permitted to conduct in the course of detaining or arresting suspects. The other four are:
• Pat searches: Outside-the-clothing searches to locate weapons in the possession of a suspect who is believed to be armed or dangerous.
• Protective vehicle searches: Searches of a detainee’s vehicle when officers have reason to believe there is a weapon inside.
• Chimel searches: Searches of a residence incident to the arrest of an occupant. (This subject is covered in the article on searches incident to arrest beginning on page one.)
• Vicinity sweeps: A search of areas in a home that are “immediately adjoining” the place in which an arrest occurred. (This subject is also covered in the article on searches incident to arrest.)
There is one other type of sweep that should be noted. Officers who have lawfully entered a home to arrest an occupant may, if necessary, search the premises for the arrestee.3 While these searches are not “protective” in nature (because their objective is apprehension, not protection), they constitute “sweeps” because they are limited to a cursory inspection of places in which the arrestee might be hiding. Consequently, they must be conducted in accordance with the scope and intensity rules applicable to protective sweeps.
One other thing: The United States Supreme Court’s decision in Arizona v. Gant, which we discussed in the previous article, will not result in additional limitations on protective sweeps. That is because the restrictions on protective searches imposed by Gant were intended to limit them to situations in which there existed a demonstrable threat. But, as we will discuss in this article, protective sweeps are already subject to this restriction.4
Requirements
The following are the requirements for conducting a protective sweep of a residence, business, or other structure:
1. Lawful entry: Officers must have had a legal right to enter; e.g., arrest warrant, consent, hot or fresh pursuit.
2. Person on premises: Officers must have had reason to believe there was a person on the premises (other than the arrestee) who was hiding or had otherwise not made himself known.
3. Danger: Officers must have had reason to believe that that person posed a threat to them.
Proof requirements
Because suppression motions pertaining to sweeps are often lost because officers or prosecutors failed to satisfy the various proof requirements, we will begin by discussing this subject.
LEVEL OF PROOF: The United States Supreme Court has ruled that officers who have lawfully entered a residence to make an arrest must have reasonable suspicion to believe that a dangerous person is on the premises.5 “In order to justify the protective sweep,” said the Sixth Circuit, “the government bore the burden of providing sufficient facts to support a reasonable belief that a third party was present who posed a danger to those on the arrest scene.” 6
SPECIFIC FACTS: While reasonable suspicion is a lower level of proof than probable cause, it can exist only if officers were able to articulate one or more circumstances that reasonably indicated there was, in fact, someone on the premises who posed a threat.7 Thus, in U.S. v. Moran Vargas the Second Circuit ruled that a sweep of a bathroom was unlawful because “the DEA agents’ testimony did not provide sufficient articulable facts that would warrant a reasonably prudent officer to believe that an individual posing a danger to the agents was hiding [there].”8 Similarly, a sweep will not be upheld merely because a threat was theoretically possible,9 although it may be based on an officer’s reasonable inferences from the surrounding circumstances.10
SWEEP BASED ON NO INFORMATION: A sweep cannot be justified on grounds that officers did not know whether a threat existed and, therefore, could not rule out the possibility.11 As the California Supreme Court pointed out, while “[t]here is always the possibility that some additional person may be found,” such a “mere possibility” is “not enough.”12 For example, in U.S. v. Ford the court ruled that a sweep was unlawful because its only justification was the following testimony from an officer: “I did not know if there was anybody back there. I wanted to make sure there was no one there to harm us.”13
“ROUTINE SWEEPS: Because articulable facts are required, a sweep will not be upheld on grounds that it was conducted as a matter of routine or departmental policy. For example, in U.S. v. Hauk the following occurred during cross-examination of a police detective in Kansas City, Kansas:
DEFENSE ATTORNEY: So I take it then it is just a matter of routine when you are executing arrest warrants at a particular residence, that a protective sweep then is done, because in your experience there is at least some likelihood that some other person might be present, correct?
DETECTIVE: Absolutely.
The court responded by pointing out that “[t]he Fourth Amendment does not sanction automatic searches of an arrestee’s home, nor does the factintensive question of reasonable suspicion accommodate a policy of automatic protective sweeps.”14
In another case in which an officer testified that sweeps are “standard procedure,” the Ninth Circuit reminded readers that “the fourth amendment was adopted for the very purpose of protecting us from ‘routine’ intrusions by governmental agents into the privacy of our homes.” The court added, “It is dismaying that any trained police officer in the United States would believe otherwise.”15
Lawful entry
Having covered the proof requirements imposed on officers and prosecutors, we will now examine the prerequisites for conducting protective sweeps, the first of which is that the officers must have had a legal right to enter the premises. Although this requirement is typically satisfied when the entry was based on a valid search or arrest warrant, as mentioned earlier it may also be based on an exception to the warrant requirement, such as hot pursuit.16
CONSENSUAL ENTRIES: Officers may conduct a sweep if the threat materialized after they had made a consensual entry. But problems may arise if they knew of the threat before they entered, and if they intended to conduct a sweep if consent was granted. In such a situation a court might rule that the consent was not “knowing and intelligent” if the officers did not inform the consenting person that his consent to enter would automatically result in a sweep.17
THREAT DEVELOPS WHILE OFFICERS WERE OUTSIDE:
While most protective sweeps occur when the threat developed after officers had entered, sweeps are also permitted if the officers were outside the premises and suddenly became aware that a person in the residence constituted an immediate threat to them.18 In such cases, however, the entry will be deemed lawful only if officers had probable cause to believe that such a threat existed.19
Person on premises
The second requirement is that officers must have had reasonable suspicion to believe there was someone on the premises who had not made himself known.20 In some cases, this requirement may be established through direct evidence, as when officers see someone inside;21 or when they hear a voice;22 or when an accomplice, neighbor, or other person says there is someone inside.23
This requirement may also be met by means of reasonable inference, which is typically based on one or more of the following circumstances:
WARNING TO OTHERS: A person who was contacted or detained suddenly shouted a warning apparently to unseen occupants of the premises.24
SOUNDS: Officers heard a sound that could have been made by a person; e.g., “scuffling noises from inside,”25 “footsteps.”26
MOVEMENT: Officers saw something move (e.g., a curtain or door) if the cause was not reasonably attributable to other factors, such as wind.27
CAR PARKED IN DRIVEWAY: Officers saw a car in the driveway, and they knew it belonged to someone who was unaccounted for; e.g., “[t]hree vehicles, not one, were parked in the driveway”;28 a “red Camaro pulled into [the suspect’s] driveway. The driver disappeared, perhaps into the house.”29
CAR PARKED NEARBY: A car parked nearby may also help create suspicion; e.g., officer saw “two cars parked sufficiently close to the residence to create a reasonable possibility that former occupants of the vehicles might be inside.”30
MULTIPLE OCCUPANTS: Officers had reason to believe that two or more people were in or about the premises when they arrived; and although some of these people had been contacted or detained, others were unaccounted for.31 In determining whether these circumstances justified a sweep, the courts have noted the following:
• “[N]umerous cars and individuals entered and exited, which meant that at any given time the officers might have lacked an accurate count of suspects present.”32
• Officers saw an “undetermined number of participants” in a pot partly in a residence.33
• Officers “did not know whether the five men who had come out of the garage included all five of the accused burglars.” 34
• Officers saw “ additional occupants in the darkened living room” and “a person other than [the suspect] exiting and reentering the apartment.”35
• Because five suspects entered and four exited, the officers had “very good reason” to believe that “at least one” suspect was hiding in the warehouse.36
MULTIPLE PERPETRATORS: The arrestee was wanted for a crime committed by two or more people, some of whom had not yet been apprehended. As the Third Circuit observed in Sharrar v. Felsing, “The reasonable possibility that an associate of the arrestees remains at large” is a “salient” concern “for which a warrantless protective sweep is justified.”37 For example, the following circumstances were deemed relevant:
• The officers “had yet to encounter Paopao’s suspected confederate.”38
• “Prior to the entry, the officers reasonably believed that at least six men were involved in distribution of cocaine.”39
• The officers knew that the occupants “served as enforcers for the drug trafficking operation.”40
• “[T]he officers knew that the day prior [to his arrest], Richards had been seen with Moore, a suspect in the murder investigation. When Richards met them at the door, the officers did not know whether Moore was inside.”41
• The suspect “habitually pursued his criminal activities with accomplices.” 42
SITE OF CRIMINAL ACTIVITY: It is relevant that the house was the center of operations for a criminal conspiracy or other ongoing criminal enterprise (such as buying or selling stolen property, organized crime, terrorism) and that officers conducting surveillance had previously seen people entering and exiting; e.g., “the residence was the site of ongoing narcotics activity,”43 “the house was sometimes used as a place for gang members to gather and conduct illegal activities,”44 “over the years, [the officer] had routinely observed individuals coming and going from the house,”45 other people were commonly present when the arrestees sold drugs to undercover officers in their homes.46
EVASIVE ARRESTEE: Finally, it is highly suspicious that officers had contacted or detained a person who, when asked if anyone else was on the premises, did not respond or was evasive.47 Although officers must take into account the arrestee’s assertion that no one else was on the premises, they are not required to believe him.48
A threat
In addition to having reasonable suspicion that an unaccounted for person was on the premises, officers must have had reason to believe that that person posed a threat to them. In the words of the Supreme Court, officers must be aware of “articulable facts” which “would warrant a reasonably prudent officer” in believing that the person posed “a danger to those on the arrest scene.”49
The existence of such a threat may be based on direct or circumstantial evidence. A common example of direct evidence is a tip from a reliable informant who had reason to believe the occupants were armed or that they would resist arrest.50
As for circumstantial evidence, it appears to be sufficient that (1) the officers had identified themselves in such a manner that anyone on the premises would have known who they were, and (2) they reasonably believed that one or more of the people on the premises were involved in crimes involving weapons or violence.51 Other circumstances that are often noted include the following:
• FIREARM ON PREMISES: Officers saw a firearm or ammunition inside the house.52
• EVASIVE Answer ABOUT WEAPONS: An occupant gave an evasive answer when asked if there were any weapons on the premises.53
• DANGEROUS ASSOCIATES: The arrestee associated with people who were known to be armed or dangerous; e.g., drug dealers, gang members.54
• REFUSAL TO ADMIT: The occupants refused to admit the officers.55
Sweep Procedure
Because the only lawful objective of a sweep is to locate and secure “unseen third parties who may be lurking on the premises,”56 officers must limit their search to a “quick” and “cursory” inspection of places in which a person might be hiding.57 Said the Fifth Circuit, “The protective sweep must cover no more than those spaces where police reasonably suspect a person posing danger could be found, and must last no longer than the police are otherwise constitutionally justified in remaining on the premises.”58
For example, while officers may look inside closets, behind large furniture, under beds, and under piles of clothing, they may not look under rugs, inside desk drawers or in small cabinets.59 Thus, in U.S. v. Ford 60 the court ruled that a sweep conducted by an FBI agent was excessive because he had lifted a mattress (finding cocaine) and had looked behind a window shade (finding a gun). In contrast, the court in U.S. v. Arch ruled the sweep was sufficiently limited because “[t]he evidence indicates that the officers did not dawdle in each room looking for clues, but proceeded quickly through the motel room and adjoining bathroom, leaving once they had determined that no one was present.”61
PLAIN VIEW SEIZURES: If officers see evidence in plain view while conducting the sweep, they may seize it if they have probable cause to believe it is, in fact, evidence of a crime.62 They may also temporarily seize any weapons in plain view.63
MULTIPLE SWEEPS: Officers may sometimes need to make more than one pass through the premises. For example, they might initially look only in obvious places, such as closets, under beds, and behind doors. If no one is found, they might conduct a second pass, looking in less obvious places; e.g., behind furniture, behind curtains, in crawl spaces.
The courts have permitted multiple sweeps, but only when officers were able to explain why more than one pass was necessary. For example, in U.S. v. Paradis officers discovered a gun after they had arrested the suspect and after they had thoroughly swept the premises twice. In ruling that the third pass was unnecessary, the court said:
There was no reason to think that there was another person besides Paradis in the small apartment. At the time the gun was found, the police had already been through the entire apartment. They had been through the living room at least twice (and one or two officers remained there doing paperwork). And they had been through the only bedroom of the unit twice, finding Paradis on the second hunt. Furthermore, by their own testimony the police established that the only logical place someone could hide in the bedroom was under the bed, where they had found Paradis.64
On the other hand, the court in United States v. Boyd upheld a second sweep based largely on testimony from a U.S. Marshal who said that he thought that a second sweep was necessary because, during the first one, his “primary attention was divided between keeping an eye on the two individuals downstairs on the floor and covering [another marshal].”65
NO LEAST INTRUSIVE MEANS REQUIREMENT: A protective sweep will not be invalidated on grounds that officers might have been able to eliminate the threat by some less intrusive means, such as quickly leaving the premises after making the arrest, or guarding the door to a room in which a person was reasonably believed to be hiding.66 Nor will a sweep be deemed unlawful on grounds that officers could have avoided the necessity of a search by waiting to make the arrest outside the premises.67
TERMINATING THE SWEEP: Officers must terminate the sweep after checking all the places in which a person might reasonably be found.68 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.5%3A_Protective_Sweeps.txt |
Consensual encounters may also take place at the doorway of a home.1
While most consensual encounters or “contacts” occur on the streets as a spontaneous response to a situation or circumstance, they may also take place at the suspect’s home. Commonly known as “knock and talks,” these types of contacts are usually employed when officers have reason to believe that a resident is involved in some sort of criminal activity but they lack any other effective means of confirming or dispelling their suspicion. So they visit him at home for the purpose of asking some questions and oftentimes seeking consent to search the premises.2 As the Supreme Court observed, “In situations where the police have some evidence of illicit activity, but lack probable cause to arrest or search, a search authorized by a valid consent may be the only means of obtaining important and reliable evidence.”3
The main thing to remember about knock and talks is that, like all contacts, they must be voluntary, meaning that officers can neither expressly nor impliedly assert their authority. As the Fifth Circuit put it:
The purpose of a “knock and talk” is not to create a show of force, nor to make demands on occupants, nor to raid a residence. Instead, the purpose of a “knock and talk” approach is to make investigatory inquiry or, if officers reasonably suspect criminal activity, to gain the occupants’ consent to search.4
Although knock and talks have been described as a “reasonable investigative tool”5 and a measure that is “firmly rooted” in Fourth Amendment jurisprudence,6 the courts are somewhat leery of them because they take place inside a residence—the most private of all structures protected by the Fourth Amendment. “[W]hen it comes to the Fourth Amendment,” said the Supreme Court, “the home is first among equals.”7
Just as important, the courts are concerned that knock and talks may take on the character of the “dreaded knock on the door” that is prevalent in totalitarian and police states. Addressing this subject, the Sixth Circuit observed that the “right of officers to thrust themselves into a home is a grave concern, not only to the individual but to society which chooses to dwell in reasonable security and freedom from surveillance.”8
Thus, officers who conduct knock and talks must not only understand the rules that cover all types of contacts (which we covered in the lead article), they must also be aware of the additional restrictions that are unique to these sensitive operations.
Making Contact
The manner in which officers make contact with the suspect at the front door is often crucial as it may reasonably be interpreted to mean that he was being detained; i.e., that he “was not at liberty to ignore the police presence and go about his business.”9 Accordingly, the courts are especially alert to the following:
POLITE VS. PERSISTENT KNOCKING: When officers knock on the door or ring the doorbell they must do so in a manner consistent with an ordinary visitor— not as someone who is asserting a legal right to speak with the occupants. This means that continuous or repeated knocking may be deemed a command to open the door which will render the resulting encounter a seizure.10 Thus, in U.S. v. Reeves (admittedly an extreme example) the court ruled that a “reasonable person faced with several police officers consistently knocking and yelling at their door for twenty minutes in the early morning hours would not feel free to ignore the officers’ implicit command to open the door.”11
Similarly, in U.S. v. Jerez 12 sheriff ’s deputies in Wisconsin decided to conduct a knock and talk at a motel room occupied by Jerez, a suspected drug trafficker. But no one answered the door, so they “took turns knocking” for about five minutes. Still no response. So while one deputy began knocking loudly on the window, another “shone his flashlight through the small opening in the window’s drapes, illuminating Mr. Jerez as he lay in the bed.” Eventually, Jerez opened the door and consented to a search which netted cocaine. But the court ruled the entry was not consensual because “[t]his escalation of the encounter renders totally without foundation any characterization that the prolonged confrontation was a consensual encounter.”
Note, however, that the Supreme Court has ruled that neither loud knocking nor a loud announcement will automatically convert the encounter into a seizure. This is mainly because, said the Court, a “forceful knock may be necessary to alert the occupants that someone is at the door” and, unless the officers make a loud announcement, the occupants “may not know who is at their doorstep.” 13
COMMAND TO OPEN DOOR: An encounter at the doorway is plainly not consensual if officers ordered the residents to open the door. As the California Supreme Court put it, “The right to seek interviews with suspects at their homes does not include the right to demand that a suspect open his door.”14 Similarly, the Fifth Circuit observed, “When officers demand entry into a home without a warrant, they have gone beyond the reasonable ‘knock and talk’ strategy of investigation.”15
For example, in ruling that a knock and talk was involuntary, the Ninth Circuit said in U.S. v. Winsor, “[T]he police knocked on the door, identified themselves as police, and demanded that the occupants open the door, and [Winsor] opened the door on command. On these facts, there can be no consent as a matter of law.”16
TIME OF ARRIVAL: The time of the officers’ arrival is significant if it occurred late at night, especially if the lights were out and it appeared the residents were asleep. That is because of the “special vulnerability” of people “awakened in the night by a police intrusion at their dwelling place,”17 and the “peculiar abrasiveness” of such intrusions.18 For this reason, the courts “have recognized that nocturnal encounters with the police in a residence (or a hotel or motel room) should be examined with the greatest of caution.”19 For example, in U.S. v. Jerez (discussed earlier) another reason the knock and talk was deemed unlawful was that the officers had arrived at about 11 P.M. and it appeared the residents had gone to bed; i.e., “the room was quiet; no sounds were heard coming from the room.”20
LOITERING ON THE PROPERTY: Like any other visitor, officers may walk to the front door via normal access routes, then knock or otherwise announce their presence. But if no one answers the door within a reasonable time, they cannot loiter on the property or explore the grounds because such conduct is outside the scope of any implied consent. As the Supreme Court explained, officers are impliedly authorized “to approach the home by the front path, knock promptly, wait briefly to be received, and then (absent invitation to linger longer) leave.”21
NUMBER OF OFFICERS: There is no rule that a maximum of two officers may attempt a knock and talk. But it’s a good rule of thumb. That’s because the more officers at the front door, the more the situation might appear to be a display of police authority.22 As the California Supreme Court observed in People v. Michael, “[T]he appearance of four officers at the door may be a disturbing experience.”23 For example, in U.S. v. Gomez-Moreno the court ruled that officers did not engage in a “proper” knock and talk but instead “created a show of force when ten to twelve armed officers met at the park, drove to the residence, and formed two groups—one for each of the two houses” with a helicopter overhead.”24
To avoid such problems but still address officersafety concerns, some officers may stay hidden. But if a resident happens to see them, the coercion level may increase substantially.25
The Greeting
The manner in which officers greeted the suspect or other person who answered the door is crucial because a cordial and respectful attitude may communicate to him that the officers are merely seeking his cooperation. In contrast, an overbearing or officious attitude will likely be interpreted to mean the officers have a legal right to obtain answers to their questions or conduct a search. For example, in People v. Boyer the court said that “[t]he manner in which the police arrived at defendant’s home, accosted him, and secured his ‘consent’ . . . suggested that they did not intend to take ‘no’ for an answer.”26
Conducting the Investigation
For a discussion of how officers must conduct themselves while questioning the suspect or seeking his consent to search, see “Conducting the Investigation” which begins on page eight in the lead article.
Warrantless Entry to Seize Evidence
There are two situations in which officers who are conducting a knock and talk may enter the premises without a warrant for the limited purpose of seizing or securing evidence.
EVIDENCE IN PLAIN VIEW FROM OPEN DOOR: While speaking with a resident at the front door, officers will sometimes see drugs or other evidence in plain view. Can they enter and seize it without a warrant? The answer is yes if both of the following circumstances existed: (1) they had probable cause to believe the item was evidence of a crime; and (2) an occupant had opened the door voluntarily, not in response to a show of authority. In other words, the officers must not have discovered the evidence—i.e., they must not have obtained “visual access” to it— by means of coercion. Said the Fourth Circuit:
[A] a search occurs for Fourth Amendment purposes when officers gain visual or physical access to a room after an occupant opens the door not voluntarily, but in response to a demand under color of authority.27
On the other hand, if the door was opened voluntarily, a warrantless entry to seize the evidence would be permitted for at least two reasons: (1) an occupant cannot reasonably expect privacy as to something that is obviously evidence of a crime and that he knowingly and voluntarily exposed to the view of officers,28 and (2) the officers might reasonably believe that the suspect would realize they had seen the evidence and that he would immediately attempt to dispose of it if given a chance.29
For example, in U.S. v. Scroger 30 officers in Kansas City, having received reports of drug activity at a certain house, went there at 11 A.M. to conduct a knock and talk. As they were walking up to the front door, they heard someone say “go out the back,” followed by the sounds of someone running. While two officers went to the back, two others went to the front door and knocked. Scroger answered the door, and it was apparent he had been cooking methamphetamine. Among other things, the officers saw “glassware” and detected a “strong odor”—both of which they associated with methamphetamine production. Just then, Scroger tried to slam the door shut, but the officers pushed their way in and took him into custody. After securing the house, they obtained a warrant and ultimately found “a large number of items commonly associated with the clandestine manufacturing of methamphetamine.” Scroger argued that the evidence should have been suppressed because the officers had no right to enter without a warrant or consent. Citing exigent circumstances, however, the court said “[i]t is highly likely that the evidence would have been destroyed or moved if the officers had waited to apprehend Scroger until they had obtained a warrant.”
EXIGENCY BASED ON REASONABLE INFERENCE: Before knocking on the door, officers will sometimes see or hear something that provides them with probable cause to believe the suspect had been alerted to their presence and had started—or would immediately start—to destroy any evidence on the premises. If this happens, the “destruction of evidence” exception to the warrant requirement would apply, in which case the officers could forcibly enter the premises for the limited purpose of securing it pending issuance of a search warrant.31
There is, however, an exception to this rule. Specifically, a warrantless entry will not be permitted if a court finds that the threat to the evidence was fabricated by the officers themselves. How can the courts make this determination? In the past, it was often difficult because the courts would try to determine the officers’ subjective intent. But in 2011 the United States Supreme Court ruled in Kentucky v. King that a threat will be deemed fabricated only if, upon arrival, the officers said or did something that would have caused an occupant of the premises to reasonably believe that the officers were about to enter or search the premises in violation of the Fourth Amendment.32
This means, among other things, that a threat will not be deemed fabricated merely because the officers had somehow alerted the occupants to their presence, even though that might have caused the occupants to attempt to destroy any evidence on the premises. As the Supreme Court observed in King:
[W]henever law enforcement officers knock on the door of premises occupied by a person who may be involved in the drug trade, there is some possibility that the occupants may possess drugs and may seek to destroy them.
But the Court added that such a possibility will not constitute a fabricated exigency unless the officers had expressly or impliedly threatened to enter the premises without a warrant.
13.7: Mincey v. Arizona
PETITIONER RESPONDENT
Rufus Junior Mincey Arizona
LOCATION
University Medical Center
DOCKET NO. DECIDED BY
77-5353 Burger Court
LOWER COURT
Arizona Supreme Court
CITATION
437 US 385 (1978)
ARGUED
Feb 21, 1978
DECIDED
Jun 21, 1978
GRANTED
Oct 17, 1977
ADVOCATES
Richard Oseran for petitioner
Galen H. Wilkes for respondent
Facts of the case
On October 28, 1974, Officer Barry Headricks of the Tucson Metropolitan Area Narcotics Squad allegedly arranged to purchase a quantity of heroin from Rufus Mincey. Later, Officer Headricks knocked on the door of Mincey's apartment, accompanied by nine other plainclothes officers. Mincey’s acquaintance, John Hodgman, opened the door. Officer Headricks slipped inside and quickly went to the bedroom. As the other officers entered the apartment -despite Hodgman’s attempts to stop them -the sound of gunfire came from the bedroom. Officer Headricks emerged from the bedroom and collapsed on the floor; he died a few hours later.
The other officers found Mincey lying on the floor of his bedroom, wounded and semiconscious, then quickly searched the apartment for other injured persons. Mincey suffered damage to his sciatic nerve and partial paralysis of his right leg; a doctor described him as depressed almost to the point of being comatose. A detective interrogated him for several hours at the hospital, ignoring Mincey’s repeated requests for counsel. In addition, soon after the shooting, two homicide detectives arrived at the apartment and took charge of the investigation. Their search lasted for four days, during which officers searched, photographed and diagrammed the entire apartment. They did not obtain a warrant. The state charged Mincey with murder, assault, and three counts of narcotics offenses. Much of the prosecution’s evidence was the product of the extensive search of Mincey’s apartment. Mincey contended at trial that this evidence was unconstitutionally taken without a warrant and that his statements were inadmissible because they were not made voluntarily. In a preliminary hearing, the court found that Mincey made the statements voluntarily.
Question
1. Did the admission of evidence taken during a four-day long warrantless search of Mincey’s residence constitute an unreasonable search or seizure under the Fourth and Fourteenth Amendments?
2. Did the admission of Mincey’s responses to police questioning made while he was a patient in the intensive care unit of a hospital violate his privilege against self-incrimination, rights to counsel and due process under the Fifth, Sixth, and Fourteenth Amendments?
FOR AGAINST
Burger
White
Powell
Stevens
Marshall
Brennan
Stewart
Blackmun
Rehnquist
Conclusion
Yes and yes. In an 8-1 opinion written by Justice Potter Stewart, the Court held that the extensive, warrantless search of Mincey’s apartment was unreasonable and unconstitutional under the Fourth and Fourteenth Amendments. Justice Stewart wrote that warrantless searches were per se unreasonable with a few specific exceptions, and rejected Arizona’s argument that the search of a homicide scene was one of these exceptions. Justice William Rehnquist concurred in part and dissented in part. He agreed that the warrantless search was unconstitutional, but argued that the majority failed to defer to the trial court’s determination that Mincey’s statements were voluntary. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/13%3A_The_Warrant_Process/13.6%3A_Knock_and_Talks.txt |
PETITIONER RESPONDENT
Dethorne Graham M.S. Connor
LOCATION
United States District Court, Western District North Carolina, Charlotte Division
DOCKET NO. DECIDED BY
87-6571 Rehnquist Court
LOWER COURT
United States Court of Appeals for the Fourth Circuit
CITATION
490 US 386 (1989)
ARGUED
Feb 21, 1989
Decided
May 15, 1989
Granted
Oct 3, 1988
ADVOCATES
H. Gerald Beaver on behalf of the Petitioner
Mark Irving Levy on behalf of Respondents
Facts of the case
On November 12, 1984, Dethorne Graham, a diabetic, had an insulin reaction while doing auto work at his home. He asked a friend, William Berry, to drive him to a convenience store in order to purchase some orange juice to counter his reaction. When they arrived at the store, Graham rapidly left the car. He entered the store and saw a line of four or five persons at the counter; not wanting to wait in line, he quickly left the store and returned to Berry’s car. Officer M.S. Connor, a Charlotte police officer, observed Graham entering and exiting the store unusually quickly. He followed the car and pulled it over about a half mile away. Graham, still suffering from an insulin reaction, exited the car and ran around it twice. Berry and Officer Connor stopped Graham, and he sat down on the curb. He soon passed out; when he revived he was handcuffed and lying face down on the sidewalk. Several more police officers were present by this time. The officers picked up Graham, still handcuffed, and placed him over the hood of Berry’s car. Graham attempted to reach for his wallet to show his diabetic identification, and an officer shoved his head down into the hood and told him to shut up. The police then struggled to place Graham in the squad car over Graham’s vigorous resistance. Officer Connor soon determined, however, that Graham had not committed a crime at the convenience store, and returned him to his home. Graham sustained multiple injuries, including a broken foot, as a result of the incident. Graham filed § 1983 charges against Connor, other officers, and the City of Charlotte, alleging a violation of his rights by the excessive use of force by the police.
Question
1. Must Graham show that the police acted “maliciously and sadistically for the very purpose of causing harm” to establish his claim that Charlotte police used excessive force?
2. Must Graham’s claim that law enforcement officials used excessive force be examined under the Fourth Amendment’s “objective reasonableness” standard?
UNANIMOUS
Blackmun
White
Scalia
Rehnquist
O’Conner
Marshall
Brennan
Stevens
Kennedy
Conclusion
No and yes. In a unanimous ruling written by Justice William Rehnquist, the Court held that claims of excessive force used by government officials are properly analyzed under the Fourth Amendment’s “objective reasonableness” standard. The Court vacated the directed verdict and remanded the case to the district court to be decided by that standard. Justice Rehnquist rejected Connor’s argument that “malicious and sadistic” is merely another way of describing conduct that is objectively unreasonable, noting that the subjective motivations of the officers are relevant under the Eighth Amendment, not the Fourth.
14.2: Tennessee v. Garner
PETITIONER RESPONDENT
Tennessee Garner
LOCATION
House where alleged robbery took place
DOCKET NO. DECIDED BY
81-430 Burger Court
LOWER COURT
United States Court of Appeals for the Sixth Circuit
CITATION
471 US 1 (1985)
ARGUED
Oct 30, 1984
DECIDED
Mar 27, 1985
ADVOCATES
W. J. Michael Cody on behalf of appellants in 83-1035
Henry I. Klein on behalf of petitioners in 83-1070
Facts of the case
These are two consolidated cases against different defendants involving the same incident. During a chase, police officer Elton Hymon shot 15-year-old Edward Eugene Garner with a hollow tip bullet to prevent Garner from escaping over a fence. Garner was suspected of robbing a nearby house. Hymon admitted that before he shot he saw no evidence that Garner was armed and "figured" he was unarmed. The bullet hit Garner in the back of the head. Garner was taken to the hospital where he died a short time later.
Garner's father sued seeking damages for violations of Garner's constitutional rights. The district court entered judgment for the defendants because Tennessee law authorized Hymon's actions. The court also felt that Garner had assumed the risk of being shot by recklessly attempting to escape. The U.S. Court of Appeals for the Sixth Circuit reversed, holding that killing a fleeing suspect is a "seizure" under the Fourth Amendment and such a seizure would only be reasonable if the suspect posed a threat to the safety of police officers or the community at large.
Question
Does a statute authorizing use of deadly force to prevent the escape of any fleeing suspected felon violate the Fourth Amendment?
Conclusion
6–3 Decision
Majority Opinion by Byron R. White
FOR AGAINST
Blackmun
White
Powell
Marshall
Stevens
Brennan
Burger
O’Conner
Rehnquist
Yes. In a 6-3 decision, Justice Byron R. White wrote for the majority affirming the court of appeals decision. The Fourth Amendment prohibits the use of deadly force unless it is necessary to prevent the escape of a fleeing felon and the officer has probable cause to believe that the suspect poses a significant threat of violence to the officer or the community. The Tennessee statute was unconstitutional as far as it allowed deadly force to prevent the escape of an unarmed fleeing felon.
Justice Sandra Day O'Connor wrote a dissent stating that the majority went too far in invalidating long-standing common law and police practices contrary to the holding. Chief Justice Warren E. Burger and Justice William H. Rehnquist joined in the dissent. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/14%3A_Police_Use_of_Force/14.1%3A_Graham_v._Conner.txt |
In applying Miranda, one normally begins by asking whether custodial interrogation has taken place.1
It sounds fairly simple: Officers must obtain a waiver and comply with Miranda’s other rules only if they want to “interrogate” someone who is “in custody.”2 As the California Supreme Court put it, “Absent custodial interrogation, Miranda simply does not come into play.”3
The clarity of this rule is, however, illusory. In fact, most officers have learned from experience that determining whether Miranda applies can be a crapshoot. This is mainly because the courts have written hundreds of opinions in which they have defined, redefined, and interpreted the terms “custody” and “interrogation” so as to strip them of their everyday meanings. For example, a suspect who is being questioned in the comfort of his home may be in custody, while most convicted felons who are locked up in state prisons are not. This situation is especially problematic because officers need to know exactly when they need a Miranda waiver and, just as important, when they don’t.
There is, of course, an easy way for officers to avoid this problem: Mirandize every suspect they question. Indeed, that’s how they do it on many television shows. But actor-cops can be confident that actor-crooks will confess if it’s in the script, while real officers know that Mirandizing real crooks often causes them to become more guarded and less likely to spill the beans. After all, those ominous words—“Anything you say may be used against you in court”—were not intended to make suspects feel chatty.4
Consequently, officers often find themselves in a dilemma: If they provide an unnecessary Miranda warning, the suspect may clam up. But if they provide no warning or a tardy one, anything he says may be suppressed.
Fortunately, the situation has improved lately as the courts have made it clear that officers must comply with Miranda only if the surrounding circumstances generated the degree of intimidation that the Miranda procedure was designed to alleviate. As a result, officers can now usually determine when compliance is required if they are familiar with a few rules and concepts which we will cover in this article. We will start with the two types of custody: actual and de facto. Then we will discuss “interrogation” and the custodial situations that are exempt from Miranda.
Actual Custody
It has always been easy to determine when a suspect was in actual custody because it automatically occurs at the moment officers notify him that he is under arrest. As the Court of Appeal observed, “We ordinarily associate the concept of being ‘in custody’ with the notion that one has been formally arrested.”5 Thus, in Berkemer v. McCarty the U.S. Supreme Court summarily ruled that the defendant was in custody “at least as of the moment he was formally placed under arrest.”6
SUSPECT IN CUSTODY FOR ANOTHER CRIME: If the suspect was arrested for one crime, he is in custody even if officers wanted to question him about a crime for which he had not yet been arrested.7 This is because it is custody—not the subject matter of the interview—that generates pressure on a suspect who is being questioned. Thus, if a suspect had been arrested for robbing a gas station, and if officers wanted to question him about a bank robbery, they would need a waiver.
SUSPECT RELEASED: An arrested suspect is no longer in custody after he was released, whether by officers pursuant to Penal Code section 849(b), or after posting bail or obtaining an OR. “Once released,” explained the Court of Appeal, “the suspect is no longer under the inherently compelling pressures of continuous custody where there is a reasonable possibility of wearing the suspect down by badgering police tactics.”8
De Facto Custody
Unlike actual custody, de facto custody is a rather ambiguous concept because it occurs whenever the surrounding circumstances combine to create the “functional equivalent” of an arrest.9 To be slightly more specific, a suspect is in de facto custody if his freedom had been restricted to “the degree associated with a formal arrest.”10 Thus, the Court of Appeal pointed out that the term de facto custody is “a term of art that describes when a citizen has been subject to sufficient restraint by the police to require the giving of Miranda warnings.”11
Rules and principles
While de facto custody is a obscure predicament, it is usually possible for officers to determine whether a suspect is in such a pickle if they keep following rules and principles in mind.
THE REASONABLE PERSON TEST: In determining whether a suspect was in de facto custody, the courts apply the “reasonable person” test, meaning they look to see if a reasonable person in the suspect’s position would have believed he was under arrest.12 If so, he’s in custody. Otherwise, he’s not. “[T]he only relevant inquiry,” said the Supreme Court, “is how a reasonable man in the suspect’s position would have understood his situation.”13
Although the “reasonable person” is a phantom, the courts have equipped him with two significant personality quirks:
1. HE’S OBJECTIVE: In determining whether he is in custody, the reasonable person will consider only the objective circumstances; i.e., the things he actually saw and heard.14
2. HE’S INNOCENT: Being a reasonable person, he was not even remotely involved in the planning or commission of the crime under investigation.15 This is significant because it means he “does not have a guilty state of mind”16 and will therefore view the circumstances much less ominously than the perpetrator.
THE OFFICERS STATE OF MIND
Because the reasonable person will consider only what he saw or heard, it is irrelevant that, unbeknownst to him, the officers believed he was guilty, or that they thought they had probable cause to arrest him, or even that they intended to arrest him at the conclusion of the interview.17
For example, in Berkemer v. McCarty 18 a motorist who had been stopped for DUI contended that he was in custody from the moment the officer saw him stumble from his car. That was because the officer had testified that, based on the suspect’s stumbling and bad driving, he had decided to arrest him. But the Supreme Court ruled that the officer’s plan of action was irrelevant because he never communicated it to the driver.
Similarly, in People v. Blouin 19 an officer went to Blouin’s house to arrest him for possessing a stolen car. But before placing him under arrest, the officer asked him some questions about the car, and Blouin responded by making an incriminating statement. On appeal, Blouin argued that he was in custody when he was questioned because the officer intended to arrest him. But the court ruled it didn’t matter what the officer intended to do because his “intent to detain or arrest, if such did in fact exist, had not been communicated to defendant.”
TEMPORARY RESTRICTIONS
A suspect is not in custody merely because he knew or reasonably believed that he was not free to walk away or move about. This is because a temporary restriction is not nearly as coercive or intimidating as the restrictions imposed on arrestees who will be transported to jail. As the Supreme Court recently observed:
Not all restraints on freedom of movement amount to custody for purposes of Miranda. We have declined to accord talismanic power to the freedom-of-movement inquiry, and have instead asked the additional question whether the relevant environment presents the same inherently coercive pressures as the type of station house questioning at issue in Miranda.20
Thus, the court in People v. Pilster noted that the issue “is not whether a reasonable person would believe he was free to leave, but rather whether such a person would believe he was in police custody of the degree associated with formal arrest.”21 Similarly, in People v. Brown the court said, “Even if we make the assumption that defendant felt that he was not free to leave, we certainly would not be warranted in assuming that he felt he was arrested.”22 This does not mean that freedom to leave is irrelevant. On the contrary, if a reasonable person in the suspect’s position would have believed that he was, in fact, free to leave, the suspect would necessarily not be in custody. Thus, the Second Circuit observed, “It makes sense to begin any custody analysis by asking whether a reasonable person would have thought he was free to leave the police encounter at issue. If the answer is yes, the Miranda inquiry is at an end.”23
It is important not to confuse Miranda custody with Fourth Amendment custody as they are subject to different tests. Specifically, a person is in custody for Fourth Amendment purposes (i.e., “seized”) if he reasonably believed that he was not free to leave.24 But, as noted, such a restriction does not constitute Miranda custody unless it was so severe that it was tantamount to an arrest. For example, if officers question a suspect on the street, and if that person reasonably believed that he was not free to leave, he is deemed “detained.” But, as noted, Miranda custody requires more than a temporary restriction on freedom. Thus, in rejecting the argument that a detainee was in Miranda custody, the court in U.S. v. Luna-Encinas pointed out that, “[e]ven accepting that Luna-Encinas had been ‘seized’ . . . we are convinced that a reasonable person in his position would not have understood his freedom of action to have been curtailed to a degree associated with formal arrest.”25
QUESTIONING CHILDREN: In 2011, the Supreme Court ruled in J.D.B. v. North Carolina that officers who question juvenile suspects must take the suspect’s age into account in determining whether he would have reasonably believed that his freedom had been restricted to the degree associated with an arrest.26 The Court observed that “a reasonable child subjected to police questioning will sometimes feel pressured to submit when a reasonable adult would feel free to go.”
Although it is too early to tell how the courts will interpret J.D.B., there is reason to believe that a minor’s age will have little or no significance when, as is usually the case, the minor was at least 16.27 That is because, as Justice Alito observed in his dissenting opinion (which was cited with apparent approval by the majority), “Most juveniles who are subjected to police interrogation are teenagers nearing the age of majority. These defendants’ reactions to police pressure are unlikely to be much different from the reaction of a typical 18–year–old in similar circumstances.”28 Still, officers who are questioning unarrested minors should consider informing them they are free to leave. See “Questioning in police stations” (“You’re free to leave”), below.
THE TOTALITY OF CIRCUMSTANCES: There are essentially only two circumstances that will automatically render a suspect in custody: (1) pointing a gun at him, and (2) compelling him to go to the police station for questioning. Other than that, it will depend on the totality of circumstances.29 As the Court of Appeal put it, “[W]e look at the interplay and combined effect of all the circumstances to determine whether on balance they created a coercive atmosphere such that a reasonable person would have experienced a restraint tantamount to an arrest.”30
The circumstances that officers are likely to encounter will usually depend on the setting in which the suspect was questioned. For example, while handcuffing is often a significant circumstance when the suspect was detained on the street, it is seldom a factor when the questioning occurred in a police station. We will therefore examine the various situations in which officers question suspects and, for each, the circumstances that commonly exist.
Questioning in police stations
We begin with the place in which most incriminating statements are obtained: the police station. While most of these statements are made by suspects who have been arrested (and who are therefore plainly in custody), officers frequently arrange to question unarrested suspects in police stations, usually because it is convenient and it may give the officers a tactical advantage.
While an interview with an unarrested suspect is not custodial merely because it occurred in a police station,31 it is a relevant circumstance because people who are visiting police stations to discuss their guilt or innocence are more apt to be intimidated by the setting, which is usually “police-dominated” and maybe even “cold” and “hostile.”32 For this reason, officers must not only be alert for coerciveness, they must take affirmative steps to reduce it.
VOLUNTARY APPEARANCE: As noted, it is essential that the suspect voluntarily consented to be questioned at the station. It doesn’t matter whether he accompanied officers in a police car or whether he took the bus—what counts is that he did so freely. As the California Supreme Court pointed out, “A reasonable person who is asked if he or she would come to the police station to answer questions, and who is offered the choice of finding his or her own transportation or accepting a ride from the police, would not feel that he or she had been taken into custody.”33 Similarly, the Ninth Circuit noted, “Where we have found an interrogation non-custodial, we have emphasized that the defendant agreed to accompany officers to the police station or to an interrogation room.”34
For example, in ruling that unarrested suspects were not in custody when questioned in police stations, the courts have noted the following:
• “Beheler voluntarily agreed to accompany the police to the station house.”35
• “The police did not transport Alvarado to the station or require him to appear at a particular time.”36
• “[The officers] requested he come to the station for an interview but did not demand that he accompany them.”37
• “[The officer] asked defendant to accompany him to his office for an interview and said ‘if at any time he needed to come back, we’d drive him back, not to worry about a ride.’”38
But even if the suspect technically consented, his presence at a police station will be deemed involuntary if it was obtained by means of coercion. For example in United States v. Slaight 39 nine officers arrived at Slaight’s home to execute a search warrant. After breaking in “with pistols and assault rifles at the ready,” they asked Slaight if he “would be willing” to follow them to the police station for an interview. He agreed and, in the course of an unMirandized interview, he made an incriminating statement. The Seventh Circuit ruled, however, that the statement was obtained in violation of Miranda because the officers “made a show of force by arriving at Slaight’s house en mass,” and it is “undeniable” that the “presence of overwhelming armed force in the small house could not have failed to intimidate the occupants.”
“YOURE FREE TO LEAVE: While not technically an absolute requirement,40 officers who interview unarrested suspects in police stations should begin by notifying them that they are free to leave.41 That is because such an advisement—commonly known as a Beheler admonition42—is considered “powerful evidence” that the suspect was not in custody.43
There are, however, four things about Beheler admonitions that should be kept in mind. First, they are worthless if it appeared that, despite what the officers said, the suspect was not free to leave. As the Fourth Circuit observed, “Indeed, there is no precedent for the contention that a law enforcement officer simply stating to a suspect that he is ‘not under arrest’ is sufficient to end the inquiry into whether the suspect was ‘in custody’ during an interrogation.”44
Consequently, the courts have ruled that, despite Beheler admonitions, suspects were in custody when the following circumstances existed:
• He was handcuffed.45
• He was kept under guard.46
• An officer told him that he could leave only after he told them the truth.47
• When he asked if he was under arrest, the officer “evaded” the question.48
Note, however, that while the security precautions in place at police stations (such as escorts and doors that lock automatically) would make it impossible for most suspects to leave at will, these are not unusual circumstances and are therefore not a strong indication of custody.49
Second, even though the suspect was told he was free to leave, he will likely be deemed in custody at the point he confessed or otherwise reasonably believed that the officers had probable cause to arrest him and therefore he “couldn’t have believed they would actually let him go.”50 (This subject is also discussed in the section “Tone of the interview,” below.)
Third, it may be necessary to provide multiple Beheler advisories if the interview had become lengthy, especially if it was also accusatory. As the court said in People v. Aguilera, “[W]here, as here, a suspect repeatedly denies criminal responsibility and the police reject his denials, confront the suspect with incriminating evidence, and continually press for the ‘truth,’ [a Beheler admonition] would be a significant indication that the interrogation remained non-custodial.”51
Fourth, it is best to tell the suspect that he is free to leave, as opposed to saying he is not under arrest.52 This is because a suspect who is told he is free to leave will necessarily understand that he is not under arrest, while a suspect who is told he is not under arrest will not necessarily understand that he is free to leave. Thus, the Eighth Circuit said that telling a suspect she is free to leave “weighs heavily in favor of noncustody. However, when officers inform a suspect only that she is not under arrest, [this circumstance] is less determinative in favor of noncustody.”53
QUESTIONING IN INTERVIEW ROOMS: Officers who
question unarrested suspects in police stations will usually do so in an interview room. This is because most interview rooms are quiet and free from distractions, and also because many are equipped with concealed microphones and cameras.
Interview rooms are, however, considered an “inherently coercive environment”54 because the suspect is “cut off from the outside world”55 and because he is in a place that is almost always stark, windowless, and confining.56 In fact, the Supreme Court in Miranda v. Arizona said “it is obvious that such an interrogation environment is created for no purpose other than to subjugate the individual to the will of his examiner.”57
For these reasons, the fact that the suspect was questioned in an interview room is a circumstance that is relevant in determining whether he was in custody.58 It is not, however, a significant circumstance, especially if the suspect was told he was free to leave and there were no contrary indications. Thus, in Green v. Superior Court the court pointed out, “Notwithstanding the lock on the interview room door, the evidence does not compel the conclusion that defendant could not have left whenever he had wanted during the interview.”59
It should also be noted that officers might be able to reduce the coercive nature of an interview room by, for example, explaining to the suspect that he was being questioned there because it is quiet or, as the officers did in People v. Moore, by placing an object next to the door “to keep it from closing and locking.”60
THE TONE OF THE INTERVIEW: The officers’ demeanor and the general atmosphere of the interview are especially important because an aggressive or confrontational interview may send the message that the officers have probable cause to arrest. On the other hand, the fact that officers appeared to be merely seeking information from the suspect is consistent with the notion that he was free to leave. For example, in ruling that suspects were not in custody, the courts have noted the following:
• “Instead of pressuring Alvarado with the threat of arrest and prosecution, [the officer] appealed to his interest in telling the truth and being helpful.”61
• “These questions were nonaccusatory, and defendant was largely permitted to recount his observations and actions through narrative.”62
• “[T]he questions focused on information defendant had indicated he possessed rather than on defendant’s potential responsibility for the crimes.”63
• “[T]he tone of the officers throughout the interview was courteous and polite” and they did not inform him that they “considered him to be guilty, or that they had the evidence to prove his guilt in court.”64
• The officer “conducted his inquiry in a conversational tone, and there is no evidence he posed confrontational questions or pressured the defendant in any manner.”65
This does not mean that stationhouse interviews will become custodial if officers informed the suspect that he had become the “focus” of their investigation, or because they told him about the incriminating evidence they had obtained to date. As the Supreme Court observed, “Even a clear statement from an officer that the person under interrogation is a prime suspect is not, in itself, dispositive of the custody issue, for some suspects are free to come and go.”66
As we will discuss later, informing a suspect of the evidence that tends to incriminate him does not ordinarily constitute “interrogation.” And it is not likely to render him in custody if it was done in an informative—not accusatorial—manner. Thus, in In re Kenneth S.67 the court said, “The fact that Detective Carranza told respondent that he had information that respondent was involved in the robbery was insufficient by itself to constitute custody and to countervail these other factors.” Similarly, the courts have ruled that an interview was not rendered custodial merely because officers told the suspect they had information that he was involved in the robbery under investigation,68 that his fingerprints were found at the scene of a burglary,69 or that his suspected accomplice had named him as the perpetrator.70
While merely informing the suspect of the evidence of his guilt is not apt to render an interview custodial, saying or implying that this evidence constitutes grounds for an immediate arrest will likely do so. For example, in People v. Boyer 71 the defendant accompanied officers to the Fullerton police station to talk about a double murder he was suspected of having committed. In the course of the interrogation, which the court described as “intense,” the officers told Boyer that the victims’ son had identified him as the killer, that the officers could prove he did it, and that he was “gonna fall.” Boyer asked several times whether he was under arrest, but the officers “evaded the questions” in hopes of “prolonging the interview.” He later confessed, but the court ruled his confession was obtained in violation of Miranda because, “in an intense interrogation spanning nearly two hours, they led the defendant to believe . . . they had the evidence to prove his guilt in court. [A] reasonable person in such circumstances would only have considered himself under practical arrest.”
Similarly, in People v. Aguilera 72 San Jose police officers received a tip that Aguilera was involved in a gang-related shooting. So they went to his house and obtained his consent to accompany them to the station to talk about it. At the beginning, Aguilera claimed he was not involved in the shooting, at which point the officers called him a liar, said his story was “bullshit,” accused him of “fabricating an alibi,” and told him that his fingerprints had been found on one of the cars used by the shooters. After the interview progressed in this manner for a while, Aguilera abandoned his story and confessed. But the court ruled that his confession should have been suppressed because he was in custody. Among other things, the court noted that the interrogation “was intense, persistent, aggressive, confrontational, accusatory, and, at times, threatening and intimidating.” The court added, “Although the officers’ tactics and techniques do not appear unusual or unreasonable, we associate them with the full-blown interrogation of an arrestee.”
LENGTH OF THE INTERVIEW: Although the courts often note the length of the interview, this is seldom a significant factor unless its duration or intensity were excessive. Thus, in People v. Morris the California Supreme Court noted that “[t]he interview was fairly long—one hour and 45 minutes—but not, as a whole, particularly intense or confrontational.”73 Similarly, in U.S. v. Bassignani the Ninth Circuit noted that, while a two and a half hour interrogation was “at the high end” of situations which had been deemed noncustodial, “this was not a marathon session designed to force a confession, and we therefore accord less weight to this factor.”74
Questioning detainees
Another setting in which officers frequently question suspects is the street. And if, as is often the case, the suspect had been detained, the officers will need to know whether a Miranda waiver is required. Here, the rule is straightforward: Although detainees are aware that they are not free to leave or move about, they are not in custody for Miranda purposes if the restraint on their freedom was apparently temporary and “comparatively nonthreatening.”75 As the Court of Appeal put it, “Temporary detention only slightly resembles [Miranda] custody, ‘as the mist resembles rain.’”76 A detention will, however, become custodial if the detainee was “subjected to treatment that rendered him ‘in custody’ for practical purposes.”77 This ordinarily occurs if the questioning had “ceased to be brief and casual” and had become “sustained and coercive,”78 or if the detainee’s freedom had been “curtailed to a degree associated with formal arrest.”79
HANDCUFFS: When officers arrest a suspect, one of the first things they will usually do is handcuff him. And because handcuffing is a “distinguishing feature”80 or “hallmark”81 of an arrest, it has been argued that handcuffing a detainee necessarily renders him in custody for Miranda purposes.
The courts have, however, consistently rejected these arguments on grounds that, because custody depends on an examination of the totality of circumstances, there may be offsetting circumstances that would have communicated to the detainee that, despite the handcuffs, he was not under arrest. As the Court of Appeal explained, “Police officers may sufficiently attenuate an initial display of force, used to effect an investigative stop, so that no Miranda warnings are required.”82
While there are no required circumstances, the cases seem to indicate that all of the following should exist:
1. “YOU’RE NOT UNDER ARREST”: At or near the time the detainee was handcuffed, the officers told him that he was not under arrest.
2. EXPLAINING THE HANDCUFFS: The officers also explained why he was being handcuffed; e.g., it was merely a temporary measure while they conducted further investigation; e.g., searched a vehicle, ran a warrant check, interviewed witnesses or other suspects. As the Court of Appeal noted, “[B]rief handcuffing of a detainee would look less like a formal arrest if the interviewing officer informed the detainee that handcuffs were temporary and solely for safety purposes . . . ”83
3. DURATION OF HANDCUFFING: The detainee was not handcuffed for a lengthy period of time.
4. NO OVERRIDING CIRCUMSTANCES: There were no other circumstances that would have reasonably indicated that, despite the officer’s assurances to the contrary, the suspect was under arrest. For example, in U.S. v. Henley the court ruled that a detainee was in custody for Miranda purposes because he was both handcuffed and placed in the back seat of a patrol car.84
DRAWN FIREARM: A detainee who is questioned at gunpoint is plainly in custody.85 A drawn weapon would, however, have no coercive effect if the detainee did not see it.86 Furthermore, even if a weapon was displayed before the detainee was questioned, he may be deemed not in custody if (1) the officer was justified in drawing the firearm, (2) the weapon was reholstered before the officer questioned the detainee, and (3) there were no other circumstances that reasonably indicated that the detainee was under arrest.87 Officers can further reduce the coercive effect of a drawn firearm if, before they questioned the detainee, they explained why the weapon had been displayed.
KEEP HANDS IN SIGHT: Commanding a detainee to keep his hands in sight is not something that is associated with an arrest (because arrestees are usually handcuffed), and it is therefore not a significant circumstance.88
LENGTH OF THE DETENTION: Because most detentions are fairly brief, this circumstance is seldom noteworthy.89
AFTER PAT SEARCH: A detainee is not in custody merely because officers pat searched him, although it is a relevant circumstance.90
NUMBER OF OFFICERS: Questioning is considered more coercive—and is thus more indicative of custody—if the detainee was confronted by several officers, especially if several officers questioned him.91 Conversely, the Court of Appeal recently observed, “Logically, the fewer the number of officers surrounding a suspect the less likely the suspect will be affected by custodial pressures.”92
For example, in People v. Lopez the Court of Appeal noted the following in ruling that a detainee was not in custody: “While there were four officers present, they did not congregate around defendant but were dispersed among the three suspects. One officer alone approached and questioned the defendant.”93 Similarly, other courts that have addressed this issue have noted that “only two of [the officers] participated in the questioning; the others remained apart,”94 and although the suspect “did encounter multiple agents,” she “was not confronted by them simultaneously.”95
TONE OF THE INTERVIEW: Officers who are questioning a detainee will usually adopt an amicable tone because they are seeking his voluntary cooperation. Accordingly, the tone of most such interviews is seldom coercive. If, however, their questions became accusatory, this would be highly relevant.96 Also see “Questioning in police stations” (Tone of the interview), above.
QUESTIONING IN POLICE CARS: For various reasons, officers will sometimes question detainees in police cars; e.g., it was cold, dark, windy, or rainy outside.97 While this will not render the interview custodial,98 it is a relevant circumstance if the detainee was required to sit in the caged back seat, as opposed to the front passenger seat or a back seat that was not caged.99 Furthermore, a detainee who is questioned behind a cage will almost always be deemed in custody if he was handcuffed.100
“YOURE FREE TO LEAVE: Officers will usually be able to eliminate any coerciveness resulting from a detention by informing the suspect in no uncertain terms that the detention has concluded and that he is now free to leave. After determining that he understands this, officers may seek his consent to answer additional questions; and if he agrees to do so, it is likely that the encounter will be deemed noncustodial. This subject is covered in the section “Questioning in police stations” (“You’re free to leave”), above.
Questioning in the suspect’s home
The least coercive setting in which officers will question a suspect is the suspect’s home.101 As the Sixth Circuit observed in United States v. Panak, a person’s home “is the one place where individuals will feel most unrestrained.”102 For this reason, a Miranda waiver is seldom necessary unless, as we will now discuss, the officers said or did something that dramatically changed the atmosphere.
HANDCUFFING, OVERBEARING CONDUCT: Questioning that occurs in the suspect’s home will be deemed custodial if the officers handcuffed the suspect or otherwise conducted themselves, not as visitors seeking information, but as occupiers of the premises. As the Sixth Circuit explained:
Even when an interrogation takes place in the familiar surroundings of a home, it still may become custodial without the officer having to place handcuffs on the individual. The number of officers, the show of authority, the conspicuous display of drawn weapons, the nature of the questioning all may transform one’s castle into an interrogation cell—turning an inherently comfortable and familiar environment into one that a reasonable person would perceive as unduly hostile, coercive and freedom-restraining.103
That was exactly what happened in Orozco v. Texas 104 when four Dallas police officers went to Orozco’s home at 4 A.M. to question him about a murder that had occurred a few hours earlier. They were admitted into the house by a woman who said that Orozco was sleeping in his bedroom, where upon all four officers entered the bedroom, awakened Orozco, and questioned him in his bed about the murder. They eventually obtained an incriminating statement, but the U.S. Supreme Court ruled that the statement was obtained in violation of Miranda because, although Orozco was “interrogated on his own bed, in familiar surroundings,” the total situation—especially the officers’ overbearing conduct—demonstrated that he was in custody.
Similarly, in People v. Benally 105 two officers in Sunnyvale went to the Benally’s hotel room to question him about a rape that had occurred earlier that evening. One of the officers drew his handgun, opened the door with a passkey and ordered Benally to raise his hands. After determining that Benally was not armed, the officer holstered his gun. Then, without obtaining a Miranda waiver, he questioned him and obtained some incriminating information. But the court summarily ruled the information was obtained in violation of Miranda because the officers’ conduct rendered the encounter custodial.
EXECUTING SEARCH WARRANTS: A suspect’s home is especially likely to be deemed custodial if officers had made a non-consensual entry to execute a search warrant or conduct a parole or probation search. This is mainly because the officers will usually have taken complete control of the home— and everyone in it—for purposes of officer safety. For example, in ruling that in-home questioning of an unarrested suspect was custodial after officers entered to execute search warrants, the courts have noted the following:
• “[N]ine officers drove up to the house, broke in with a battering ram, strode in with pistols and assault rifles at the ready, and when they found [the suspect] naked in his bed ordered him in an authoritative tone and guns pointed at him, to put his hands up.”106
• “Craighead’s home had become a police-dominated atmosphere. Escorted to a storage room in his own home, sitting on a box, and observing an armed guard by the door, Craighead reasonably believed that there was simply nowhere for him to go.”107
• The suspect’s house “was inundated” with over 23 FBI agents, and the suspect “was awakened at gun point and guarded at all times.”108
• In contrast, the courts have noted the following in ruling that questioning by officers during the execution of search warrants was not custodial:
• An FBI agent told the suspect that he “was not under arrest and was free to leave” and there were no contradictory circumstances.109
• “[T]he officers specifically informed Sutera that he was not under arrest, that he did not have to answer their questions, and that he was free to move around the apartment or leave anytime he wished.”110
• “[T]here is nothing to suggest that the officers acted in a hostile or coercive manner.”111
Questioning in prisons
Officers will sometimes want to question state prison inmates about crimes that occurred before they were incarcerated; and correctional officers will often want to question them about crimes that occurred inside the facility, such as battery on another inmate or possession of drugs or other contraband. At first glance, it might seem that anyone who is locked up in prison would automatically be in custody. But upon closer examination, it becomes apparent they are not.
The reason is that a prison inmate who is questioned by officers is not nearly as vulnerable to pressure as a person who had recently undergone the “sharp and ominous”112 change of circumstances that results from an arrest. As the Supreme Court recently explained in Howes v. Fields, “[T]he ordinary restrictions of prison life, while no doubt unpleasant, are expected and familiar and thus do not involve the same inherently compelling pressures” as those that result when “a person is arrested in his home or on the street and whisked to a police station for questioning.”113 Furthermore, the Court pointed out that, unlike arrestees, prison inmates know that, regardless of what they say to the officers who question them, they will not be walking out the prison gates when the interview is over and, thus, they are “unlikely to be lured into speaking by a longing for prompt release.”
For these reasons, the Court ruled that prison inmates are in custody only if they were questioned under circumstances that presented “the same inherently coercive pressures as the type of station house questioning at issue in Miranda.”114 In other words, inmates will be deemed in custody only if they were subjected to pressures and restrictions on their freedom above and beyond those which are inherent in the facility. Or, as the Ninth Circuit explained in a case that anticipated Fields:
In the prison situation [Miranda “custody”] necessarily implies a change in the surroundings of the prisoner which results in an added imposition on his freedom of movement. Thus, restriction is a relative concept, one not determined exclusively by lack of freedom to leave. Rather, we look to some act which places further limitations on the prisoner.115
Accordingly, interviews with prison inmates have been deemed noncustodial when all of the following circumstances existed:
• “YOU CAN RETURN TO YOUR CELL”: The inmate was told that he could leave the room or return to his cell whenever he wanted. This is the “most important” circumstance.116
• NO HANDCUFFS: The inmate was placed in handcuffs.
• TONE OF THE INTERVIEW: The interview was neither lengthy nor highly accusatorial.
• LOCATION OF INTERVIEW: The interview took place in familiar or comfortable surroundings, such as a conference room or library.117
For example, in United States v. Menzer the court ruled that an inmate who was questioned by FBI agents about child molesting allegations was not in custody because:
[T]he defendant voluntarily appeared at the interviews, he was not restrained in any manner, the room was well lit, there were two windows exposing the interview room to the prison administrative office area, the door to the interview room was unlocked and the defendant was told by [an FBI agent] that he was free to leave at any time.118
Questioning in jails
Unlike state prisoners, many jail inmates have not been incarcerated long enough for the “ordinary restrictions” to have become “expected and familiar.”119 Thus, to determine whether a jail inmate is in custody for Miranda purposes, officers must first consider whether he was a timeserver or pretrial detainee.
TIME-SERVERS: Because inmates who are serving a sentence in jail have ordinarily been incarcerated throughout the time that was necessary to adjudicate their cases (usually several months or even years), most of them are not automatically in custody, which means their status will depend on the circumstances pertaining to interviews in prisons; e.g., whether they were told they could return to their cells whenever they wanted.
UNSENTENCED INMATES: It is more difficult to determine the custody status of unsentenced detainees because the length of their incarceration may vary from a few hours to several years. Consequently, officers must consider the following circumstances:
LENGTH OF INCARCERATION: The length of the inmate’s incarceration is a significant circumstance because the longer the stay the more the jailhouse restrictions would have become expected and familiar. It follows that if the inmate had been recently booked or had otherwise not yet settled into a routine, he would likely be deemed in custody regardless of the surrounding circumstances. As for detainees who have been awaiting trial for months or years, it would seem that they are not automatically in custody, and that their custody status would therefore depend on an analysis of the circumstances discussed in the section on prison interviews.
There is, in fact, a pre-Fields California case— People v. Macklem—in which the Court of Appeal ruled that an unsentenced detainee was not “in custody” for Miranda purposes when he was questioned about a jailhouse assault.120 The court’s analysis in Macklem was almost identical to that of the Court in Fields, including the Macklem court’s observation that the defendant was not handcuffed and “was given the opportunity to leave the room if he requested to do so.”
PRIOR INCARCERATIONS: It is arguable that an unsentenced inmate’s status would also depend on whether he had been previously incarcerated in the facility and, if so, the amount of time he had spent there. That is because frequent-flyers may view their local jail as a home away from home.
SAME OR DIFFERENT CRIME: The fact that the inmate was questioned about a crime unrelated to the one for which he had been incarcerated is relevant because a reasonable person in his position would know that the officers who were questioning him did not have the power to release him; i.e., he “is unlikely to be lured into speaking by a longing for prompt release.”121
Questioning in other places
Questioning that occurs in the following places is not inherently coercive and is therefore not apt to render an interview custodial:
public places,122 ambulances,123 hospitals,124 probation and parole offices,125 the suspect’s workplace.126
As for courtrooms, a defendant or witness who is questioned in open court is not in custody for Miranda purposes even if he was incarcerated at the time. As the Ninth Circuit observed, “Cross-examination by a prosecutor, conducted in public and in the presence of both judge and jury, is hardly tantamount to custodial questioning by the police.”127
Finally, it should be noted that, regardless of where the suspect was located when he was questioned, he will not be in custody if the officer was talking to him over the telephone. This is because the suspect can terminate the conversation by simply hanging up. As the California Supreme Court observed in People v. Mayfield, “[A]n officer who is talking to a suspect under these conditions is not physically in the suspect’s presence and thus lacks immediate control over the suspect, who retains a degree of freedom of action inconsistent with a formal arrest.”128
“Interrogation”
Even if a suspect was in custody, a Miranda waiver is not required unless officers planned to immediately “interrogate” him. “It is clear,” said the Supreme Court, “that the special procedural safeguards outlined in Miranda are required not where a suspect is simply taken into custody, but rather where a suspect in custody is subjected to interrogation.”129 What, then, is “interrogation”?
Actually, there are two types: direct and indirect. Direct interrogation is simply any request for information about the crime that the officers are investigating; e.g., “What did you do with all the money, Mr. Madoff?” 130 In contrast, indirect interrogation, also known as the “functional equivalent” of interrogation, is broadly defined as any “practice that the police should know is reasonably likely to elicit an incriminating response.”131 Not surprisingly, almost all of the litigation in this area pertains to indirect interrogation.
General principles
In determining whether officers engaged in indirect interrogation the courts apply the following principles:
REASONABLY LIKELY: Indirect interrogation does not result merely because there was a “possibility” that the officer’s words would have prompted the suspect to make an incriminating statement, or because the officer hoped they would. Instead, it results only if the officer knew or should have known that an incriminating response was reasonably likely. As the California Supreme Court put it:
Not every question directed by an officer to a person in custody amounts to an “interrogation” requiring Miranda warnings. The standard is whether under all the circumstances involved in a given case, the questions are reasonably likely to elicit an incriminating response from the suspect.132
LINK BETWEEN QUESTION AND CRIME: A question is not apt to constitute interrogation unless there was some factual link between it and the crime under investigation.133
THE OFFICERS INTENT: If officers intended to elicit an incriminating statement, their words would probably be deemed interrogation because they would have known that an incriminating response was reasonably likely.134 On the other hand, the fact that officers had no such intent is irrelevant if an incriminating response was reasonably likely.135
UTILIZING INTERROGATION TACTICS: Utilizing interrogation tactics such as “good cop-bad cop” would likely constitute interrogation because the objective is to elicit an incriminating information and, therefore, an incriminating response would have been reasonably foreseeable.136
EXPLOITING VULNERABILITIES: Exploiting a suspect’s weaknesses, fears, or other vulnerabilities to obtain a statement—especially extreme vulnerabilities—is likely to render an interview custodial because an incriminating response is reasonably likely. In the words of the Supreme Court, “Any knowledge the police may have had concerning the unusual susceptibility of a defendant to a particular form of persuasion might be an important factor in determining whether the police should have known that their words or actions were reasonably likely to elicit an incriminating response.”137
In the discussion that follows, we will show how the courts apply these principles in determining whether an officer’s words or conduct constituted interrogation.
Accusations
Accusing a suspect of having committed the crime under investigation will almost always constitute interrogation because of the likelihood he will respond by saying something incriminating. That’s what happened in In re Albert R. when an officer, having just arrested Albert for car theft, said “[t]hat was sure a cold thing you did to [your friend], selling him that hot car.” Albert responded, “Yes, but I made the money last.” Not surprisingly, the court suppressed the admission on grounds that the officer’s words constituted interrogation.138
Interrogation will also result if officers arranged for someone else to make the accusation in their presence. For example, in People v. Stewart 139 an officer brought two robbery suspects, Clements and Stewart, into an interview room and instructed Clements to read aloud his written confession in which he also implicated Stewart. At Stewart’s trial, prosecutors were permitted to present evidence that Stewart did not deny Clements’ allegation, but the court ruled this violated Miranda because Clements made the accusation while acting as a surrogate interrogator.
Confronting with evidence
In contrast to accusations, merely informing the suspect of the evidence of his guilt will not constitute interrogation if it was done in a brief, factual, and dispassionate manner.140 As the Ninth Circuit observed in United States v. Hsu:
[O]bjective, undistorted presentations by the police of the evidence against a suspect are less constitutionally suspect than is continuous questioning because the risk of coercion is lessened when information is not directly elicited.141
For example, in People v. Gray an officer who had just arrested Gray for murder, told him of “considerable evidence pointing to his involvement in the death.” In ruling that this did not constitute interrogation, the court pointed out that “the transcript reflects that [the officer’s] recitation of the facts was accurate, dispassionate and not remotely threatening.”142
Similarly, in Shedelbower v. Estelle officers were about to leave an interview room after the defendant, a suspect in a rape and murder, had invoked his Miranda right to counsel. As they were gathering up their papers, one of them informed Shedelbower that his accomplice had also been arrested, and that one of his victims had identified his photo as one of the men who had raped her and murdered her friend. In ruling the officer’s words did not constitute interrogation, the Ninth Circuit pointed out that they “did not call for nor elicit an incriminating response. They were not the type of comments that would encourage Shedelbower to make some spontaneous incriminating remark.”143
Finally, in United States v. Davis 144 FBI agents arrested the defendant for robbing a bank. During questioning, Davis invoked his right to remain silent, at which point an agent showed him a surveillance photo of the robbery. As Davis studied the photo and noticed the remarkable similarity between his face and that of the robber, the agent inquired, “Are you sure you don’t want to reconsider?” Davis responded, “Well, I guess you’ve got me.” He then waived his rights and confessed. On appeal, the Ninth Circuit ruled that the agent’s act of showing Davis the photo did not constitute continued interrogation because he “merely asked Davis if he wanted to reconsider his decision to remain silent, in view of the picture; the questioning did not resume until Davis had voluntarily agreed that it should.” In a subsequent case in which the court discussed its decision in Davis, it noted that the “key distinction between questioning the suspect and presenting the evidence available against him” was “central” to the decision.145
Interrogation may, however, result if the officer presented the evidence to the suspect in a goading, provocative, or accusatorial manner. For example, in People v. Sims an officer who was questioning a murder suspect described the crime scene “including the condition of the victim, bound, gagged, and submerged in the bathtub, and said to defendant that the victim ‘did not have to die in this manner and could have been left there tied and gagged in the manner in which he was found.’” The California Supreme Court ruled that the officer’s statement constituted interrogation.146
Even a brief comment might constitute interrogation if it was goading. For example, in People v. Davis 147 the defendant was arrested for murdering two people with an Uzi. At the police station, Davis invoked his right to remain silent and was placed in a holding cell. Later that day, a detective entered the cell and the following ensued:
Officer: Remember that Uzi?
Davis: Yeah.
Officer: Think about that little fingerprint on it. We’ll see ya. (Jail door closes.)
In ruling that the detective’s comment constituted interrogation, the court explained that his parting words—“Think about that little fingerprint on [the Uzi]—implied that “defendant’s fingerprint had been found on the Uzi, and thus indirectly accused defendant of personally shooting the victims.”
Other statements of fact
Providing the suspect with other types of information will seldom constitute interrogation if the information was factual and was presented in a businesslike fashion. For example, the following have been deemed not interrogation:
“YOU’RE UNDER ARREST FOR . . . ” : Informing a suspect that he is under arrest for a certain crime or that he would be booked for a certain crime.148
EXPLAINING SUBJECT OF INTERVIEW: Informing a suspect of the nature of the questions that the officers wanted to ask.149
EXPLAINING THE POST-ARREST PROCEDURE: Informing a suspect of the post-arrest procedure; i.e., what’s going to happen next.150
READING SEARCH WARRANT: Reading to the suspect the contents of a warrant to search his home.151 Also note that the Sixth Circuit recently ruled that an officer did not interrogate a suspect by informing him and the other passengers in a vehicle that, because they all denied that the contraband in the vehicle belonged to them, they would all be taken into custody and charged.152
Neutral questions
A “neutral” question is an inquiry that plainly did not call for information about the crime under investigation. Thus, a neutral question will not constitute interrogation even if it produced a confession or admission. Here are some examples:
BOOKING QUESTIONS: Questions that are asked as a matter of routine in conjunction with the booking process are not interrogation. This subject is covered below in the section on Miranda exceptions.
SEEKING CONSENT TO SEARCH: Seeking consent to search for evidence pertaining to the crime under investigation does not constitute interrogation because it essentially calls for a yes or no response.153
QUESTIONING A WITNESS: When officers question a person in custody about a crime for which he is believed to be only a witness, their questions will not constitute interrogation because there is little likelihood that they will elicit an incriminating response.154
Miscellaneous
LECTURES: An officer’s lecture to a suspect or other monologue in his presence may constitute interrogation, especially if it was lengthy, provocative, or goading.155
CASUAL CONVERSATION: Casual conversation or small talk is not apt to be deemed interrogation, especially if it was not a pretext to obtain incriminating information.156
ANSWERING SUSPECTS QUESTIONS: Answering a suspect’s questions about sentencing or other matters is not likely to constitute interrogation if the officer’s answer was brief and to the point.157
REQUESTING CLARIFICATION: If a suspect makes a spontaneous statement or asks a question, it is not interrogation to simply request that he clarify something, or to ask the types of open-ended questions that merely tend to display interest; e.g., Would you repeat that?158
CONVERSATION FILLERS: Using a conversation filler when a suspect is making a statement does not constitute interrogation; e.g., “Yeah,” “I can understand that,” I hear you,” “Would you repeat that?159
QUESTIONS ABOUT HEALTH OR INJURY: Asking a suspect about an injury or some other physical ailment is not apt to be deemed interrogation unless it was a pretext to obtain incriminating information160
RECORDING CONVERSATION BETWEEN SUSPECTS:
Placing suspects together and secretly recording their conversation does not constitute interrogation. Thus, U.S. v. Hernandez-Mendoza the Eighth Circuit ruled that an officer’s “act of leaving the appellants alone in his vehicle, with a recording device activated, was not the functional equivalent of express questioning.”161
Miranda Exceptions
There are three exceptions to the rule that officers must obtain a Miranda waiver before engaging in custodial interrogation: (1) the routine booking question exception, (2) the public safety exception, and (3) the undercover agent exception.
Routine booking questions
When a person is arrested, there are certain questions that officers or jail personnel will ask as a matter of routine, usually in conjunction with the booking process. Such questions will seldom constitute interrogation because an incriminating response is seldom foreseeable. But even if it was foreseeable (e.g., the suspect’s address would be incriminating if drugs had been found there), the response will not be suppressed if the question was “normally attendant to arrest and custody.”162 As we will now explain, there are two types of routine booking questions: (1) questioning seeking basic identifying information, and (2) questions seeking administrative information.
BASIC IDENTIFYING INFORMATION: A Miranda waiver is not required before seeking basic identifying data or biographical information that is needed to complete the booking or pretrial services process; e.g., suspect’s name, gang moniker, address, date of birth, place of birth, phone number, occupation, social security number, employment history, arrest record, parents’ names, spouse’s name.163
BASIC ADMINISTRATIVE INFORMATION: A question may also be covered under the routine booking exception if the following circumstances existed:
1. LEGITIMATE ADMINISTRATIVE PURPOSE: The question sought information that was needed for a legitimate jail administrative purpose.
2. NOT A PRETEXT: The question was not a pretext to obtain incriminating information.164
For example, jail officials may ask an inmate about his gang affiliation in order to keep him separated from members of rival gangs.165 But such questions would not be covered if their objective was to obtain intelligence about gang activities in his neighborhood.166 Nor would the exception apply to questions as to why the arrestee possessed credit cards in various names,167 or how the arrestee had arrived at the house in which he was arrested.168
Two other things should be noted. First, a booking-related question may be deemed pretextual if it was not asked in conjunction with the booking process.169 Second, although some courts have ruled that the routine booking question exception does not apply if the question was reasonably likely to elicit an incriminating response,170 this is illogical. After all, if the exception applied only to questions that were not reasonably likely to elicit an incriminating response, the exception would be superfluous because the question would not constitute interrogation and, therefore, Miranda would not even apply.
The public safety exception
Under Miranda’s public safety exception, officers may question a suspect who is in custody without obtaining a waiver (or after he invoked his right to remain silent or right to counsel) if they reasonably believed that he possessed information that would help save a life, prevent serious injury, or diffuse a serious threat to property.171 The justification for this exception is fairly straightforward: When a substantial threat to people or property could be reduced or eliminated by obtaining information from a suspect who was in custody, it is not in the public interest to require that officers begin the interview by warning him (essentially) that he would be better off if he refused to assist them. As we will now explain, the public safety exception will be applied only if both of the following circumstances existed:
1. THREAT EXISTED: The officers must have reasonably believed that a threat to public safety existed.
2. QUESTIONS REASONABLY NECESSARY: The officers’ questions must have been directed toward obtaining information that was reasonably necessary to eliminate the threat.
THREAT EXISTED: Officers must have reasonably believed that there existed an imminent and serious threat to a person (whether a civilian, an officer, or the suspect) or to property. The following are examples of questions that have satisfied this requirement:
“CARRYING A WEAPON?” Before pat searching an arrested suspect, an officer asked if he was carrying any weapons or sharp objects.172
“WEAPONS NEARBY?” After arresting or detaining a suspect who was reasonably believed to be armed, an officer asked if he had any other weapons nearby.173
DEADLY WEAPON IN A PUBLIC PLACE: Officers reasonably believed that the suspect had recently discarded a deadly weapon in a public place.174
LOCATE MISSING VICTIM: Officers questioned a kidnapping suspect concerning the whereabouts of his victim.175
SUSPECT INGESTED DRUGS: Having probable cause to believe that the suspect had just swallowed one or more rocks of cocaine, a deputy asked if he had, in fact, ingested drugs.176
HOSTAGE NEGOTIATIONS: A police negotiator spoke with a barricaded suspect who was holding a hostage.177
QUESTIONS REASONABLY NECESSARY: As noted, the public safety exception covers only those questions that were reasonably necessary to eliminate the threat.178 As the Court of Appeal observed, the officer’s inquiry “must be narrowly tailored to prevent potential harm.”179 For example, while officers could ask an arrestee if he was carrying a weapon or if he had any sharp objects in his possession, they could not ask “What’s in your pocket?” or “Why are you carrying a gun?”180
The undercover agent exception
The third Miranda exception, the “undercover agent” exception, covers situations in which the suspect doesn’t know that the person who is asking questions is an undercover officer or a police agent.181 In these situations, Miranda does not apply because a suspect who is unaware he is speaking with an undercover officer or agent would not feel the type of coercion that Miranda was designed to alleviate.182 Note, however, that questioning by an undercover agent may violate the Sixth Amendment right to counsel if the suspect had been arraigned on the crime under discussion.183 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/15%3A_5th_Amendment_Protections/15.1%3A_Miranda_-_When_Compliance_Is_Compulsory.txt |
[W]e are steeped in the culture that knows a person in custody has the right to remain silent. Miranda is practically a household word.
—Anderson v. Terhune 1
Miranda has become embedded in routine police practice to the point where the warnings have become part of our national culture.
—Dickerson v. United States 2
Now that the Miranda rights have achieved the status of cultural icons—like Dr. Phil and Oprah—it seems appropriate to ask: Why must officers still advise suspects of these rights and obtain waivers of them before any interrogation? The question is especially apt in light of the Supreme Court’s observation that anyone who knows he can refuse to answer an officer’s questions (i.e., virtually everybody) “is in a curious posture to later complain that his answers were compelled.”3
Take the case of Ralph Nitschmann. An officer in Santa Barbara had arrested him for felony assault and was just starting to Mirandize him when Nitschmann interrupted and said, “I have the right to remain silent, anything I say can and will be used against me in a court of law” and so on. Nitschmann concluded by saying “I know the whole bit” and, to his subsequent chagrin, the court agreed.4
Despite the possibility that Miranda has outlived its usefulness, the Supreme Court is not expected to scrap it anytime soon. Over the years, however, the Court has made Miranda compliance much less burdensome. As it pointed out in 2000, “If anything, our subsequent cases have reduced the impact of the Miranda rule on legitimate law enforcement.”5 For example, as we will discuss in this article, the Court has ruled that waivers may be implied, that the language of Miranda warnings may vary, that waivers need only be reasonably contemporaneous with the subsequent interview, and that pre-waiver conversations with suspects are permissible within fairly broad limits.
We will begin, however, by explaining the most basic requirement: that waivers must be knowing and intelligent.
“Knowing and Intelligent”
Because a waiver is defined as an “intentional relinquishment or abandonment of a known right,”6 the United States Supreme Court has ruled that Miranda waivers must be both “knowing” and “intelligent.”7 While this is a fundamental rule, for various reasons it continues to be a frequent source of litigation.
“Knowing” waivers
A Miranda waiver is deemed “knowing” if the suspect was correctly informed of his rights and the consequences of waiving them.8 Although the courts are aware that most suspects know their Miranda rights, officers are required to enumerate them because prosecutors have the burden of proving such knowledge by means of direct evidence.9 Consequently, officers must inform suspects of the following:
1. RIGHT TO REMAIN SILENT: The suspect must be informed of his Fifth Amendment right to refuse to answer questions; e.g., You have the right to remain silent.
2. “ANYTHING YOU SAY . . . ” The suspect must be informed of the consequences of waiving his rights; e.g., Anything you say may be used against you in court.
3. RIGHT TO COUNSEL: The Miranda right to counsel can be tricky because it has three components: (a) the right to consult with an attorney before questioning begins, (b) the right to have an attorney present while the questioning is underway, and (c) the right to have an attorney appointed if the suspect cannot afford one; e.g., You have the right to talk to a lawyer and to have him present while you are being questioned. If you cannot afford to hire a lawyer, one will be appointed to represent you before any questioning.10
“. . . AND WILL BE USED AGAINST YOU: Officers neednot—and should not—tell suspects that anything they say “will” be used against them. That is because it is plainly not true. After all, many of the things that suspects say to officers during custodial interrogation will not be used by prosecutors or would be irrelevant at trial; e.g., “This coffee sucks.” Consequently, it is sufficient to inform suspects that anything they say “may,” “might,” “can,” or “could” be used against them.11
LANGUAGE MAY VARY: Officers are not required to recite the Miranda warnings exactly as they were enumerated in the Miranda decision or as they appear in a departmental Miranda card. Thus, the U.S. Supreme Court explained that, while the warnings required by Miranda “are invariable,” the Court “has not dictated the words in which the essential information must be conveyed.”12 Instead, officers are required only to “reasonably convey” the Miranda rights.13
USING A MIRANDA CARD: Although the language may vary, it is usually best to read the warnings from a standard Miranda card to make sure that none of the essential information is inadvertently omitted,14 and to help prosecutors prove that the officers did not misstate the Miranda rights.15 As the Justice Department observed in its brief in Florida v. Powell, “[L]aw enforcement agencies have little reason to assume the litigation risk of experimenting with novel Miranda formulations.” Instead, it is “desirable police practice” and “in law enforcement’s own interest” to state warnings with maximum clarity.”16
Similarly, the Court of Appeal noted, “If officers begin to vary from the standard language, their burden of establishing that defendants have been adequately advised before waiving their rights will increase substantially.”17 For example, in Doody v. Ryan the Ninth Circuit invalidated a waiver because an officer’s improvised Miranda warning was converted into a “twelve-page rambling commentary” that was partly “misleading” and partly “unintelligible.”18
Reading from a Miranda card is especially important if the warning-waiver dialogue will not be recorded. This is because officers can usually prove that their warning was accurate by testifying that they recited it from a card, then reading to the court the warning from that card or a duplicate.19
MINORS: Because minors have the same Miranda rights as adults, officers are not required to provide them with any additional information.20 For example, the courts have rejected arguments that minors must be told that they have a right to speak with a parent or probation officer before they are questioned, or that they have a right to have a parent present while they are questioned.21
“YOU CAN INVOKE WHENEVER YOU WANT: Officers will sometimes supplement the basic warning by telling suspects that, if they waive their rights, they can stop answering questions at any time. This is an accurate statement of the law and is not objectionable.22
NO ADDITIONAL INFORMATION: Officers are not required to furnish suspects with any additional information, even if the suspect might have found it useful in deciding whether to waive or invoke.23 As the Supreme Court observed in Colorado v. Spring, “[A] valid waiver does not require that an individual be informed of all information ‘useful’ in making his decision or all information that might affect his decision to confess.”25 For example, officers need not inform suspects of the topics they planned to discuss during the interview,25 the nature of the crime under investigation,26 the incriminating evidence that they had obtained so far,27 the possible punishment upon conviction,28 and (if not charged with the crime under investigation) that their attorney wants to talk to them.29
INCORRECT MIRANDA WARNINGS: If officers misrepresented the nature of the Miranda rights or the consequences of waiving them, a subsequent waiver may be deemed invalid on grounds that it was not knowing and intelligent. For example, in People v. Russo an officer’s Miranda warning to Russo included the following: “If you didn’t do this, you don’t need a lawyer.” This bit of information rendered Russo’s waiver invalid because, said the court, “Russo was left with little choice but to waive the right to counsel in order, in his mind, to maintain the appearance of innocence.”30
UTILIZING DECEPTION: Although officers must correctly explain the Miranda rights, a waiver will not be invalidated on grounds that they had lied to him about other matters. As the U.S. Supreme Court observed, “Ploys to mislead a suspect or lull him into a false sense of security that do not rise to the level of compulsion or coercion to speak are not within Miranda’s concerns.”31 For example, waivers have been deemed knowing and intelligent when officers told the suspect that his victim was “hurt” even though she was dead;32 or when FBI agents told the suspect that they wanted to talk to him about “terrorism” when they actually wanted to question him about child molesting.33
RECORDING WAIVERS: There is no requirement that officers record the waiver process.34 Still, it is usually a good idea because it provides judges with proof of exactly what was said by the officers and the suspect. This was an issue in People v. Gray and the recording disposed of it. Said the court, “Thanks to the professionalism of [the officers] in their taping of the statement, there was little room to argue at trial that the waiver was not complete and unequivocal.”35 In addition, recordings may be helpful in determining whether a suspect waived or invoked because his tone of voice, emphasis on certain words, pauses, and even laughter may “add meaning to the bare words.” 36 Note that the waiver process, as well as the subsequent interview, may be recorded covertly.37
“Intelligent” waivers
Suspects must not only know their rights in the abstract, they must have understood them. This is what the courts mean when they say that waivers must be “intelligent.” 38 As the Court of Appeal put it, “Essentially, ‘intelligent’ connotes knowing and aware.”39 It should be noted that the term “intelligent” is misleading because, as the court pointed out in People v. Simpson, “it conjures up the idea that the decision to waive Miranda rights must be wise. That, of course, is not the idea.”40
EXPRESS STATEMENT OF UNDERSTANDING: Technically, officers are not required to obtain an express statement from the suspect that he understood his rights. That is because the courts must consider the totality of circumstances in making this determination.41 As a practical matter, however, it is dangerous to rely on circumstantial evidence because it creates uncertainty and generates an additional issue for the trial court to resolve. Furthermore, as we will discuss later, an express statement of understanding may be necessary if the suspect’s waiver was implied or if he was mentally impaired. Accordingly, it is best to ask the standard Miranda-card question: Did you understand each of the rights I explained to you? If he says yes, that should be adequate.42
CIRCUMSTANTIAL EVIDENCE OF UNDERSTANDING: If the suspect said he understood his rights, but claimed in court that he didn’t, the court may consider circumstantial evidence of understanding. The circumstances that are most frequently noted are the suspect’s age, experience, education, background, and intelligence, prior arrests, and whether he had previously invoked his rights.43
CLARIFYING THE RIGHTS: If the suspect said or indicated that he did not understand his rights, officers must try to clarify them.44 For example, when asked if he understood his rights, the defendant in People v. Cruz answered “more or less.”45 So the officer “repeated each Miranda admonishment a second time, describing them in less ‘formal’ terms.” The California Supreme Court ruled that such clarification was proper “so as to ensure that defendant could better understand the rights he was waiving.” Note that clarification concerning the right to counsel is frequently necessary because suspects may be confused as to whether a waiver of their right to have counsel present during the interview also constitutes a waiver of their right to be represented by counsel in court.46 The answer, of course, is no.
MENTALLY IMPAIRED SUSPECTS: A suspect who tells officers that he understood his rights may later claim that he really didn’t because his mental capacity was impaired due to alcohol or drugs, physical injuries, a learning disability, or a mental disorder. In most cases, however, the courts rule that waivers of impaired suspects were sufficiently “intelligent” if their answers to the officers’ questions were responsive and coherent. As the California Supreme Court observed in People v. Clark, “[T]his court has repeatedly rejected claims of incapacity or incompetence to waive Miranda rights premised upon voluntary intoxication or ingestion of drugs, where, as in this case, there is nothing in the record to indicate that the defendant did not understand his rights and the questions posed to him.”47 For example, in rejecting arguments that impaired suspects were unable to understand their rights, the courts have noted the following:
UNDER THE INFLUENCE OF DRUGS OR ALCOHOL
• Although the suspect had ingested methamphetamine and cocaine, and had not slept “for days,” his answers were “logical and rational.”48
• When it was tested two hours after the interview ended, his blood-alcohol content was between .14% and .22%. But he “made meaningful responses to questions asked” and “nothing indicated that [he] was anything but rational.”49
• His blood-alcohol content was approximately .21% and the arresting officer testified that his condition was such that he could not safely drive a car but “he otherwise knew what he was doing.” 50
• He was under the influence of PCP but his answers were “rational and appropriate to those questions.” 51
MENTAL INSTABILITY
• Although the suspect had been diagnosed as a paranoid schizophrenic, he “participated in his conversations with detectives, and indeed was keen enough to change his story when [a detective] revealed that the fire originated from inside the car.”52
• He had been admitted to a hospital because he was suffering from acute psychosis and was under the influence of drugs. In addition, he was “sometimes irrational.” Still, he “was responsive to his questioning.”53
• He claimed to be mentally ill, but “coherently responded to all questioning and acknowledged his understanding of his rights.”54
• He had just attempted suicide, but was “alert, and oriented” and “very much aware and awake, and knew what was going on.”55
LEARNING DISABILITY
• His IQ was 47, but he testified he “knew what an attorney was, that he could get one, that he did not have to speak to police unless he wanted to, and that they could not force him to talk.”56
• He “possessed relatively low intelligence” but was “sufficiently intelligent to pass a driver’s test, and to attempt to deceive officers by [lying to them].” 57
• His IQ was “below average” and he suffered from “several mental disorders,” but he said he understood his rights and he was “street smart.”58
• His IQ was between 79 and 85 but he “completed the eighth grade in school. He is able to read and write and was able to work and function in society.”59
It bears repeating that, as some of the courts noted in the above cases, the fact that the suspect attempted to deceive or manipulate officers in the course of an interview is a strong indication that he was sufficiently lucid to appreciate his predicament and formulate a plan (albeit unsuccessful) to outwit them.60
MINORS: The courts presume that minors are fully capable of understanding their Miranda rights.61 As the Court of Appeal observed in In re Charles P., “A presumption that all minors are incapable of a knowing, intelligent waiver of constitutional rights is a form of stereotyping that does not comport with the realities of every day living in our urban society.”62 But because the age, maturity, education, and intelligence of a minor may have a greater affect on understanding than they do on adults, these circumstances may be taken into account.63 It is also relevant that the minor had previous experience with officers and the courts.
For example, in ruling that minors were sufficiently capable of understanding their rights, the courts have noted the following:
• “[H]e was no stranger to the justice system. Defendant had been arrested twice before . . . Both sets of charges led to proceedings in juvenile court, and the second resulted in a commitment to juvenile hall.”64
• “Nelson was 15 years old. He had two prior arrests, the most recent resulting in a several month stay in juvenile hall.”65
• “The minor was an experienced 15-year old at the time of his arrest [and had been] arrested innumerable times in the last couple of years.”66
• “He was a 16 year-old juvenile with considerable experience with the police. He had a record of several arrests. He had served time in a youth camp, and he had been on probation for several years . . . . There is no indication that he was of insufficient intelligence to understand the rights he was waiving, or what the consequences of that waiver would be.” 67
• “Although she was a 16-year-old juvenile, she was streetwise, having run away from home at the ages of 13 and 15, and having traveled and lived on her own in San Francisco and the Southwest. [When questioned about the murder] she lied to the police about her name, age, and family background. She [invoked the right to counsel] when [the investigators] read her her Miranda rights which stopped the interrogation process.”68
Voluntary Waivers
In addition to being “knowing and intelligent,” Miranda waivers must be “voluntary.” This simply means that officers must not have obtained the waiver by means of threats, promises, or any other form of coercion.69 Thus, in rejecting arguments that Miranda waivers were involuntary, the courts have noted the following:
• “[T]here is no evidence that Barrett was threatened, tricked, or cajoled into his waiver.”70
• “No coercive tactics were employed in order to obtain defendant’s waiver of his rights.”71
• “[T]he record is devoid of any suggestion that police resorted to physical or psychological pressure to elicit the statements.”72
• “There is no doubt that Spring’s decision to waive his Fifth Amendment privilege was voluntary. He alleges no coercion of a confession by means of physical violence or other deliberate means calculated to break his will.”73
Two other things should be noted. First, the rule that prohibits involuntary Miranda waivers is similar to the rule that prohibits involuntary confessions and admissions, as both require the suppression of statements that were obtained by means of police coercion. As the California Supreme Court observed, the voluntariness of a Miranda waiver and the voluntariness of a statement are based on “the same inquiry.”74 The main difference is that a waiver is involuntary if officers obtained it by pressuring the suspect into waiving his rights; while a statement is involuntary if, after obtaining a waiver, officers coerced the suspect into making it.
Second, because the issue is whether the officers pressured the suspect into waiving, the suspect’s impaired mental state—whether caused by intoxication, low IQ, young age, or such—is relevant only if the officers exploited it to obtain a waiver.75
Express and Implied Waivers
Until now, we have been discussing what officers must do to obtain a valid waiver of rights. But there is also something the suspect must do: waive them. As we will now discuss, the courts recognize two types of Miranda waivers: (1) express waivers, and (2) waivers implied by conduct.
EXPRESS WAIVERS: An express waiver occurs if the suspect signs a waiver form or if he responds in the affirmative when, after being advised of his rights, he says he is willing to speak with the officers; e.g., “Having these rights in mind, do you want to talk to us?” “Yes.” Note that while an affirmative response is technically only a waiver of the right to remain silent (since the suspect said only that he was willing to “talk” with officers), the courts have consistently ruled it also constitutes a waiver of the right to counsel if, thereafter, the suspect freely responded to the officers’ questions.76
Three other things should be noted about express waivers. First, they constitute “strong proof ” of a valid waiver.77 Second, an affirmative response will suffice even if the suspect did not appear to be delighted about waiving his rights. For example, in People v. Avalos the California Supreme Court rejected the argument that the defendant did not demonstrate a sufficient willingness to waive when, after being asked if he wanted to talk, he said, “Yeah, whatever; I don’t know. I guess so. Whatever you want to talk about, you just tell me, I’ll answer.” 78
Third, if the suspect expressly waived his rights, it is immaterial that he refused to sign a waiver form,79 or that he refused to give a written statement.80
IMPLIED WAIVERS: In 1969 the California Supreme Court ruled that Miranda waivers may be implied under certain circumstances.81 Ten years later, the
U.S. Supreme Court reached the same conclusion.82 And yet, because the language in both decisions was somewhat tentative,83 there was some uncertainty as to what was required to obtain an implied waiver. Consequently, officers would often seek express waivers out of an abundance of caution.
In 2010, however, the U.S. Supreme Court ruled unequivocally in Berghuis v. Thompkins that a waiver will be implied if the suspect, having “a full understanding of his or her rights,” thereafter answered the officers’ questions. Thus, in ruling that Thompkins had impliedly waived his rights, the Court said, “If Thompkins wanted to remain silent, he could have said nothing in response to [the officer’s] questions, or he could have unambiguously invoked his Miranda rights and ended the interrogation.”84 But because did neither of these things, the Court ruled he had impliedly waived his rights.
Consequently, a waiver of both the right to remain silent and the right to counsel will be found if the following circumstances existed:
1. CORRECTLY ADVISED: Officers correctly informed the suspect of his rights.
2. UNDERSTOOD: The suspect said he understood his rights.
3. NO COERCION: Officers exerted no pressure on the suspect to waive his rights.85
Thus, in ruling that the defendant in the postThompkins case of People v. Nelson had impliedly waived his rights, the California Supreme Court observed, “Although [the defendant] did not expressly waive his Miranda rights, he did so implicitly by willingly answering questions after acknowledging that he understood those rights.”86
It should be noted that in People v. Johnson the California Supreme Court indicated that a waiver might be implied only if the suspect freely and unreservedly answered the officers’ questions.88 But the Court in Thompkins seemed to reject this idea, as it ruled that Thompkins had impliedly waived his rights even though he was “largely silent during the interrogation which lasted about three hours.”88
Timely Waivers
The final requirement for obtaining a Miranda waiver is that the waiver must be timely or, in legal jargon, “reasonably contemporaneous” with the start or resumption of the interview.89 This means that officers may be required to obtain a new waiver or at least remind the suspect of his rights if, under the circumstances, there was a reasonable likelihood that he had forgotten his rights or believed they had somehow expired. On the other hand, the California Supreme Court observed that “where a subsequent interrogation is reasonably contemporaneous with a prior knowing and intelligent waiver, a readvisement of Miranda rights is unnecessary.”90
As a practical matter, there are only two situations in which a new warning or reminder is apt to be required. The first occurs if officers obtained a waiver long before they began to question the suspect. This would happen, for example, if an officer obtained a waiver at the scene of the arrest, but the suspect was not questioned until after he had been driven to the police station. If such cases, the suspect may later claim in court that he had forgotten his rights in the interim. (This is one reason why officers should not Mirandize suspects or seek waivers unless they want to begin an interview immediately.) In any event, the most important factor in these cases is simply the number of minutes or hours between the time the suspect waived his rights and the time the interview began.91
The second situation is more common as it occurs when officers recessed or otherwise interrupted a lengthy interview at some point. This typically happens when officers needed to compare notes, consult with other officers or superiors, interview other suspects or witnesses, conduct a lineup, or provide the suspect with a break. Although the Court of Appeal has said that a new Miranda warning “need not precede every twist and turn in the investigatory phase of the criminal proceedings,”92 and although these arguments are frequently contrived, officers need to know what circumstances are relevant so they can determine whether a new waiver may be necessary.
CHANGES IN LOCATION, OFFICERS, TOPIC: In addition to the time lapse between the waiver and the resumption of the interview, the courts will consider whether there was a change in circumstances that would have caused the suspect to reasonably believe that his Miranda rights did not apply to the new situation. What changed circumstances are important? The following, singly or in combination, are frequently cited:
• CHANGE IN LOCATION: The site of the interview had changed during the break.
• CHANGE IN OFFICERS: The preand post-break interviews were conducted by different officers.
• CHANGE IN TOPIC: When the interview resumed after the break, the officers questioned the suspect about a different topic.93
SUSPECTS STATE OF MIND: The suspect’s impaired mental state or young age are relevant as they might affect his ability to remember his rights as the interview progressed and as circumstances changed. Conversely, his mental alertness would tend to demonstrate an ability to retain this information. Thus, in ruling that a waiver was reasonably contemporaneous with an interview that resumed over 30 hours later, the court in People v. Mickle observed that “[n]othing in the record indicates that defendant was mentally impaired or otherwise incapable of remembering the prior advisement.”94
MIRANDA REMINDERS: Even if there was some mental impairment or a change in circumstances, the courts usually reject timeliness arguments if the officers reminded the suspect of his Miranda rights when the interview began or resumed; e.g., Do you remember the rights I read to you earlier? If he says yes, that will usually suffice. For example, in People v. Viscotti the court noted that the defendant “was reminded of the rights he had waived earlier in the day . . . [the officer] clearly implied that those rights were still available to defendant.”95
Hours Location Officers Topics Remind
2 Same Same Same Yes 96
5 Same Different Same No 97
6 Same Same Same No 98
9 Different Same Same No 99
12 Same Same Same Yes 100
15 Same Same Same Yes 101
16 Same Same Same Yes 102
27 Same Same Same Yes 103
36 Same Same Same Yes 104
Before leaving this subject, here are examples of situations in which the courts rejected arguments that the time lapse between the waiver and the beginning or resumption of an interview rendered the waiver untimely:
Pre-Waiver Communications
Before seeking a waiver, officers will almost always have some conversation with the suspect. Frequently, it will consist of small talk to help relieve the tension that is inherent in any custodial interrogation. This is, of course, permissible so long as it was relatively brief. As the Ninth Circuit observed in Clark v. Murphy, “There is nothing inherently wrong with efforts to create a favorable climate for confession.”105
There are, however, two types of pre-waiver communications that may invalidate a subsequent waiver on grounds that they undermined the suspect’s ability to freely decide whether to waive his Miranda rights. They are (1) communications that were part of a so-called “two-step” interrogation process, and (2) communications in which officers trivialized the Miranda protections. Less problematic, but worth discussing, is the subject of “softening up.” Finally, we will cover the common—and usually legal— practice of seeking a waiver after informing the suspect of some or all the evidence that tends to prove he is guilty.
The “Two Step”
In 2004, the U.S. Supreme Court ruled in Missouri v. Seibert that the pre-waiver tactic known as the “two step” was illegal.106 What’s a two step? It was a crafty device in which officers would (step one) blatantly interrogate the suspect before obtaining a Miranda waiver. The officers knew, of course, that any statement he made would be suppressed, but they didn’t care because, if he confessed or made a damaging admission, they would go to step two. Here, the officers would seek a waiver and, if the suspect waived, they would try to get him to repeat his previous statement.107
In most cases, they succeeded because the suspect would think (erroneously) that his first statement could be used against him and, therefore, he had nothing to lose by repeating it. As the Court in Seibert explained, the two step renders Miranda warnings ineffective “by waiting for a particularly opportune time to give them, after the suspect has already confessed.”
Although the Court banned two-step interviews, the justices could not agree on a test for determining whether officers had, in fact, engaged in such conduct. So the lower courts were forced to utilize a seldom-used procedure for resolving these issues.108 And in implementing this procedure, both the California Supreme Court and the Ninth Circuit concluded that the appropriate test focuses on the officers’ intent. Specifically, a two-step violation results if the officers deliberately utilized a twophase interrogation for the purpose of undermining Miranda.109
How can the courts determine the officers’ intent? It is seldom difficult because they will usually have begun by conducting a systematic, exhaustive, and illegal pre-waiver interrogation of the suspect pertaining to the crime under investigation; and the interrogation will have produced a confession or highly incriminating statement which the suspect essentially repeated after he waived his rights.110
Other circumstances that are indicative of a twostep interview include the officers’ act of blatantly or subtlety reminding the suspect during the postwaiver interrogation that he had already “let the cat out of the bag,” the officers’ use of interrogation tactics (e.g., good-cop/bad-cop) during the prewaiver interrogation, and a short time lapse between the preand post-waiver statements.111
Trivializing Miranda
Although there is not much law on this subject, a court might invalidate a waiver if officers obtained it after trivializing the Miranda rights or minimizing the importance of his decision to talk with them. Thus, in People v. Musselwhite the California Supreme Court said:
We agree with the proposition that evidence of police efforts to trivialize the rights accorded suspects by the Miranda decision—by “playing down,” for example, or minimizing their legal significance—may under some circumstances suggest a species of prohibited trickery and weighs against a finding that the suspect’s waiver was knowing, informed, and intelligent.112
The court then ruled, however, that the officer who questioned Musselwhite did not engage in such a practice by merely saying, “[W]hat we’d like to do is just go ahead and advise you of your rights before we even get started and that way there’s no problem with any of it.” In contrast, in Doody v. Ryan the Ninth Circuit ruled that a juvenile’s waiver was invalid because, among other things, the officers had implied that the Miranda warnings “were just formalities.” 113
“Softening up”
Defendants sometimes argue that, although they were not actually coerced or otherwise pressured into waiving their rights, their waiver was nevertheless involuntary because officers engaged in a prewaiver process known as “softening up.” The term comes from the 1977 case of People v. Honeycutt,114 a controversial decision of the California Supreme Court in which a minority of the court opined that a waiver resulting from “softening up” would be invalid. Although the justices neglected to define the term, the conduct they labeled as “softening up” consisted of a lengthy pre-waiver conversation in which the officers suggested to the suspect that it would be advantageous to talk to them because they were on his “side.”
For various reasons, however, California courts have not been receptive to “softening up” claims. One reason is, as the Court of Appeal noted, “Honeycutt involves a unique factual situation and hence its holding must be read in the particular factual context in which it arose.”115 In addition, the Honeycutt court’s discussion of “softening up” was pure dicta (i.e., it was irrelevant to the resolution of the case116) and it was contained in a plurality decision (i.e., a majority of the justices did not endorse it117 ). In addition, Honeycutt was based on the premise that softening-up renders a waiver “involuntary.” But nine years later the United States Supreme Court rejected the idea that involuntariness can result from anything other than coercive police conduct.118 And because it is hardly “coercive” for officers to pretend to be sympathetic to the suspect’s plight, there is reason to believe that Honeycutt is a dead letter.
Putting your cards on the table
Before seeking a waiver, officers may make a tactical decision to disclose to the suspect some or all of the evidence of his guilt they had obtained to date. In many cases, the officers think that the suspect will be more likely to waive his rights if he realized there was abundant evidence of his guilt, or if he thought he could explain it away.
It is, of course, possible that the suspect will respond to such a disclosure by making an incriminating statement. But the courts have consistently ruled that it does not constitute pre-waiver “interrogation,” nor is it otherwise impermissible if the officers did so in a brief, factual, and dispassionate manner.
For example, in People v. Gray119 the officers sought a waiver from a murder suspect after telling him about “considerable evidence pointing to his involvement in the death.” In rejecting an argument that such a tactic had somehow invalidated his subsequent waiver, the court noted that the officer’s recitation of the facts was “accurate, dispassionate and not remotely threatening.”
In addition, having such information may be helpful to the suspect in determining whether or not to waive his rights. Thus, the Ninth Circuit ruled that “Miranda does not preclude officers, after a defendant has invoked his Miranda rights, from informing the defendant of evidence against him or of other circumstances which might contribute to an intelligent exercise of his judgment.”120
For these reasons the courts have ruled that officers did not violate Miranda when, before seeking a waiver, they provided the suspect with the following information:
YOU WERE ID’D: Officers told the suspect that a victim or witness had identified him as the perpetrator.121
WE FOUND THE GUN: An FBI agent told a convicted felon, “We found a gun in your house.”122
WE FOUND THE DOPE: A Border Patrol agent told the suspect that “agents had seized approximately 600 pounds of cocaine and that [he] was in serious trouble.”123
PLAYING WIRETAPPED CONVERSATIONS: Officers played a recording of a wiretapped conversation that incriminated the suspect.124
CHECK OUT THIS PHOTO: An FBI agent showed the suspect a surveillance photo of the suspect as he was robbing a bank.125
YOUR ACCOMPLICE CONFESSED: An officer told the suspect that his accomplice had made a statement and, as the result, the case against the suspect was looking “pretty good.”126
In the next edition: Miranda invocations and post- invocation communications. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/15%3A_5th_Amendment_Protections/15.2%3A_Miranda_Waivers.txt |
PETITIONER RESPONDENT
Miranda Arizona
LOCATION
Phoenix, Arizona
DOCKET NO. DECIDED BY
759 Warren Court
CITATION
384 US 436 (1966)
ARGUED
2/27/66; 2/28/66; 3/1/66
DECIDED
Jun 13, 1966
ADVOCATES
John J. Flynn et. al. for the petitioner, 759
Gary K. Nelson et. al. for the respondent, 759
Thurgood Marshall Solicitor General, for the United States, 761
Telford Taylor for the State of New York as amicus curiae in all cases by special leave of the Court
Duane R. Nedrud for the National District Attorneys' Association, as amicus
Facts of the case
This case represents the consolidation of four cases, in each of which the defendant confessed guilt after being subjected to a variety of interrogation techniques without being informed of his Fifth Amendment rights during an interrogation. On March 13, 1963, Ernesto Miranda was arrested in his house and brought to the police station where he was questioned by police officers in connection with a kidnapping and rape. After two hours of interrogation, the police obtained a written confession from Miranda. The written confession was admitted into evidence at trial despite the objection of the defense attorney and the fact that the police officers admitted that they had not advised Miranda of his right to have an attorney present during the interrogation. The jury found Miranda guilty. On appeal, the Supreme Court of Arizona affirmed and held that Miranda’s constitutional rights were not violated because he did not specifically request counsel.
Question
Do the Fifth Amendment’s protection against self-incrimination extend to the police interrogation of a suspect?
Conclusion
5–4 Decision for Miranda Majority Opinion by Earl Warren
FOR AGAINST
Douglas
Fortas
Warren
Brennan
Black
White
Clark
Stewart
Harlan
The Fifth Amendment requires that law enforcement officials advise suspects of their right to remain silent and to obtain an attorney during interrogations while in police custody. Chief Justice Earl Warren delivered the opinion of the 5-4 majority. The Supreme Court held that the Fifth Amendment’s protection against self-incrimination is available in all settings. Therefore, prosecution may not use statements arising from a custodial interrogation of a suspect unless certain procedural safeguards were in place. Such safeguards include proof that the suspect was aware of his right to be silent, that any statement he makes may be used against him in court, etc.
The Court held that, in each of the cases, the interrogation techniques used did not technically fall into the category of coercive, but they failed to ensure that the defendant’s decision to speak with the police was entirely the product of his own free will. Justice Tom C. Clark wrote a dissenting opinion in which he argued that the majority’s opinion created an unnecessarily strict interpretation of the Fifth Amendment that curtails the ability of the police to effectively execute their duties.
15.4: Escobedo v. Illinois
PETITIONER RESPONDENT
Danny Escobedo Illinois
LOCATION
Chicago Police Department
DOCKET NO. DECIDED BY
615 Warren Court
CITATION
378 US 478 (1964)
ARGUED
Apr 29, 1964
DECIDED
Jun 22, 1964
Facts of the case
Danny Escobedo was arrested and taken to a police station for questioning. Over several hours, the police refused his repeated requests to see his lawyer. Escobedo's lawyer sought unsuccessfully to consult with his client. Escobedo subsequently confessed to murder.
Question
Was Escobedo denied the right to counsel as guaranteed by the Sixth Amendment?
Conclusion
5–4 Decision for Escobedo Majority Opinion By Arthur J. Goldberg
FOR
AGAINST
Douglas
Warren
Black
Goldberg
Brennan
White
Clark
Stewart
Harlan
Yes. Justice Goldberg, in his majority opinion, spoke for the first time of "an absolute right to remain silent." Escobedo had not been adequately informed of his constitutional right to remain silent rather than to be forced to incriminate himself. The case has lost authority as precedent as the arguments in police interrogation and confession cases have shifted from the Sixth Amendment to the Fifth Amendment, emphasizing whether the appropriate warnings have been given and given correctly, and whether the right to remain silent has been waived.
15.5: Rhode Island v. Innis
PETITIONER RESPONDENT
Rhode Island Innis
LOCATION
Police Car
DOCKET NO. DECIDED BY
78-1076 Burger Court
LOWER COURT
Rhode Island Supreme Court
CITATION
446 US 291 (1980)
ARGUED
Oct 30, 1979
DECIDED
May 12, 1980
ADVOCATES
John A. MacFadyen, III Argued the cause for the respondent
Dennis J. Roberts, II Argued the cause for the petitioner
Facts of the case
After a picture identification by the victim of a robbery, Thomas J. Innis was arrested by police in Providence, Rhode Island. Innis was unarmed when arrested. Innis was advised of his Miranda rights and subsequently requested to speak with a lawyer. While escorting Innis to the station in a police car, three officers began discussing the shotgun involved in the robbery. One of the officers commented that there was a school for handicapped children in the area and that if one of the students found the weapon he might injure himself. Innis then interrupted and told the officers to turn the car around so he could show them where the gun was located.
Question
Did the police "interrogation" en route to the station violate Innis's Miranda rights?
Conclusion
6–3 Decision for Rhode Island Majority Opinion by Potter Stewart
FOR
AGAINST
Blackmun
White
Powell
Burger
Stewart
Rehnquist
Marshall
Brennan
Stevens
No. In a 6-to-3 decision, the Court held that the Miranda safeguards came into play "whenever a person in custody is subjected to either express questioning or its functional equivalent," noting that the term "interrogation" under Miranda included "any words or actions on the part of the police (other than those normally attendant to arrest and custody) that the police should know are reasonably likely to elicit an incriminating response from the subject." The Court then found that the officers' conversation did not qualify as words or actions that they should have known were reasonably likely to elicit such a response from Innis. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/15%3A_5th_Amendment_Protections/15.3%3A_Miranda_v._Arizona.txt |
That man there is the one. He’s the one that shot me. Lineup ID, Colman v. Alabama 1
hat man there is in trouble. Big trouble. Even if he didn’t fire the shot, he could easily be found guilty at trial because a witness’s positive identification of a suspect at a lineup or showup is, in the words of the California Supreme Court, “frequently determinative of an accused’s guilt.”2 Or, as the United States Supreme Court put it, “The trial which might determine the accused’s fate may well not be that in the courtroom but that at the pretrial confrontation.”3
One reason that a pretrial identification carries so much weight is that a witness who has picked out a person at a lineup is “not likely to go back on his word later on.”4 In addition, if the witness appears to be credible to the jury, his identification of the defendant is apt to be convincing because a crime victim or witness will seldom have reason to lie about the identity of the perpetrator. And, as if that weren’t enough, prosecutors will usually be permitted to buttress the reliability of the witness’s in-court identification of the defendant by presenting testimony that the witness had also identified him at a lineup or showup when, as is usually the case, the perpetrator’s features would have been fresh in the witness’s memory.5
Simply put, the combination of the witness’s pretrial identification of the defendant and his positive identification in the courtroom generates such convincing force that, from the defendant’s perspective, it is devastating.
This is, of course, a good thing—if the defendant was the perpetrator. But what if he wasn’t? What if the witness was mistaken? And what if he was mistaken because the lineup or showup was intentionally or inadvertently structured so as to induce or otherwise prompt him to identify the defendant? The Supreme Court had this possibility in mind when it observed that “the influence of improper suggestion upon identifying witnesses probably accounts for more miscarriages of justice than any other single factor—perhaps it is responsible for more such errors than all other factors combined.”6
To help prevent this from happening and also to combat the inherent “vagaries of eyewitness identification,”7 the courts require that officers employ certain procedures that are designed to minimize suggestiveness and maximize reliability. As we will discuss later, if officers fail to comply with these requirements, a court may find that the resulting ID was unreliable and, therefore, inadmissible.
There is another reason that compliance is important. Assuming the witness’s ID of the defendant was not so unreliable as to render it inadmissible in court, its impact on jurors will be severely weakened if they think the lineup or showup was unfair. As the Supreme Court cautioned in Manson v. Brathwaite, “Suggestive procedures often will vitiate the weight of the evidence at trial and the jury may tend to discount such evidence.” 8 For these reasons, it is essential that officers understand exactly what they are required to do, and what they are prohibited from doing, when conducting lineups and showups.
In addition to the reliability of the ID, there are several other legal issues that officers and prosecutors commonly confront, and which will also be covered in this article. They include a suspect’s right to have counsel at a lineup and the attorney’s role, what officers can do when a suspect refuses to stand in a lineup, the issuance of Appearance Orders, and defense motions for lineups. But first, the basics.
Types of Lineups and Showups
There are four types of lineups and two types of showups. Although they all serve the purpose of identifying the perpetrator of a crime, they are used in different situations and, as we will discuss later, are subject to different requirements.
LIVE LINEUPS: In common usage, the term “lineup” means a live or “corporeal” lineup in which the suspect is displayed to the witness in the company of five or more people who resemble him; i.e., “fillers” or “foils.” As the Court of Appeal explained, a lineup is “a relatively formalized procedure wherein a suspect is placed among a group of other persons whose general appearance resembles the suspect.”9
To say that lineups are “formalized” simply means they usually take place in lineup rooms in police stations and jails where the suspect and fillers stand on a stage. Bright lights directed at the stage prevent the suspect from seeing the witnesses, which gives them a much-needed sense of security.
Because live lineups require the suspect’s presence, they are usually used only when the suspect is in custody for the crime under investigation or some other crime. If he is not in custody, the usual procedure is to conduct a photo lineup.
RECORDED LINEUPS: In a recorded lineup, officers conduct a live lineup, but without the witness in attendance. Instead, they record the lineup on videotape or digitally, and show it to the witness later. While this procedure is often used when the witness cannot attend a live lineup, it may also be useful if the suspect has a right to have counsel present but an attorney is not available. This is because, as we will discuss later, a suspect does not have a right to counsel when a witness views a recorded lineup.
PHOTO LINEUPS: In a photo lineup, the witness is shown photographs of the suspect and the fillers, usually booking or DMV photos. In most cases, officers will utilize this procedure when it is impractical to conduct a live lineup, usually because the suspect had not yet been arrested.10 A photo lineup may also be necessary if the suspect changed his appearance after the crime occurred, and officers had obtained a photograph of him that better depicted his appearance then.
PHOTO COLLECTIONS: If officers have no suspect, but there is reason to believe that the perpetrator belonged to a certain group, they may show the witness photos of members of that group; e.g., gang books, sexual assault registries, school yearbooks.
VOICE-ONLY LINEUPS: If the witness heard the perpetrator speak, but did not see him, officers may conduct a voice-only lineup in which the witness listens to the voices of the suspect and fillers, but does not see their faces.11 In most cases, the suspect and fillers will say something that the perpetrator said.
Voice-only lineups may be live or prerecorded.
FIELD SHOWUPS: The most common pretrial identification procedure is the field showup in which the suspect is displayed to the witness alone (i.e., without fillers) and the witness is essentially asked, “Is this the perpetrator?” Such a procedure is, of course, highly suggestive, but the courts permit it if there was an overriding reason for not conducting a live or photo lineup.12
In most cases, the overriding reason is that the crime had just occurred, that officers had detained a suspect and they needed to quickly confirm or dispel their suspicion that he was the perpetrator.13 In these situations a showup is justified because, as the Court of Appeal pointed out, “A prompt on-thescene confrontation between a suspect and a witness enables the police to exclude from consideration innocent persons so a search for the real perpetrator can continue while it is reasonably likely he is still in the immediate area.”14 Furthermore, the suggestiveness that is inherent in showups will ordinarily be “offset by the likelihood that a prompt identification within a short time after the commission of the crime will be more accurate than a belated identification days or weeks later.”15
Two other things should be noted about showups. First, there are some procedural restrictions in addition to those relating to suggestiveness. For example, officers must be diligent in conducting showups and they must not transport the suspect to another location for a showup unless he consented or there was good cause. We covered these restrictions in the article “Investigative Detentions” in the Spring 2010 -.
Second, the California Legislature is now considering an addition to the Penal Code which would prohibit officers from conducting showups of suspects if they had probable cause to arrest them. We have discussed some of the problems with such a rule in a comment on page 22 entitled “Showups: Should probable cause make them illegal?”
CONFIRMATORY SHOWUP: Officers have sometimes attempted to confirm that an arrested suspect was the perpetrator by displaying him without fillers, whether live or by photograph. Such a procedure is, of course, highly suggestive.16 For example in the case of People v. Sandoval 17 officers arrested a suspect in a purse snatch that had occurred about 15 minutes earlier. As they drove him to the police station, the victim, who was already seated in a room at the station, was informed by other officers that the suspect “would be brought through the hallway.” As he walked by, the victim identified him, but the court ruled the ID should have been suppressed because this procedure “in effect suggested to the victim that defendant was the robber.” Also see “Pre-lineup photo display” on pages 12-13.
Misidentification: The “Primary Evil”
The main legal issue in most ID cases is whether the investigating officers said or did something that was apt to result in misidentification. This, said the U.S. Supreme Court, is the “primary evil to be avoided.”18 As we will now discuss, the courts try to prevent this from happening by prohibiting testimony pertaining to a pretrial ID unless there was sufficient reason to believe it was reliable.
Before going further, it should be noted that there may be some confusion about this issue. In the past, a witness’s pretrial identification testimony would be suppressed if officers employed procedures that were unduly “suggestive.”19 But this changed in 1977 when the Supreme Court in Manson v. Brathwaite pointed out that suggestiveness, while relevant, does not necessarily lead to misidentification; that the admissibility of a pretrial ID should depend simply on whether it was reliable.20 Said the Court, “Reliability is the linchpin in determining the admissibility of identification testimony.” The question, then, is how can the courts determine whether an ID was sufficiently reliable?
The test for admissibility
To determine whether a witness’s identification of a defendant at a lineup was sufficiently reliable to be admitted into evidence at trial, the courts employ a two-part test. First, they look to see whether the officers utilized a procedure that was unduly suggestive. If it wasn’t, the ID will be admissible.21 If it was, they will determine whether, despite such suggestiveness, the witness’s identification of the defendant was sufficiently trustworthy; i.e., whether, despite such suggestiveness, there was no “substantial likelihood of misidentification.”22 And if the identification was sufficiently reliable, the ID will be admissible; if not, it will be suppressed. (We will discuss how the courts calculate the trustworthiness of an identification later in this article.)
To recap, the test for determining the admissibility of a lineup identification is as follows:
(1) SUGGESTIVE? Was the lineup unduly suggestive?
No: The ID testimony will be admissible. Yes: Proceed to part (2).
(2) TRUSTWORTHY? Despite such suggestiveness, was the witness’s identification of the defendant trustworthy?
No: The lineup results will be suppressed. Yes: The lineup results will be admissible.
Note that if the lineup ID is suppressed, the witness will not be given an opportunity to identify the defendant in court unless prosecutors can prove “by clear and convincing evidence that the in-court identification is based upon observations of the suspect other than the lineup identification.”23
What is suggestiveness?
A lineup or showup will be deemed “suggestive” if it was conducted in a manner that would have communicated to the witness that the suspect was, in fact, the perpetrator. As the Court of Appeal explained, a lineup is suggestive “if it suggests in advance of a witness’s identification the identity of the person suspected by the police.”24 Or, in the words of the California Supreme Court, to warrant the suppression of a witness’s identification of a defendant, “the state must, at the threshold, improperly suggest something to the witness; i.e., it must, wittingly or unwittingly, initiate an unduly suggestive procedure.”25
“UNDULY SUGGESTIVE: As noted, a witness’s identification resulting from a suggestive lineup or showup may be suppressed only if the suggestiveness was “undue” or excessive.26 The reason that suggestiveness, in and of itself, will not result in suppression is that, as the Court of Appeal observed in People v. Perkins, “No identification can be completely insulated from risk from suggestion.”27 For example, field showups are inherently suggestive because the witness views only a single person. And lineups are suggestive because the number of fillers is, by necessity, relatively small; plus it is often difficult to locate fillers who closely resemble the suspect.
MERE SUGGESTIVENESS GOES TO WEIGHT: Any suggestiveness that does not rise to the level of “undue” goes to the weight of the identification, not its admissibility.28
UNINTENTIONAL SUGGESTIVENESS: If the actions of the officers rendered the lineup or showup unduly suggestive, it is immaterial that they did not intend to do so.29
BURDEN OF PROOF: The defense has the initial burden of proving that the lineup or showup was unduly suggestive.30 Furthermore, it must prove such suggestiveness “as a demonstrable reality, not just speculation.”31 If the defense sustains its burden, the prosecution must prove—by clear and convincing evidence—that the identification was nevertheless trustworthy.32
Suggestiveness: Relevant Circumstances
In determining whether a lineup or showup was unduly suggestive, the courts examine the overall procedure—the totality of circumstances.33 As a practical matter, however, the circumstances we discuss next are almost always decisive.
But first it should be noted that, while we included most of these circumstances because of their longstanding influence on the courts, some were added as the result of a report by the California Commission on the Fair Administration of Justice (CCFAJ) entitled “Report and Recommendations Regarding Eyewitness Identification Procedures.” In its report, the CCFAJ suggested that the reliability of lineups and showups would be improved if law enforcement agencies made certain changes in their procedures. Although these suggestions are not mandated by the courts, we have incorporated them in the following discussion, but with notations that they are CCFAJ recommendations. The California Legislature is, however, considering a bill that would require that “law enforcement study and consider adopting” these procedures.34
Similarity between suspect and fillers
While the suspect and the fillers should be similar in age and general appearance, “there is no requirement that [the suspect] be surrounded by people nearly identical in appearance.”35 As the California Supreme Court pointed out, “Because human beings do not look exactly alike, differences are inevitable.”36 Still, officers should attempt to locate fillers who were sufficiently similar in appearance to the suspect so as to enhance the reliability and significance of the witness’s identification. The following comments by the courts illustrate what they look for in evaluating the composition of lineups:
LIVE LINEUPS
• “The five men were of substantially equivalent race, height, and weight.”37
• “The participants all appeared to be of comparable age and of similar build.”38
• “All six participants were bearded and wore identical clothing . . . with one exception, the others resembled defendant very much.”39
• “[T]he men in the lineup were dressed in street clothes consisting of sport shirts and slacks of varying designs and colors. All were black men of similar height and physical build.”40
• Defendant and one of the fillers “had braids or dreadlocks in their hair, while two others appear to have similar type of hair.”41
• “All of the men have a mustache and some have other facial hair. Several have a hairstyle similar to that of defendant.”42
• “[A]ll the participants had different types of facial hair, some with mustaches, some with beards, goatees, etc.”43
PHOTO LINEUPS
• “All [of the five Caucasian women in the photo lineup] are of medium build. The four at the left appear to be of the same general age, that is, between 40 and 50, the tall woman at the extreme right being somewhat younger. None bears a facial resemblance to any of the others. None has extremely distinctive features. The facial idiosyncrasies among the five women are no more marked than those which normally distinguish one person from another.”
• The men depicted in the photographs “are all Caucasian, of a reasonably similar build and within the same age group.”44
• “All of the men depicted in the photographs are White; all have long hair in various shades from blond to brown; and all have beards.”45
• “All of the photographs were of Black males, generally of the same age, complexion, and build, and generally resembling each other . . . . Minor differences in facial hair among the participants did not make the lineup suggestive.”46
• “Each lineup consists of five identically sized photographs of Caucasian males of apparently similar age and with similar facial features. Four of the men . . . appear to have similarly colored light red hair. . . . The color photographs show the subjects against identical blue backgrounds.” 47
• “[A]ll six of the pictures are of Caucasian males in the same age range, with similar skin, eye, and hair coloring. Each photo depicts a subject wearing distinctive glasses. Four of the six photos show men with similar length hair, with two having somewhat shorter hair. All except for one are clean-shaven.”48, 49
VOICE-ONLY LINEUPS: The participants’ voices should be “similar in tone, pitch, volume and accent.”50 Thus, in rejecting an argument that a voice-only lineup was suggestive, the court in People v. Vallez said, “While none of the five imitators was especially talented in impersonating the defendant’s voice, the differences between the voices was not so great as to be unfair or impermissibly suggestive.”51
Did the suspect “stand out?”
If the suspect and fillers were similar in appearance, it is ordinarily immaterial that there was something about the suspect that caused him to stand out. This is because there is usually something about everyone in a lineup that is arguably distinctive; e.g., the tallest, heaviest, best dressed, most uncouth. Consequently, so long as the suspect was not “marked for identification” (discussed later), the fact that there was something distinctive about him will seldom affect the validity of the lineup. As the California Supreme Court explained, the issue is not whether the defendant stood out, but whether he stood out “in a way that would suggest the witnesses should select him.”52 For example, in rejecting arguments that the defendant stood out in this manner, the courts have noted the following:
• While the defendant was the shortest person in the lineup, he was not “significantly” shorter than the others.53
• “[A]lthough defendant was the tallest, all the others were tall as well.”54
• “Although the other men may have been darker in complexion and not as thin, the men in the lineup were sufficiently similar in appearance”55
• “[A]ppellant notes that he was wearing a bright white sweatshirt or sweater. However, so long as the defendant is not alone dressed in a striking manner, there is no need for the police to match outfits of everyone in the lineup anymore than the police are required to match the physical proportions of the other men with scientific exactitude.”56
• “While defendant’s profile is facing the opposite direction from the other five pictures, the point of concern to the witness is the person’s features, not the direction he is facing.”57
• “[A]ny discoloration in defendant’s photograph would not suggest it should be selected.”58
• “[T]he fact defendant’s face has a ‘yellow cast’ is unimpressive as photograph number six has a distinctly ‘red cast,’ number four has an ‘orange cast,’ and others have differing color characteristics.”59
• Although the defendant was the only person in the photo lineup wearing a gold shirt and gold sweater, this clothing “was not similar to that described to the police by [the witness].”60
• “[D]efendant’s tattoo did not make the live lineup impermissibly suggestive. None of the witnesses observed a tattoo on the gunman’s head.”61
In contrast, the court in People v. Carlos 62 ruled that a photo lineup was suggestive because the suspect’s name and ID number were printed below his photo, while none of the other photos were similarly marked. Said the court, “Although the name placement is not quite an arrow pointing to Carlos, it is plainly suggestive.”
LINEUP POSITION: The suspect’s position in the lineup is irrelevant. As the California Supreme Court noted, “[N]o matter where in the array a defendant’s photograph is placed, he can argue that its position is suggestive.”63
NUMBER OF FILLERS: The number of fillers is sometimes noted, but it is seldom a significant circumstance because it is common practice to include at least five. An especially large number of fillers will, of course, reduce any suggestiveness; e.g., witness looked for the perpetrator in gang books, mug books, sexual assault registries, school yearbooks.64
MULTIPLE LINEUP APPEARANCES: A suspect in a lineup may stand out because the witness had seen him in a previous showup or photo lineup. But, so long as there was a legitimate need for multiple lineup appearances, this circumstance will not render an identification unduly suggestive.65
SUSPECT DIRECTS ATTENTION TO HIMSELF: While a suspect will certainly “stand out” if he said or did something that drew attention to himself, the courts will disregard this circumstance in determining whether a lineup or showup was suggestive. As the California Supreme Court observed, the rule prohibiting suggestive lineups and showups “speaks only to suggestive identification procedures employed by the People.”66
For example, in People v. Boyd 67 the defendant claimed that his lineup was unduly suggestive because he “hung his head, moved it back and forth and continued to look at the floor for some seconds.” In rejecting the argument, the Court of Appeal ruled that “a defendant may not base his claim of deprivation of due process in a lineup on his own behavior.” Similarly, in People v. Wimberly,68 a robbery case, the suspect and the fillers in a live lineup were asked to say certain words that the robber had said. Because Wimberly spoke too softly to be heard clearly, an officer asked him to repeat the words. On appeal, Wimberly contended that the officer’s request rendered the subsequent ID suggestive, but the court, citing Boyd, ruled that a suspect may not challenge a lineup “when his own conduct has caused the procedure to be suggestive.”
COVERING UP A DISTINCTIVE FEATURE: In some cases it may be possible to reduce or eliminate any suggestiveness resulting from a single feature by covering it up. For example, in People v. De Santis,69 where the suspect was much shorter than the fillers in a live lineup, officers eliminated the problem by having the suspect stand on some books that were concealed from the witnesses. And in People v. Adams,70 where officers were concerned that the photo of the suspect stood out because of a bandage on his forehead, they covered it up with a piece of paper—then covered all the other photos in the same way. Finally, in People v. De Angelis,71 where the photos of comparable fillers were in black and white, but the only photo of the suspect was in color, the officers reproduced it in black and white.
Was the suspect “marked for identification”?
The most obvious example of a suggestive lineup is one in which the suspect was “marked for identification,” which occurs if both of the following circumstances existed: (1) the witness provided officers with a particular description of the perpetrator or his clothing, or reported that he had a distinctive feature; and (2) the suspect was the only person in the lineup who matched that description or possessed that feature. As the Second Circuit put it, “A lineup is unduly suggestive as to a given defendant if he meets the description of the perpetrator previously given by the witness and the other lineup participants obviously do not.”72
For example, in People v. Caruso 73 two robbery victims described the driver of the getaway car as “big, with dark wavy hair and a dark complexion.” Caruso was arrested and placed in a lineup with four other men. But while he was big, dark, “of Italian descent” with “dark wavy hair,” the other four “were not his size, not one had his dark complexion, and none had dark wavy hair.” In ruling that the lineup was unduly suggestive, the court said, “During the robbery [the witnesses] noted the driver’s large size and dark complexion, and if they were to choose anyone in the lineup, defendant was singularly marked for identification.”
Similarly, in Torres v. City of Los Angeles 74 the court ruled that a suspect was marked for identification in a photo lineup because “only one other photo in the six-pack besides the photo of [the suspect] was of a visibly overweight individual and thus of a person who fit [the victim’s] description.”
The same principle applies to clothing worn by the perpetrator. For example, in Foster v. California 75 the Supreme Court invalidated a lineup because “petitioner stood out from the other two men . . . by the fact that he was wearing a leather jacket similar to that worn by the robber.” And in People v. Ware 76 the court ruled that a photo lineup was suggestive because the defendant was “the only person in the photos wearing a blue denim jacket of the type [that the victim] reported her assailant was wearing.”
On the other hand, if the feature was not particularly distinctive, or if it was shared by other fillers, the courts will usually admit the ID and let the jury decide its weight. Thus, in ruling that the defendant was not marked for identification, the courts have noted the following:
• “While it is true that defendant’s photograph has the mustache with the most pronounced gap in the center [the perpetrator had a gapped mustache], others of the photographs have mustaches with at least slight gaps.”77
• “The mere fact that defendant was wearing the same color pants worn by the robber did not make the lineup unfair.”78
• Although the perpetrator wore a bandana, and although the defendant was the only person in the photo lineup who wore a bandana, “two of the other photos showed persons with different headgear.”79
• While the man who robbed a liquor store was wearing a blue jacket, and although the defendant was wearing a blue jacket at the lineup, all of the eight men in the lineup were wearing similar blue jackets.80
Pre-lineup communications
A lineup or showup that was otherwise fair may be deemed suggestive if officers said or did something beforehand that would have prompted the witness to select the suspect. As the United States Supreme Court observed, “Persons who conduct the identification procedure may suggest, intentionally or unintentionally, that they suspect the witness to identify the accused. Such a suggestion, coming from a police officer or prosecutor, can lead a witness to make a mistaken identification.”81
PROVIDING SUGGESTIVE INFORMATION: Officers must, of course, say nothing to the witness that could be reasonably interpreted as directing attention to the suspect.82 Thus, the Court of Appeal warned against “[s]uggestive comments or conduct that single out certain suspects or otherwise focus a witness’s attention on a certain person in a lineup.”83 For example, in Torres v. City of Los Angeles 84 the court ruled it was suggestive to tell the witness that officers had “possibly identified the 15 to 16 year-old chubby boy” who was involved in a drive-by murder, and there were only two overweight boys in the lineup, one of whom was the defendant.
IMPLYING A SUSPECT OR PERPETRATOR IS IN LINEUP: It has been argued that officers must not even inform a witness that they have arrested someone, or that one of the people in the lineup is a “suspect.” While officers should avoid suggesting that the perpetrator is in the lineup (“Which one of these guys did it?”85), the courts have consistently rejected arguments that it was unduly suggestive to inform a witness that someone in the lineup was a suspect. This is because witnesses who are asked to view a lineup will naturally assume that officers did not grab six people off the street at random in hopes that one of them might have been the perpetrator.86 Still, when suggestiveness is an issue, the courts often note, at least in passing, whether the officers did or did not tell the witness that they had a “suspect” or that a “suspect” was in the lineup.87
“ANOTHER WITNESS MADE AN ID”: If another witness had previously identified someone in a lineup, officers should keep this confidential as it may be viewed as pressuring the witness to make an identification.88
CAUTIONARY INSTRUCTIONS: It is considered standard procedure for officers to help reduce any inherent suggestiveness by giving the witness certain information and instructions.89 The following are fairly common:
LINEUPS
• The perpetrator may or may not be in the lineup. (Or, do not assume that we have identified the perpetrator merely because we are asking you to attend a lineup.)
• You are not obligated to identify anyone.
• Do not discuss your case with other witnesses or anyone else in the room.
• Do not call out a person’s number or do anything that might indicate to others that you have identified someone.
• If you want to have a certain person say or do something, make your request to the officer conducting the lineup. All people in the line will then be asked to say or do the same thing.
• Our investigation in this case will continue regardless of whether you identify or do not identify anyone. (CCFAJ recommendation)
SHOWUPS
• Do not assume that the person you will be seeing is the perpetrator merely because we are asking you to look at him [or because he is handcuffed] [or because he is sitting in a patrol car].
• Do not speak with the other witnesses who will be going with us.
• When we arrive, do not say anything in the presence of other witnesses that would indicate you did or did not recognize someone. You will be questioned separately.
• Our investigation in this case will continue regardless of whether you identify or do not identify anyone. (CCFAJ recommendation)
Post-lineup communications
After a live or photo lineup, officers will ordinarily want to talk to the witness about his identification of the suspect or his failure to make an identification. As we will now discuss, such communications are ordinarily appropriate and will not affect the admissibility of subsequent identifications.
HOW CONFIDENT? If the witness identified someone, the CCFAJ recommends that officers inquire as to his degree of confidence that he picked the perpetrator; and that his responses be recorded or included in the lineup report. The Seventh Circuit also addressed this issue in United States v. Williams when it said, “Obtaining immediate estimates of confidence also reduced the chance of error. People often profess greater confidence after the fact; their memories realign to their earlier statements, so that trial testimony may reflect more confidence than is warranted.”90
“ANYONE CLOSELY RESEMBLE?” If the witness did not identify anyone, or if he made only a tentative ID, it is not suggestive to ask whether anyone in the lineup closely resembled the perpetrator. In fact, the court in People v. Perkins 91 pointed out that such a question was “a logical one” after the officer’s chief witness failed to identify a suspect. Said the court, “In order to continue the investigation and make certain he was on the right track, [the officer] needed to explore [the witness’s] recollection and description of the robber.”
WITNESS REACTS TO SEEING SOMEONE: If the witness did not make an ID, but said or did something that indicated he recognized someone in the lineup, it is appropriate to question him about this. Said the Court of Appeal, “It is not impermissible or unduly suggestive for a police officer to question witnesses further if the officer believes the witnesses may actually recognize someone in the lineup.”92
WITNESS REQUESTS INFORMATION: Officers at a lineup may provide information about the suspect to a witness if (1) the witness made a positive or tentative identification of a suspect, and (2) the witness requested the information. For example, in People v. Ochoa 93 a rape victim picked the defendant’s photo but added that, to be sure, she would need to see a profile photo; so the officer showed her one. In rejecting the argument that the officer’s act of providing this information rendered the procedure suggestive, the California Supreme Court said, “Due process does not forbid the state to provide useful further information in response to a witness’s request, for the state is not suggesting anything.”
Similarly, in People v. Perkins 94 the victim of a robbery noticed that one of the robbers had a tattoo of a lightning bolt on his neck. During the lineup, the victim recognized Perkins as the robber but said she “could not be sure” until she knew whether he had such a tattoo; the officer then confirmed that he did. On appeal, the court ruled that the officer’s confirmation did not render the lineup unduly suggestive because the victim had recognized Perkins as the robber before she learned about the tattoo, and that the purpose of her question was only to confirm a “key detail.”
“YOU PICKED THE RIGHT ONE: Officers should not inform a witness that he picked the “right” person in a lineup or otherwise confirm that he selected the suspect because it may have a “corrupting effect” on his subsequent identifications.95 This is especially true if the witness made only a tentative ID. For example, in People v. Gordon 96 police arrested Gordon for the robbery-murder of an armored car guard. At a live lineup, a witness told officers that Gordon “looks familiar, but I’m not certain.” Later that day, an officer phoned the witness to inquire about her comment. According to the court, in the course of the conversation the officer essentially told her that she had “picked the right person.” As the result, all subsequent identifications of Gordon by the witness were suppressed.
Even if the witness positively identified the suspect, officers should not inform him that there was additional evidence of his guilt. For example, in People v. Slutts 97 two witnesses to an indecent exposure tentatively identified Slutts, after which an officer told them that Slutts “had committed a prior similar offense” and needed psychiatric help. The court observed that this statement “was made apparently to persuade the girls to hold to their identification of defendant.” And although this did not result in the suppression of the ID (because the ID occurred beforehand), it was a legitimate issue on appeal.
Other relevant circumstances
WERE THE WITNESSES SEPARATED? Whenever two or more witnesses will be viewing a lineup or showup, it would be inherently suggestive if one of them were to hear another witness identify the suspect. As the court explained in People v. Ingle,98 “It has been recognized that permitting one eyewitness to a crime the opportunity to observe another eyewitness make a photo lineup identification before he himself is asked to make his own identification is unnecessarily suggestive and fraught with the potential for irreparable misidentification.” It has also been noted that a witness who identifies a suspect after hearing another witness identify him may subconsciously become unduly confident of his identification due to “mutual reinforcement.”99
For this reason, it has become standard procedure to segregate the witnesses before the viewing occurs, and question them separately.100 For example, in People v. Sequeira 101 the court ruled that one of the circumstances that rendered a lineup “eminently fair” was that the witnesses “were separated, told not to talk with each other, and to designate their identifications by writing the suspect’s number on a card provided them.”
DOUBLE-BLIND LINEUPS: To help prevent suggestiveness, the CCFAJ has recommended that live and photo lineups be “double-blind,” meaning that the officers who conduct the lineup do not know the identity of the suspect. The advantage of this procedure is that the officers cannot possibly say or do anything—whether intentionally or inadvertently— that would have called attention to the suspect.102 (By the way, it is called a double blind lineup because neither the officers nor the witnesses are informed beforehand of the suspect’s identity.)
SEQUENTIAL LINEUPS: When officers are conducting double-blind live or photo lineups, the CCFAJ recommends that they display the suspect and the fillers to the witness one at a time. These are known as “sequential” lineups, as opposed to simultaneous live lineups in which the suspect and the fillers appear on stage at the same time, and simultaneous photo lineups in which the photographs are displayed all at once.
According to some psychologists, witnesses who view simultaneous lineups may tend to compare the people in the lineup with one another instead of comparing each one with their mental picture of the perpetrator. And this tendency, they contend, may result in misidentifications because, if the perpetrator was not in the lineup, the witness may identify the person who most resembles him. To date, only one California court has discussed the subject of sequential lineups, and its conclusion was positive. The case was People v. Brandon and the court said, “The circumstances surrounding the photographs being shown to [the witness] (loose, in a stack and shown one at a time) reflect she was not influenced by any so-called ‘filler’ photographs.” 103
PRE-LINEUP PHOTO DISPLAY: Just before conducting a lineup, officers have sometimes shown surveillance photos of the perpetrator to the witness. Such a procedure is, to put it mildly, “arguably suggestive.”104 Nevertheless, the courts have not strictly prohibited it when there was good reason to believe the ID was reliable; e.g., the witness got a good look at the perpetrator.105 It is also probably because the perpetrator’s ID is not apt to be a significant issue at trial if prosecutors have photographs of him committing the crime. But if ID will be a contested issue, this procedure should be avoided because, even if the identification is ruled admissible, it is apt to have little weight with the jury.106
RECORDING LINEUPS; RETAINING PHOTOS: To prove that live lineups were fair, the CCFAJ recommends that they be recorded. As for photo lineups, it is already standard practice to retain the photos.107
Identification Trustworthiness
As noted, even if a lineup or showup was unduly suggestive, the resulting identification will not be suppressed if it was nevertheless trustworthy. While the courts will consider the totality of circumstances in determining whether an identification was trustworthy,108 the following circumstances are usually key:
OPPORTUNITY TO OBSERVE PERPETRATOR: The courts almost always note the extent to which the witness had an opportunity to see the perpetrator before, during, or after the crime. This is because the danger of misidentification is particularly grave “when the witness’ opportunity for observation was insubstantial, and thus his susceptibility to suggestion the greatest.”109 Of particular importance are the length of time the witness saw the perpetrator, the distance between them, whether the witness’s view of the perpetrator was obstructed, and the lighting conditions. For example, in ruling that witnesses had a good opportunity to see the perpetrator, the courts have noted the following:
• “two to three minutes . . . within two feet . . . natural light”110
• “up to half an hour . . . under adequate artificial light in her house and under a full moon outdoors”111
• “The robbery took place in the afternoon in a well-lighted bank. The robbers wore no masks. Five bank employees had been able to see the robber for periods ranging up to five minutes.”112
• “close range for at least three minutes”113
• a “clear and unobstructed view [for 15-20 minutes] . . . well-lighted conditions”114
• the victim had an “unobstructed view . . . for at least three minutes”115
• “well-lit bedroom for a couple of minutes”116
• “20-to-30 second opportunity . . . with lighting provided by the headlights of both cars and a streetlight”117
• “Her view of his face with the nylon covering (which did not distort his features) from a foot away lasted about a minute and a half.”118
ATTENTION DIRECTED AT PERPETRATOR: A witness’s identification is especially likely to be deemed trustworthy if his attention had been directed at the perpetrator.119 For example, in People v. Gomez 120 the court ruled that a robbery victim’s ID of the defendant was trustworthy because, among other things, she “kept reminding herself to study the face of the robber because she knew she would be called upon later to identify him.” And in People v. Sanders 121 the court noted that a man who survived an attack in which his friend was killed testified that he “focused on his attackers’ faces in order to identify them if he survived the attack.”
Conversely, the trustworthiness of an identification may become an issue if the witness had only a glance at the suspect, or if he was just a casual or passing observer.122
SOMETHING DISTINCTIVE: In some cases, a witness’s attention may be directed to the perpetrator because there was something distinctive or unusual about him.123 For example, in People v. Cunningham 124 the witnesses to a robbery-murder testified that their attention was initially drawn to the perpetrator because of his unusual appearance which included a “burgundy three-piece pinstripe polyester suit and tie,” “thick glasses with dark rims,” “a mustache that connected with a goatee-like beard,” and his “hair in back was shoulder-length in the middle.”
DETAILED DESCRIPTION: The courts often consider whether the witness had initially provided officers with a detailed description of the perpetrator, or whether the description was vague or general. For example, in ruling that a witness’s description appeared to be trustworthy, the courts have noted the following:
• The description included “the assailant’s approximate age, height, weight, complexion, skin texture, build, and voice.” 125
• The description included the perpetrator’s “race, his height, his build, the color and style of his hair, and the high cheekbone facial feature. It also included clothing [he] wore.”126
• The witness “described his age, facial appearance and his wearing apparel in some detail.”127
• The witness described his “clothing, hair, complexion, facial hair, height, weight, and condition of intoxication.”128
ACCURACY OF INITIAL DESCRIPTION: A strong indication of trustworthiness is the accuracy of the witness’s initial description of the perpetrator; i.e., the number of descriptive details that matched.129 For example, in People v. Guillebeau 130 the court explained that one of the reasons a rape victim’s identification of the defendant was reliable was that she was able to help make a composite picture of her assailant “which strongly resembled appellant.” While inaccuracies are also relevant,131 the courts understand that witnesses are often unable to provide detailed descriptions, and that discrepancies are inevitable. Consequently, a somewhat inaccurate description may be offset by other circumstances that tend to show the ID was reliable.132
INCONSISTENCIES: If an identification was otherwise reliable, some inconsistencies in the witness’s description of the perpetrator will go to the weight of the ID, not its admissibility.133
ID BASED ON MULTIPLE FACTORS: For the same reason that the specificity of a witness’s initial description is a sign of trustworthiness, the courts also consider whether the witness’s subsequent identification of the defendant was based on several characteristics or just one.134 For example, although a witness in People v. Flint 135 “had difficulty” identifying a burglar by his facial features, the Court of Appeal ruled the identification was sufficiently trustworthy because it was also based on “his clothing, posture, build, hairstyle, and race.”
WITNESS TRAINED TO PAY ATTENTION: The trustworthiness of an identification may be bolstered by the fact that the witness had been trained to pay special attention to people he thinks he might need to identify later; e.g., bank tellers, police officers.136 As the United States Supreme Court observed in Manson v. Brathwaite, “[A]s a specially trained, assigned, and experienced officer, [the witness] could be expected to pay scrupulous attention to detail, for he knew that subsequently he would have to find and arrest his [drug] vendor. In addition, he knew that his claimed observations would be subject later to close scrutiny and examination at any trial.”137
WITNESS HAD SEEN PERPETRATOR BEFORE: An ID is naturally likely to be more trustworthy if the witness was acquainted with the perpetrator or had seen him before.138 For example, in ruling that a rape victim’s identification of her attacker was reliable, the court in People v. Nash noted that she “had seen appellant around the neighborhood on one or two occasions prior to this event.”139
ACCURACY IN EARLIER LINEUPS: It may be logical to infer that the witness’s identification was accurate if he previously failed to identify anyone in a lineup in which the defendant was not present.140 Thus, in Neil v. Biggers the Supreme Court pointed out that “the victim made no previous identification at any of the showups, lineups, or photographic showups. Her record for reliability was thus a good one.”141 On the other hand, there may be problems if the witness identified a filler, especially if he did not resemble the defendant.142
LEVEL OF CERTAINTY: The courts frequently note whether, and to what extent, the witness had expressed certainty that the person he picked was the perpetrator.143 A lack of certainty will not, however, render an ID untrustworthy. As the Court of Appeal explained in People v. Lewis, “Lack of positiveness in identification does not destroy the value of the identification but goes onto to its weight.”144 (For additional cases that are related to this subject, see “Mere suggestiveness goes to weight” on page 4.)
IMMEDIATE ID: Although it is relevant that the witness immediately identified the defendant,145 it is seldom a significant circumstance because the courts know that witnesses often take their time in making such an important decision. Furthermore, officers often instruct the witnesses to take their time.146
TIME LAPSE BETWEEN CRIME AND LINEUP: Because memories fade, the length of time between the crime and the lineup or showup is relevant.147
INDEPENDENT EVIDENCE OF GUILT: It is logical to infer that a witness’s ID of the defendant was trustworthy if there was additional independent evidence of his guilt; e.g., the defendant confessed to the crime, his fingerprints were found at the crime scene, he was identified by other witnesses.148
Right to Counsel
Under certain circumstances, a suspect has a right to have counsel present for the purpose of observing the manner in which the lineup was conducted. As we will now discuss, there are essentially three legal issues pertaining to this right: (1) When does a suspect have a right to counsel? (2) What is the attorney permitted to do? (3) How can officers obtain a waiver of the right?
When the right attaches
Under the Sixth Amendment, a suspect acquires a right to have counsel present at a lineup or showup if all of the following circumstances exist: (1) the suspect was charged with a crime and had been arraigned on that charge, (2) the lineup or showup pertained to the charged crime, and (3) the suspect appeared in person at the lineup or showup.
ARRAIGNMENT: In 2008, the United States Supreme Court ruled that, for Sixth Amendment purposes, a suspect becomes “charged” with a crime at the point he makes his first court appearance pertaining to that crime. Said the Court, “[A] criminal defendant’s initial appearance before a judicial officer, where he learns the charge against him and his liberty is subject to restriction, marks the start of adversary judicial proceedings that trigger attachment of the Sixth Amendment right to counsel.”149
IN-PERSON IDENTIFICATION: Even if the suspect had been arraigned on the crime under investigation, he does not have a right to have counsel to observe the lineup procedure unless the witness will be viewing him in person or, in the case of a voice-only lineup, listening to him in person. Consequently, a suspect will not have a right to counsel when the witness views his photograph in a photo lineup, views a videotape of a live lineup, or listens to a tape recording of a voice-only lineup.150
The reason the right to counsel does not attach in these situations is that the defendant’s trial attorney will be able to explore the possibility of suggestiveness by looking at the photos or videotape, or listening to the audio tape. Note, however, that a violation of the right to counsel might occur if officers are unable to provide the defense with copies of the photographs or recordings.151
SUPPRESSION OF EVIDENCE: If a court rules that officers conducted a lineup in violation of the defendant’s right to counsel, the prosecution will be prohibited from introducing testimony that the witness had identified the defendant at the lineup.152 The witness will also be prohibited from identifying the defendant at trial unless prosecutors can prove, by clear and convincing evidence, that the in-court identification was independent of the unlawful lineup identification.153
What the attorney is permitted to do
The attorney’s role at a lineup is limited to that of a silent observer, taking note of any suggestiveness in the procedure so that he can later assist trial counsel in challenging the lineup.154 A good explanation of the attorney’s function was provided by Justice Mosk in People v. Williams:
[D]efense counsel has no affirmative right to be active during the course of the lineup. He cannot rearrange the personnel, cross-examine, ask those in the lineup to say anything or to don any particular clothing or to make any specific gestures. Counsel may not insist law enforcement officials hear his objection to procedures employed, nor may he compel them to adjust their lineup to his views of what is appropriate. At most, defense counsel is merely present at the lineup to silently observe and to later recall his observations for purposes of cross-examination . . . 155
RIGHT TO BE PRESENT WHEN ID IS MADE: Because
the attorney serves as an observer of the identification process, he has a right to be present when the witness is asked if anyone in the lineup was the perpetrator.156 This is because any suggestiveness at that point is just as likely to result in misidentification as suggestivess that occurs during the viewing.
For example, in People v. Williams, discussed above, the defendant’s attorney was present when a witness viewed the lineup, but then the officers took the witness into another room “for the purpose of making his identification.” The attorney asked to observe but his request was denied on grounds that it was against departmental policy. On appeal, the California Supreme Court ruled that such a departmental policy violated Williams’ right to counsel because, said the court, “It is not the moment of viewing alone, but rather the whole procedure by which a suspect is identified that counsel must be able to effectively reconstruct at trial.”
PRE- AND POST-LINEUP INTERVIEWS: The suspect’s attorney does not have a right to be present when officers interview a witness before the lineup begins or after it was completed.157 For example, in People v. Perkins 158 the defendant’s attorney left the lineup after the witness failed to identify Perkins as the man who robbed her. A few minutes later, an officer asked the witness if there was anyone in the lineup who resembled the robber. She replied that one of the men was, in fact, the robber—it was Perkins. On appeal, Perkins, contended that the post-ID interview violated his right to counsel, but the court disagreed, saying, “[S]ince the identification process had been completed, Perkins’ counsel had no more right to be present at the interview than he would at any nonconfrontational identification by a victim. No defendant has the right to demand representation by counsel at every interview between the prosecution and its witnesses.”
Similarly, in People v. Mitcham 159 a robbery victim who was viewing a live lineup at Oakland police headquarters placed a question mark on the lineup card next to Mitcham’s number. The robbery investigator did not immediately ask her to explain the question mark because it was “standard practice in his office not to discuss lineup details in the presence of defense counsel.” One week later, he met with the victim and asked her about the question mark, and she said she was “95% sure” that Mitcham was the robber. On appeal, Mitcham contended that the victim’s identification of him should have been suppressed, urging the California Supreme Court to rule that a lineup is not “over” until the post-lineup interview is completed. But the court refused, ruling instead that the lineup was complete when the victim “filled out and signed the identification card, indicating her identification of defendant, qualified by a question mark.”
Waiver of right to counsel
A suspect may waive the right to counsel, even if he has an attorney.160 To obtain a waiver, officers must begin by advising him of the following rights:
1. You have a right to have counsel present at the lineup.
2. You are not required to participate in the lineup without counsel.
3. If you want an attorney but cannot afford one, the court will appoint one for you at no charge.161
Officers must then ask the suspect if, having these rights in mind, he is willing to waive the right to counsel. Furthermore, like any other waiver, the waiver of the right to counsel must be made freely, meaning that officers must not pressure the suspect to waive. Note that because there are significant differences between the right to counsel at a lineup and the Miranda right to counsel during interrogation, a Miranda waiver does not constitute a waiver of counsel’s presence at a lineup.162
Attorney not available or won’t participate
If the suspect requests a certain attorney who cannot attend the lineup or refuses to do so, officers may proceed with the lineup if they obtain “substitute counsel.”163 If the suspect’s attorney appears at the lineup but, for whatever reason, refuses to observe the procedure, officers may proceed with the lineup without him. For example, in People v. Hart the public defender, “[u]pon seeing the composition of the lineup,” objected that it was unfair and immediately “departed.” On appeal, the California Supreme Court rejected the defendant’s argument that the lineup violated his Sixth Amendment right to counsel because, said the court, “the public defender’s refusal to attend the lineup cannot be equated with a denial of defendant’s right to counsel.”164 In such a situation, however, officers should photograph or videotape the lineup so that prosecutors can prove the lineup was not suggestive.
There is one other option when counsel cannot or will not participate in a lineup: Photograph or record the lineup without the witness being present, then show the witness the photos or the recording of the lineup. As noted earlier, such a procedure does not violate the suspect’s right to counsel because a suspect does not have a right to counsel unless the witness is viewing a live lineup.
Other Lineup Issues
REFUSAL TO STAND IN A LINEUP: A suspect does not have a right to refuse to participate in a lineup, refuse to speak during a voice lineup, or refuse to wear clothing for identification purposes.165 And if he refuses, prosecutors may be permitted to disclose it to the jury at trial as evidence of his consciousness of guilt.166
To help ensure the admissibility of this evidence at trial, officers should notify the suspect that his refusal to participate may be used against him in court as evidence that he knew he would be identified as the perpetrator.167 The following is an example of such an admonition:
You do not have a right to refuse to participate in a lineup. But if you refuse, your decision to do so may be used in court as proof that you are, in fact, guilty of the crime for which you have been arrested, and that you knew the witness[es] at the lineup would positively identify you as the perpetrator. Having these consequences in mind, do you still refuse to participate in the lineup?
Note that if the suspect refuses to speak at a lineup, and if he was previously Mirandized, officers must notify him that the Miranda right to remain silent does not give him a right to refuse to participate in a voice test.168
COMPELLING A SUSPECT TO STAND IN LINEUP: If a suspect refuses to participate in a live lineup, officers may seek a court order that would compel him to do so. Such an order may also authorize officers to use reasonable force if, after being served with a copy of the order, he still refuses to comply.169 As the Seventh Circuit observed in In re Maguire, “While it may not enhance the image of justice to force a [suspect] kicking and screaming into a lineup, the choice has been made by the [suspect], not the court.”170
In terms of form and procedure, it appears that such an order would be virtually the same as a search warrant. First, an officer would submit to the judge an affidavit containing the following: (1) the name of arrestee and any identifying number, (2) the name of the jail in which the arrestee is currently being held, (3) the crime for which the arrestee was arrested, and (4) the names of the affiant and his agency. The affidavit must then demonstrate probable cause to believe (1) that the arrestee committed the crime under investigation, (2) that the results of the lineup would be relevant to the issue of his guilt,171 and (3) that the arrestee notified officers that he would not voluntarily appear in a lineup.
A sample court order is shown on the next page. To obtain a copy via email in Microsoft Word format, send a request from a departmental email address to [email protected].
APPEARANCE ORDERS: If the suspect is in custody in another county in California, officers may seek an “Appearance Order” authorizing them to transport the suspect to the county in which the lineup will be held. Such an order may be issued upon an ex parte declaration that establishes “sufficient cause” to believe that the suspect committed the crime under investigation, and that a live lineup was reasonably necessary.172 If the suspect is out of custody, there is currently no procedure for compelling him to appear in a live lineup.173
DEFENDANTS MOTION FOR LINEUP: A defendant may file a motion for a court order requiring that officers place him in a live lineup. But such a motion may be granted only if it establishes the following: (1) the perpetrator’s identity will be a material issue in the case, (2) there is a reasonable likelihood of a mistaken identification which a lineup would tend to alleviate, and (3) the motion was made in a timely manner.174 | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/16%3A_Suspect_Identification/16.1%3A_Lineups_and_Showups.txt |
Argued: February 20, 1990 / Decided: June 4, 1990
Police placed undercover agent Parisi in a jail cellblock with respondent Perkins, who was incarcerated on charges unrelated to the murder that Parisi was investigating. When Parisi asked him if he had ever killed anybody, Perkins made statements implicating himself in the murder. He was then charged with the murder. The trial court granted respondent's motion to suppress his statements on the ground that Parisi had not given him the warnings required by Miranda v. Arizona384 U.S. 436 , before their conversations. The Appellate Court of Illinois affirmed, holding that Miranda prohibits all undercover contacts with incarcerated suspects that are reasonably likely to elicit an incriminating response.
Held:
An undercover law enforcement officer posing as a fellow inmate need not give Miranda warnings to an incarcerated suspect before asking questions that may elicit an incriminating response. The Miranda doctrine must be enforced strictly, but only in situations where the concerns underlying that decision are present. Those concerns are not implicated here, since the essential ingredients of a "police-dominated atmosphere" and compulsion are lacking. It is Miranda's premise that the danger of coercion results from the interaction of custody and official interrogation, whereby the suspect may feel compelled to speak by the fear of reprisal for remaining silent or in the hope of more lenient treatment should he confess. That coercive atmosphere is not present when an incarcerated person speaks freely to someone whom he believes to be a fellow inmate and whom he assumes is not an officer having official power over him. In such circumstances, Miranda does not forbid mere strategic deception by taking advantage of a suspect's misplaced trust. The only difference between this case and Hoffa v. United States, 385 U.S. 293 which upheld the placing of an undercover agent near a suspect in order to gather incriminating information is that Perkins was incarcerated. Detention, however, whether or not for the crime in question, does not warrant a presumption that such use of an undercover agent renders involuntary the incarcerated suspect's resulting confession. Mathis v. United States, 391 U.S. 1which held that an inmate's statements to a known agent were inadmissible because no Miranda warnings were given is distinguishable. Where the suspect does not [496 U.S. 292, 293] know that he is speaking to a government agent, there is no reason to assume the possibility of coercion. Massiah v. United States, 377 U.S. 201, and similar cases which held that the government may not use an undercover agent to circumvent the Sixth Amendment right to counsel once a suspect has been charged are inapplicable, since, here, no murder charges had been filed at the time of the interrogation. Also unavailing is Perkins' argument that a bright-line rule for the application of Miranda is desirable, since law enforcement officers will have little difficulty applying the holding of this case. Pp. 296-300.
176 Ill. App. 3d 443, 531 N. E. 2d 141, reversed and remanded.
KENNEDY, J., delivered the opinion of the Court, in which REHNQUIST, C. J., and WHITE, BLACKMUN, STEVENS, O'CONNOR, and SCALIA, JJ., joined. BRENNAN, J., filed an opinion concurring in the judgment, post, p. 300. MARSHALL, J., filed a dissenting opinion, post, p. 303.
Marcia L. Friedl, Assistant Attorney General of Illinois, argued the cause for petitioner. With her on the briefs were Neil F. Hartigan, Attorney General, Robert J. Ruiz, Solicitor General, and
Terence M. Madsen and Jack Donatelli, Assistant Attorneys General.
Paul J. Larkin, Jr., argued the cause for the United States as amicus curiae urging reversal. With him on the brief were Solicitor General Starr, Assistant Attorney General Dennis, and Deputy Solicitor General Bryson.
Dan W. Evers, by appointment of the Court, 493 U.S. 930, argued the cause for respondent. With him on the brief was Daniel M. Kirwan. *
[ Footnote * ] Briefs of amici curiae urging reversal were filed for Americans for Effective Law Enforcement, Inc., et al. by Gregory U. Evans, Daniel B. Hales, George D. Webster, Jack E. Yelverton, Fred E. Inbau, Wayne W. Schmidt, Bernard J. Farber, and James P. Manak; and for the Lincoln Legal Foundation et al. by Joseph A. Morris, Donald D. Bernardi, Fred L. Foreman, Daniel M. Harrod, and Jack E. Yelverton.
John A. Powell, William B. Rubenstein, and Harvey Grossman filed a brief for the American Civil Liberties Union et al. as amici curiae urging affirmance. [496 U.S. 292, 294]
JUSTICE KENNEDY delivered the opinion of the Court.
An undercover government agent was placed in the cell of respondent Perkins, who was incarcerated on charges unrelated to the subject of the agent's investigation. Respondent made statements that implicated him in the crime that the agent sought to solve. Respondent claims that the statements should be inadmissible because he had not been given Miranda warnings by the agent. We hold that the statements are admissible. Miranda warnings are not required when the suspect is unaware that he is speaking to a law enforcement officer and gives a voluntary statement.
I
In November 1984, Richard Stephenson was murdered in a suburb of East St. Louis, Illinois. The murder remained unsolved until March 1986, when one Donald Charlton told police that he had learned about a homicide from a fellow inmate at the Graham Correctional Facility, where Charlton had been serving a sentence for burglary. The fellow inmate was Lloyd Perkins, who is the respondent here. Charlton told police that, while at Graham, he had befriended respondent, who told him in detail about a murder that respondent had committed in East St. Louis. On hearing Charlton's account, the police recognized details of the Stephenson murder that were not well known, and so they treated Charlton's story as a credible one.
By the time the police heard Charlton's account, respondent had been released from Graham, but police traced him to a jail in Montgomery County, Illinois, where he was being held pending trial on a charge of aggravated battery, unrelated to the Stephenson murder. The police wanted to investigate further respondent's connection to the Stephenson murder, but feared that the use of an eavesdropping device would prove impracticable and unsafe. They decided instead to place an
undercover agent in the cellblock with respondent and Charlton. The plan was for Charlton and undercover [496 U.S. 292, 295] agent John Parisi to pose as escapees from a work release program who had been arrested in the course of a burglary. Parisi and Charlton were instructed to engage respondent in casual conversation and report anything he said about the Stephenson murder.
Parisi, using the alias "Vito Bianco," and Charlton, both clothed in jail garb, were placed in the cellblock with respondent at the Montgomery County jail. The cellblock consisted of 12 separate cells that opened onto a common room. Respondent greeted Charlton who, after a brief conversation with respondent, introduced Parisi by his alias. Parisi told respondent that he "wasn't going to do any more time" and suggested that the three of them escape. Respondent replied that the Montgomery County jail was "rinky-dink" and that they could "break out." The trio met in respondent's cell later that evening, after the other inmates were asleep, to refine their plan. Respondent said that his girlfriend could smuggle in a pistol. Charlton said: "Hey, I'm not a murderer, I'm a burglar. That's your guys' profession." After telling Charlton that he would be responsible for any murder that occurred, Parisi asked respondent if he had ever "done" anybody. Respondent said that he had and proceeded to describe at length the events of the Stephenson murder. Parisi and respondent then engaged in some casual conversation before respondent went to sleep. Parisi did not give respondent Miranda warnings before the conversations.
Respondent was charged with the Stephenson murder. Before trial, he moved to suppress the statements made to Parisi in the jail. The trial court granted the motion to suppress, and the State appealed. The Appellate Court of Illinois affirmed, 176 Ill. App. 3d 443, 531 N. E. 2d 141 (1988), holding that Miranda v. Arizona, 384 U.S. 436 (1966), prohibits all undercover contacts with incarcerated suspects that are reasonably likely to elicit an incriminating response.
We granted certiorari, 493 U.S. 808 (1989), to decide whether an undercover law enforcement officer must give [496 U.S. 292, 296] Miranda warnings to an incarcerated suspect before asking him questions that may elicit an incriminating response. We now reverse.
II
In Miranda v. Arizona, supra, the Court held that the Fifth Amendment privilege against selfincrimination prohibits admitting statements given by a suspect during "custodial interrogation" without a prior warning. Custodial interrogation means "questioning initiated by law enforcement officers after a person has been taken into custody . . . ." Id., at 444. The warning mandated by Miranda was meant to preserve the privilege during "incommunicado interrogation of individuals in a police-dominated atmosphere." Id., at 445. That atmosphere is said to generate "inherently compelling pressures which work to undermine the individual's will to resist and to compel him to speak where he would not otherwise do so freely." Id., at 467. "Fidelity to the doctrine announced in Miranda requires that it be enforced strictly, but only in those types of situations in which the concerns that powered the decision are implicated." Berkemer v. McCarty, 468 U.S. 420, 437 (1984).
Conversations between suspects and undercover agents do not implicate the concerns underlying Miranda. The essential ingredients of a "police-dominated atmosphere" and compulsion are not present when an incarcerated person speaks freely to someone whom he believes to be a fellow inmate. Coercion is determined from the perspective of the suspect. Rhode Island v. Innis, 446
U.S. 291, 301 (1980); Berkemer v. McCarty, supra, at 442. When a suspect considers himself in the company of cellmates and not officers, the coercive atmosphere is lacking. Miranda, 384 U.S., at 449 ("[T]he `principal psychologica l factor contributing to a successful interrogation is privacy being alone with the person under interrogation'"); id., at 445. There is no empirical basis for the assumption that a suspect speaking to those whom he assumes are not officers will feel compelled to speak by the fear [496 U.S. 292, 297] of reprisal for remaining silent or in the hope of more lenient treatment should he confess.
It is the premise of Miranda that the danger of coercion results from the interaction of custody and official interrogation. We reject the argument that Miranda warnings are required whenever a suspect is in custody in a technical sense and converses with someone who happens to be a government agent. Questioning by captors, who appear to control the suspect's fate, may create mutually reinforcing pressures that the Court has assumed will weaken the suspect's will, but where a suspect does not know that he is conversing with a government agent, these pressures do not exist. The state court here mistakenly assumed that because the suspect was in custody, no undercover questioning could take place. When the suspect has no reason to think that the listeners have official power over him, it should not be assumed that his words are motivated by the reaction he expects from his listeners. "[W]hen the agent carries neither badge nor gun and wears not `police blue,' but the same prison gray" as the suspect, there is no "interplay between police interrogation and police custody." Kamisar, Brewer v. Williams, Massiah and Miranda: What is "Interrogation"? When Does it Matter?, 67 Geo. L. J. 1, 67, 63 (1978).
Miranda forbids coercion, not mere strategic deception by taking advantage of a suspect's misplaced trust in one he supposes to be a fellow prisoner. As we recognized in Miranda: "Confessions remain a proper element in law enforcement. Any statement given freely and voluntarily without any compelling influences is, of course, admissible in evidence." 384 U.S., at 478. Ploys to mislead a suspect or lull him into a false sense of security that do not rise to the level of compulsion or coercion to speak are not within Miranda's concerns. Cf. Oregon v. Mathiason, 429 U.S. 492, 495-496 (1977) (per curiam); Moran v. Burbine, 475 U.S. 412 (1986) (where police fail to inform suspect of attorney's efforts to reach him, [496 U.S. 292, 298] neither Miranda nor the Fifth Amendment requires suppression of prearraignment confession after voluntary waiver).
Miranda was not meant to protect suspects from boasting about their criminal activities in front of persons whom they believe to be their cellmates. This case is illustrative. Respondent had no reason to feel that undercover agent Parisi had any legal authority to force him to answer questions or that Parisi could affect respondent's future treatment. Respondent viewed the cellmate-agent as an equal and showed no hint of being intimidated by the atmosphere of the jail. In recounting the details of the Stephenson murder, respondent was motivated solely by the desire to impress his fellow inmates. He spoke at his own peril.
The tactic employed here to elicit a voluntary confession from a suspect does not violate the Self-Incrimination Clause. We held in Hoffa v. United States, 385 U.S. 293 (1966), that placing an undercover agent near a suspect in order to gather incriminating information was permissible under the Fifth Amendment. In Hoffa, while petitioner Hoffa was on trial, he met often with one Partin, who, unbeknownst to Hoffa, was cooperating with law enforcement officials. Partin reported to officials that Hoffa had divulged his attempts to bribe jury members. We approved using Hoffa's statements at his subsequent trial for jury tampering, on the rationale that "no claim ha[d] been or could [have been] made that [Hoffa's] incriminating statements were the product of any sort of coercion, legal or factual." Id., at 304. In addition, we found that the fact that Partin had fooled Hoffa into thinking that Partin was a sympathetic colleague did not affect the voluntariness of the statements. Ibid. Cf. Oregon v. Mathiason, supra, at 495-496 (officer's falsely telling suspect that suspect's fingerprints had been found at crime scene did not render interview "custodial" under Miranda); Frazier v. Cupp, 394 U.S. 731, 739 (1969); Procunier v. Atchley, 400 U.S. 446, 453 -454 (1971). The only difference between this case and Hoffa is that the suspect here was incarcerated, but [496 U.S. 292, 299] detention, whether or not for the crime in question, does not warrant a presumption that the use of an undercover agent to speak with an incarcerated suspect makes any confession thus obtained involuntary.
Our decision in Mathis v. United States, 391 U.S. 1 (1968), is distinguishable. In Mathis, an inmate in a state prison was interviewed by an Internal Revenue Service agent about possible tax violations. No Miranda warning was given before questioning. The Court held that the suspect's incriminating statements were not admissible at his subsequent trial on tax fraud charges. The suspect in Mathis was aware that the agent was a Government official, investigating the possibility of noncompliance with the tax laws. The case before us now is different. Where the suspect does not know that he is speaking to a government agent there is no reason to assume the possibility that the suspect might feel coerced. (The bare fact of custody may not in every instance require a warning even when the suspect is aware that he is speaking to an official, but we do not have occasion to explore that issue here.)
This Court's Sixth Amendment decisions in Massiah v. United States, 377 U.S. 201 (1964), United States v. Henry, 447 U.S. 264 (1980), and Maine v. Moulton, 474 U.S. 159 (1985), also do not avail respondent. We held in those cases that the government may not use an undercover agent to circumvent the Sixth Amendment right to counsel once a suspect has been charged with the crime. After charges have been filed, the Sixth Amendment prevents the government from interfering with the accused's right to counsel. Moulton, supra, at 176. In the instant case no charges had been filed on the subject of the interrogation, and our Sixth Amendment precedents are not applicable.
Respondent can seek no help from his argument that a bright-line rule for the application of Miranda is desirable. Law enforcement officers will have little difficulty putting into practice our holding that undercover agents need not [496 U.S. 292, 300] give Miranda warnings to incarcerated suspects. The use of undercover agents is a recognized law enforcement technique, often employed in the prison context to detect violence against correctional officials or inmates, as well as for the purposes served here. The interests protected by Miranda are not implicated in these cases, and the warnings are not required to safeguard the constitutional rights of inmates who make voluntary statements to undercover agents.
We hold that an undercover law enforcement officer posing as a fellow inmate need not give Miranda warnings to an incarcerated suspect before asking questions that may elicit an incriminating response. The statements at issue in this case were voluntary, and there is no federal obstacle to their admissibility at trial. We now reverse and remand for proceedings not inconsistent with our opinion
JUSTICE BRENNAN, concurring in the judgment.
The Court holds that Miranda v. Arizona, 384 U.S. 436 (1966), does not require suppression of a statement made by an incarcerated suspect to an undercover agent. Although I do not subscribe to the majority's characterization of Miranda in its entirety, I do agree that when a suspect does not know that his questioner is a police agent, such questioning does not amount to "interrogation" in an "inherently coercive" environment so as to require application of Miranda. Since the only issue raised at this stage of the litigation is the applicability of Miranda, * I concur in the judgment of the Court. [496 U.S. 292, 301]
This is not to say that I believe the Constitution condones the method by which the police extracted the confession in this case. To the contrary, the deception and manipulation practiced on respondent raise a substantial claim that the confession was obtained in violation of the Due Process Clause. As we recently stated in Miller v. Fenton, 474 U.S. 104, 109 -110 (1985):
"This Court has long held that certain interrogation techniques, either in isolation or as applied to the unique characteristics of a particular suspect, are so offensive to a civilized system of justice that they must be condemned under the Due Process Clause of the Fourteenth Amendment. . . .
Although these decisions framed the legal inquiry in a variety of different ways, usually through the `convenient shorthand' of asking whether the confession was `involuntary,' Blackburn v. Alabama, 361 U.S. 199, 207 (1960), the Court's analysis has consistently been animated by the view that `ours is an accusatorial and not an inquisitorial system,' Rogers v. Richmond, 365 U.S. 534, 541 (1961), and that, accordingly, tactics for eliciting inculpatory statements must fall within the broad constitutional boundaries imposed by the Fourteenth Amendment's guarantee of fundamental fairness." [496 U.S. 292, 302]
That the right is derived from the Due Process Clause "is significant because it reflects the Court's consistently held view that the admissibility of a confession turns as much on whether the techniques for extracting the statements, as applied to this suspect, are compatible with a system that presumes innocence and assures that a conviction will not be secured by inquisitorial means as on whether the defendant's will was in fact overborne." Id., at 116. See Spano v. New York, 360 U.S. 315, 320 -321 (1959) ("The abhorrence of society to the use of involuntary confessions does not turn alone on their inherent untrustworthiness. It also turns on the deeprooted feeling that the police must obey the law while enforcing the law; that in the end life and liberty can be as much endangered from illegal methods used to convict those thought to be criminals as from the actual criminals themselves"); see also Degraffenreid v. McKellar, 494 U.S.1071, 1072 -1074 (1990) (MARSHALL, J., joined by BRENNAN, J., dissenting from denial of certiorari).
The method used to elicit the confession in this case deserves close scrutiny. The police devised a ruse to lure respondent into incriminating himself when he was in jail on an unrelated charge. A police agent, posing as a fellow inmate and proposing a sham escape plot, tricked respondent into confessing that he had once committed a murder, as a way of proving that he would be willing to do so again should the need arise during the escape. The testimony of the undercover officer and a police informant at the suppression hearing reveal the deliberate manner in which the two elicited incriminating statements from respondent. See App. 43-53 and 66-73. We have recognized that "the mere fact of custody imposes pressures on the accused; confinement may bring into play subtle influences that will make him particularly susceptible to the ploys of undercover Government agents." United states v. Henry, 447 U.S. 264, 274 (1980). As JUSTICE MARSHALL points out, the pressures of custody make a suspect more likely to confide in others and to engage [496 U.S. 292, 303] in "jailhouse bravado." See post, at 307-308. The State is in a unique position to exploit this vulnerability because it has virtually complete control over the suspect's environment. Thus, the State can ensure that a suspect is barraged with questions from an undercover agent until the suspect confesses. Cf. Mincey v. Arizona437 U.S. 385, 399 (1978); Ashcraft v. Tennessee, 322 U.S. 143, 153-155 (1944). The testimony in this case suggests the State did just that.
The deliberate use of deception and manipulation by the police appears to be incompatible "with a system that presumes innocence and assures that a conviction will not be secured by inquisitorial means," Miller, supra, at 116, and raises serious concerns that respondent's will was overborne. It is open to the lower court on remand to determine whether, under the totality of the circumstances, respondent's confession was elicited in a manner that violated the Due Process Clause. That the confession was not elicited through means of physical torture, see Brown v. Mississippi, 297 U.S. 278 (1936) or overt psychological pressure, see Payne v. Arkansas, 356 U.S.560, 566 (1958), does not end the inquiry. "[A]s law enforcement officers become more responsible, and the methods used to extract confessions more sophisticated, [a court's] duty to enforce federal constitutional protections does not cease. It only becomes more difficult because of the more delicate judgments to be made." Spano, supra, at 321.
Footnote *] As the case comes to us, it involves only the question whether Miranda applies to the questioning of an incarcerated suspect by an undercover agent. Nothing in the Court's opinion suggests that, had respondent previously invoked his Fifth Amendment right to counsel or right to silence, his statements would be admissible. If respondent had invoked either right, the inquiry would focus on whether he subsequently waived the particular right. See Edwards v. Arizona, 451 U.S. 477 (1981): Michigan v. Mosley 423 U.S. 96, 104(1975). As the Court made clear in Moran v. Burbine, [496 U.S. 292, 301] 475 U.S. 412, 421(1986), the waiver of Miranda rights "must [be] voluntary in the sense that it [must be] the product of a free and deliberate choice rather than intimidation, coercion or deception." (Emphasis added.) Since respondent was in custody on an unrelated charge when he was questioned, he may be able to challenge the admission of these statements if he previously had invoked his Miranda rights with respect to that charge. See Arizona v. Roberson, 486 U.S. 675(1988); Mosley, supra, at 104. Similarly, if respondent had been formally charged on the unrelated charge and had invoked his Sixth Amendment right to counsel, he may have a Sixth Amendment challenge to the admissibility of these statements. See Michigan v. Jackson, 475 U.S. 625, 629-636 (1986). Cf. Roberson, supra, at 683-685.
JUSTICE MARSHALL, Dissenting.
This Court clearly and simply stated its holding in Miranda v. Arizona, 384 U.S. 436(1966): "[T]he prosecution may not use statements, whether exculpatory or inculpatory, stemming from custodial interrogation of the defendant unless it demonstrates the use of procedural safeguards effective to secure the privilege against self-incrimination." Id., at 444. The conditions that require the police to apprise a defendant of his constitutional rights custodial interrogation conducted by an agent of the police were present in this [496 U.S. 292, 304] case. Because Lloyd Perkins received no Miranda warnings before he was subjected to custodial interrogation, his confession was not admissible.
The Court reaches the contrary conclusion by fashioning an exception to the Miranda rule that applies whenever "an undercover law enforcement officer posing as a fellow inmate . . . ask[s] questions that may elicit an incriminating response" from an incarcerated suspect. Ante, at 300. This exception is inconsistent with the rationale supporting Miranda and allows police officers intentionally to take advantage of suspects unaware of their constitutional rights. I therefore dissent.
The Court does not dispute that the police officer here conducted a custodial interrogation of a criminal suspect. Perkins was incarcerated in county jail during the questioning at issue here; under these circumstances, he was in custody as that term is defined in Miranda. 384 U.S., at 444; Mathis v. United States, 391 U.S. 1, 4-5 (1968) (holding that defendant incarcerated on charges different from the crime about which he is questioned was in custody for purposes of Miranda). The United States argues that Perkins was not in custody for purpose of Miranda because he was familiar with the custodial environment as a result of being in jail for two days and previously spending time in prison. Brief for United States as Amicus Curiae 11. Perkins' familiarity with confinement, however, does not transform his incarceration into some sort of noncustodial arrangement. Cf. Orozco v. Texas, 394 U.S. 324 (1969) (holding that suspect who had been arrested in his home and then questioned in his bedroom was in custody, notwithstanding his familiarity with the surroundings).
While Perkins was confined, an undercover police officer. with the help of a police informant, questioned him about a serious crime. Although the Court does not dispute that Perkins was interrogated, it downplays the nature of the 35-minute questioning by disingenuously referring to it as a [496 U.S. 292, 305] "conversatio[n]." Ante, at 295, 296. The officer's narration of the "conversation" at Perkins' suppression hearing, however, reveals that it clearly was an interrogation.
"[Agent:] You ever do anyone?
"[Perkins:] Yeah, once in East St. Louis, in a rich white neighborhood.
"Informant: I didn't know they had any rich white neighborhoods in East St. Louis. "Perkins: It wasn't in East St. Louis, it was by a race track in Fairview Heights. . . . "[Agent]: You did a guy in Fairview Heights?
"Perkins: Yeah in a rich white section where most of the houses look the same. "[Informant]: If all the houses look the same, how did you know you had the right house?
"Perkins: Me and two guys cased the house for about a week. I knew exactly which house, the second house on the left from the corner.
"[Agent]: How long ago did this happen?
"Perkins: Approximately about two years ago. I got paid \$5,000 for that job. "[Agent]: How did it go down?
"Perkins: I walked up [to] this guy['s] house with a sawed-off under my trench coat. "[Agent]: What type gun[?]
"Perkins: A .12 gauge Remmington [sic] Automatic Model 1100 sawed-off." App. 49-50.
The police officer continued the inquiry, asking a series of questions designed to elicit specific information about the victim, the crime scene, the weapon, Perkins' motive, and his actions during and after the shooting. Id., at 50-52. This interaction was not a "conversation"; Perkins, the officer, and the informant were not equal participants in a free-ranging discussion, with each man offering his views on different topics. Rather, it was an interrogation: Perkins was subjected to express questioning likely to evoke an incriminating response. [496 U.S. 292, 306] Rhode Island v. Innis, 446 U.S. 291, 300-301 (1980).
Because Perkins was interrogated by police while he was in custody, Miranda required that the officer inform him of his rights. In rejecting that conclusion, the Court finds that "conversations" between undercover agents and suspects are devoid of the coercion inherent in station house interrogations conducted by law enforcement officials who openly represent the State. Ante, at 296. Miranda was not, however, concerned solely with police coercion. It dealt with any police tactics that may operate to compel a suspect in custody to make incriminating statements without full awareness of his constitutional rights. See Miranda, supra, at 468 (referring to "inherent pressures of the interrogation atmosphere"); Estelle v. Smith, 451 U.S. 454, 467(1981) ("The purpose of [the Miranda] admonitions is to combat what the Court saw as `inherently compelling pressures' at work on the person and to provide him with an awareness of the Fifth Amendment privilege and the consequences of forgoing it") (quoting Miranda, 384 U.S., at 467). Thus, when a law enforcement agent structures a custodial interrogation so that a suspect feels compelled to reveal incriminating information, he must inform the suspect of his constitutional rights and give him an opportunity to decide whether or not to talk.
The compulsion proscribed by Miranda includes deception by the police. See Miranda, supra, at 453 (indicting police tactics "to induce a confession out of trickery," such as using fictitious witnesses or false accusations); Berkemer v. McCarty, 468 U.S. 420, 433 (1984) ("The purposes of the safeguards prescribed by Miranda are to ensure that the police do not coerce or trick captive suspects into confessing") (emphasis deleted and added). Cf. Moran v. Burbine, 475 U.S. 412, 421 (1986) ("[T]he relinquishment of the right [protected by the Miranda warnings] must have been voluntary in the sense that it was the product of a free and deliberate choice rather than intimidation, coercion, or deception") (emphasis [496 U.S. 292, 307] added). Although the Court did not find trickery by itself sufficient to constitute compulsion in Hoffa v. United States, 385 U.S. 293(1966), the defendant in that case was not in custody. Perkins, however, was interrogated while incarcerated. As the Court has acknowledged in the Sixth Amendment context: "[T]he mere fact of custody imposes pressures on the accused; confinement may bring into play subtle influences that will make him particularly susceptible to the ploys of undercover Government agents." United States v. Henry, 447 U.S. 264, 274 (1980). See also Massiah v. United States, 377 U.S. 201, 206 (1964) (holding, in the context of the Sixth Amendment, that defendant's constitutional privilege against self-incrimination was "more seriously imposed upon . . . because he did not even know that he was under interrogation by a government agent") (citation and internal quotation marks omitted).
Custody works to the State's advantage in obtaining incriminating information. The psychological pressures inherent in confinement increase the suspect's anxiety, making him likely to seek relief by talking with others. Dix, Undercover Investigations and Police Rulemaking, 53 Texas L. Rev. 203, 230 (1975). See also Gibbs, The First Cut is the Deepest: Psychological Breakdown and Survival in the Detention Setting, in The Pains of Imprisonment 97, 107 (R. Johnson & H. Toch eds. 1982); Hagel-Seymour, Environmenta l Sanctuaries for Susceptible Prisoners, in The Pains of Imprisonment, supra, at 267, 279; Chicago Tribune, Apr. 15, 1990, p. D3 (prosecutors have found that prisoners often talk freely with fellow inmates).
The inmate is thus more susceptible to efforts by undercover agents to elicit information from him. Similarly, where the suspect is incarcerated, the constant threat of physical danger peculiar to the prison environment may make him demonstrate his toughness to other inmates by recounting or inventing past violent acts. "Because the suspect's ability to select people with whom he can confide is completely within their control, the police have a[496 U.S. 292, 308] unique opportunity to exploit the suspect's vulnerability. In short, the police can insure that if the pressures of confinement lead the suspect to confide in anyone, it will be a police agent." (Footnote omitted.) White, Police Trickery in Inducing Confessions, 127 U. Pa. L. Rev. 581, 605 (1979). In this case, the police deceptively took advantage of Perkins' psychologica l vulnerability by including him in a sham escape plot, a situation in which he would feel compelled to demonstrate his willingness to shoot a prison guard by revealing his past involvement in a murder. See App. 49 (agent stressed that a killing might be necessary in the escape and then asked Perkins if he had ever murdered someone).
Thus, the pressures unique to custody allow the police to use deceptive interrogation tactics to compel a suspect to make an incriminating statement. The compulsion is not eliminated by the suspect's ignorance of his interrogator's true identity. The Court therefore need not inquire past the bare facts of custody and interrogation to determine whether Miranda warnings are required.
The Court's adoption of an exception to the Miranda doctrine is incompatible with the principle, consistently applied by this Court, that the doctrine should remain simple and clear. See, e. g., Miranda, supra, at 441-442 (noting that one reason certiorari was granted was "to give concrete constitutional guidelines for law enforcement agencies and courts to follow"); McCarty, supra, at 430 (noting that one of "the principal advantages of the [Miranda] doctrine . . . is the clarity of that rule"); Arizona v. Roberson, 486 U.S. 675, 680(1988) (same). See also New York v. Quarles, 467 U.S. 649, 657-658 (1984) (recognizing need for clarity in Miranda doctrine and finding that narrow "public safety" exception would not significantly lessen clarity and would be easy for police to apply). We explained the benefits of a bright-line rule in Fare v. Michael C., 442 U.S. 707 (1979): "Miranda's holding has the virtue of informing police and prosecutors with specificity as to what they may do in conducting custodial [496 U.S. 292, 309] interrogation, and of informing courts under what circumstances statements obtained during such interrogation are not admissible." Id., at 718.
The Court's holding today complicates a previously clear and straightforward doctrine. The Court opines that "[l]aw enforcement officers will have little difficulty putting into practice our holding that undercover agents need not give Miranda warnings to incarcerated suspects." Ante, at 299-300. Perhaps this prediction is true with respect to fact patterns virtually identical to the one before the Court today. But the outer boundaries of the exception created by the Court are by no means clear. Would Miranda be violated, for instance, if an undercover police officer beat a confession out of a suspect, but the suspect thought the officer was another prisoner who wanted the information for his own purposes?
Even if Miranda, as interpreted by the Court, would not permit such obviously compelled confessions, the ramifications of today's opinion are still disturbing. The exception carved out of the Miranda doctrine today may well result in a proliferation of departmental policies to encourage police officers to conduct interrogations of confined suspects through undercover agents, thereby circumventing the need to administer Miranda warnings. Indeed, if Miranda now requires a police officer to issue warnings only in those situations in which the suspect might feel compelled "to speak by the fear of reprisal for remaining silent or in the hope of more lenient treatment should he confess," ante, at 296-297, presumably it allows custodial interrogation by an undercover officer posing as a member of the clergy or a suspect's defense attorney. Although such abhorrent tricks would play on a suspect's need to confide in a trusted adviser, neither would cause the suspect to "think that the listeners have official power over him," ante, at 297. The Court's adoption of the "undercover agent" exception to the Miranda rule thus is necessarily also the adoption of a substantial loophole in our jurisprudence protecting suspects' Fifth Amendment rights.
I dissent. [496 U.S. 292, 310] | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/17%3A_Jailhouse_Undercover_Operations/17.1%3A_United_States_Supreme_Court_ILLINOIS_v._PERKINS_%281990%29_No._88-1972.txt |
By Kimberly A. Crawford, J.D., 12/95 [Special Agent Crawford is a legal instructor at the FBI Academy.]
Over the years, legal scholars have debated the legality and propriety of using cellmate informants. While some scholars find the practice a "mere strategic deception [that takes] advantage of a suspect's misplaced trust in one he supposes to be a fellow prisoner,"1 others view the use of cellmate informants as being "so offensive to a civilized system of justice that [the practice] must be condemned."2 Despite this debate, law enforcement officers agree that the use of cellmate informants is an investigative technique that works very well in many cases.
In the 1990 case of Illinois v. Perkins,3 the U.S. Supreme Court, while not resolving the debate, answered an important question regarding the constitutionality of using cellmate informants. Specifically, the Court held that the use of cellmate informants does not violate the Miranda4 rule. This decision appeared to clear the way for law enforcement to take advantage of this very effective investigative technique.
However, the permissible use of cellmate informants was again questioned when Perkins subsequently argued successfully in State court that the use of the technique violated his previously invoked Miranda right to counsel.5 Because the Supreme Court refused to hear the case a second time,6 the extent to which cellmate informants can be used lawfully against suspects who have earlier invoked a right to counsel remains open to debate in both lower Federal courts and State courts.
This article reviews the decisions in Perkins and examines subsequent cases dealing with the question left unresolved by the Supreme Court. It then provides a guide to the constitutional use of cellmate informants.
FIFTH AMENDMENT SELF-INCRIMINATION CLAUSE
The Miranda Rule
The fifth amendment to the U.S. Constitution provides in part that "no person...shall be compelled in any criminal case to be a witness against himself...."7 Over two decades ago, the Supreme Court in Miranda v. Arizona8 held that custodial interrogation of an individual creates a psychologically compelling atmosphere that works against this fifth amendment protection.9 In other words, the Court in Miranda believed that an individual in custody undergoing police interrogation would feel compelled to respond to police questioning. This compulsion, which is a byproduct of most custodial interrogation, directly conflicts with every individual's fifth amendment protection against self-incrimination.
Accordingly, the Court developed the now-familiar Miranda warnings as a means of reducing the compulsion attendant in custodial interrogation. The Miranda rule requires that these warnings be given, and the rights they embody be waived, prior to the initiation of custodial interrogation. This rule, however, is not absolute.
In Illinois v. Perkins,10 the Supreme Court recognized that there are limitations to the rule announced in Miranda. The defendant in Perkins was imprisoned in a State correctional facility on an assault charge, when a former fellow inmate and an undercover officer were placed in his cellblock in an attempt to gather information about a murder Perkins was believed to have committed. When discussing the possibility of a prison break, the undercover officer responded to Perkins' claim that he could smuggle in a gun by asking Perkins whether he had ever "done" anyone. In reply, Perkins described at length a murder for hire he had committed. The following day, Perkins was charged with murder.
Prior to trial, Perkins moved to suppress the statements made to the undercover officer. Because no Miranda warnings had been given to Perkins prior to his conversation with the undercover officer, the trial court granted Perkins' motion to suppress. The Appellate Court of Illinois, holding that all undercover contacts with prisoners that are likely to elicit incriminating responses violate the rule in Miranda, affirmed the suppression order.11
The U.S. Supreme Court reversed the appellate court's decision and expressly rejected the argument that "Miranda warnings are required whenever a suspect is in custody in a technical sense and converses with someone who happens to be a government agent."12 Rather, the Court concluded that not every custodial interrogation creates the psychologically compelling atmosphere that Miranda was designed to protect against. When the compulsion is lacking, so is the need for Miranda warnings.
The Court in Perkins found the facts at issue to be a clear example of a custodial interrogation that created no compulsion. Pointing out that compulsion is "determined from the perspective of the suspect,"13 the Court noted that Perkins had no reason to believe that the undercover officer had any official power over him, and therefore, he had no reason to feel any compulsion. On the contrary, Perkins bragged about his role in the murder in an effort to impress those whom he believed to be his fellow inmates. Miranda was not designed to protect individuals from themselves. Consequently, the Court held there was no violation of Miranda and remanded the case to the Illinois courts for further proceedings.
On remand, Perkins moved once again to have his statements suppressed. Perkins' new motion was based on an allegation that, when arrested on the assault charge, he was advised of his rights and requested an attorney. Therefore, Perkins argued the statements subsequently made to the undercover officer violated his Miranda right to counsel as delineated in Minnick v. Mississippi.14
The Minnick Rule
When Miranda warnings are given to individuals in custody who then invoke either their rights to silence or counsel, all interrogation must cease immediately.15 Whether, and under what conditions, law enforcement officers subsequently may attempt to re-interrogate those individuals depends on which rights have been invoked.
In Michigan v. Mosley,16 the Supreme Court essentially interpreted the invocation of the right to silence as a request for time so suspects could think clearly about the situation. If that initial request is scrupulously honored, the Court held that attempts to re-interrogate may occur if suspects are afforded the time requested, or if they indicate, by initiating communications, that they have had enough time to think and now wish to talk.
As a result, re-interrogations following an invocation of the right to silence are deemed appropriate if: 1) A reasonable period of time has elapsed;17 or 2) interrogation was initiated by the suspect. In either case, any renewed attempt to interrogate a suspect must be preceded by a waiver of Miranda rights.
An invocation of the right to counsel, on the other hand, necessarily carries with it a different set of procedural safeguards. Obviously, suspects invoking the right to counsel are not simply asking for time to assess the situation; they are, instead, requesting the assistance of an attorney.
In Minnick, the Court concluded that this invocation of the right to counsel is not satisfied by giving the suspect the opportunity to consult with an attorney. Rather, the Court held that any attempt to interrogate a custodial suspect once that individual has invoked the right to counsel is unlawful unless: 1) The suspect's attorney is actually present; or 2) the suspect changes his mind and reinitiates the interrogation.18
Moreover, the protections afforded suspects who invoke their right to counsel remain in effect as long as they remain in custody. These protections are not crime specific 19 because the invocation implies that suspects are not willing to deal with law enforcement on any criminal matter without the benefit of counsel for as long as they remain in custody.20
Claiming a prior invocation of his right to counsel when first arrested on the assault charge, Perkins argued that the undercover officer's question "have your ever 'done' anyone"amounted to re-interrogation in violation of the rule established in Minnick. Agreeing with Perkins, the Illinois courts granted the motion to suppress. When the Supreme Court refused the government's request to hear the case a second time, the question of whether cellmate informants could lawfully be used following an invocation of the right to counsel was relegated, at least temporarily, to the lower courts.
Application of Minnick to Cellmate Informants in Federal Courts Since the Supreme Court decided the first Perkins case, three Federal courts of appeals 21 have addressed the issue raised by Perkins on remand. In direct opposition to the Illinois courts, all three Federal courts concluded that an invocation of the Miranda right to counsel is not a bar to the subsequent use of a cellmate informant. Although unanimous in their decisions, the three Federal courts are not in complete agreement as to the reasons for reaching this conclusion.
Two of the three Federal courts of appeals reached their conclusion by interpreting the Supreme Court's decision in Perkins as excluding the use of cellmate informants from the definition of interrogation for purposes of Miranda.22 The case of United States v. Stubbs 23 is illustrative.
In Stubbs, the defendant was arrested when a customs official found cocaine on Edwards, her traveling companion. Following the arrest, defendant was advised of her Miranda rights and immediately invoked the right to counsel. Edwards, on the other hand, immediately confessed and agreed to assist the government in its case against defendant. While incarcerated together, defendant reportedly told Edwards during a conversation that she would have to "take the rap" for defendant, but that defendant would take care of Edward's children. Edwards later testified regarding this conversation, and defendant was convicted.
On appeal, defendant claimed the use of her friend as a cellmate informant was interrogation in violation of her fifth amendment right to counsel invoked when she received her Miranda warnings. In support of her claim, defendant relied on the Supreme Court's language in Rhode Island v. Innis,24 which defined interrogation as "not only...express questioning, but also...any words or actions on the part of the police...that the police should know are reasonably likely to elicit an incriminating response from the suspect."25 Because law enforcement officers should have known that placing Edwards in her cell was "reasonably likely to elicit an incriminating response," defendant argued that the tactic was re-interrogation in violation of her invoked right to counsel.
The U.S. Court of Appeals for the 11th Circuit, however, noted that any determination of whether law enforcement activity amounts to interrogation must "focus primarily upon the perceptions of the suspect, rather than the intent of the police."26 Reading the Supreme Court's decision in Perkins as a further refinement of the definition of interrogation, the court of appeals concluded that the use of cellmate informants does not amount to interrogation because no compulsion is perceived by the suspect.27
A third Federal court of appeals reached the conclusion that an invocation of the Miranda right to counsel is not a bar to the use of cellmate informants by a more direct approach. In Alexander v. State,28 the Court of Appeals for the Second Circuit, when confronted with defendant's claim that he had invoked his Miranda right to counsel prior to the government's use of a cellmate informant, regarded the claim as irrelevant and made the following statement:
Regardless of whether Alexander properly invoked his right to counsel, there is no support for the concept of a fifth amendment right to counsel which bars conduct not prohibited by Miranda itself. It is the fifth amendment's prohibition against compelled self-incrimination which provides the constitutional underpinning for the prophylactic Miranda rules, including notice of the right to counsel. Absent a police dominated interrogation, the fifth amendment right to counsel does not attach.29
Despite the fact that the Federal courts are not in agreement as to why the invocation of the Miranda right to counsel does not bar the subsequent use of cellmate informants, the logic of their conclusion is sound. Knowing, as a result of Perkins, that the use of a cellmate informant does not violate Miranda, it would be incongruous to hold that the technique violates Minnick, which is merely an interpretation of the rights guaranteed in Miranda.
When considering the use of a cellmate informant, however, law enforcement officers should be mindful that this issue remains unresolved by the Supreme Court and may be deemed unlawful by State courts following the reasoning of the Illinois court in Perkins. Therefore, the use of cellmate informants after an invocation of the right to counsel should be reviewed by a legal advisor or prosecutor to ensure the technique is legal in a particular jurisdiction.
Fifth Amendment--Due Process
In addition to the self-incrimination clause, the fifth amendment to the U.S. Constitution also provides that "no person shall be...deprived of life, liberty, or property, without the due process of law."30 The due process clause has been interpreted by the Supreme Court as requiring that all defendants in criminal prosecutions be treated with fundamental fairness.31
With respect to confessions, the Court has held that to be fair, a confession must be voluntary.32 To coerce a suspect into making an involuntary statement or confession would be unfair, and thus, the use of that statement against the suspect would constitute a violation of due process.
On the other hand, no unfairness or due process violation would result from the use of an uncoerced statement voluntarily made by the suspect. By their very nature, cell-mate informants are not generally considered coercive. The very reason suspects confide in cellmate informants is because suspects feel comfortable with them.
However, it is conceivable that an overzealous cellmate informant may violate a suspect's due process rights by gathering information through the use of threats or abuse.33 To avoid due process problems, law enforcement officers should select cellmate informants carefully and provide those individuals with clear instructions to ensure that nothing is done to coerce the suspect into making an involuntary statement.
Sixth Amendment--Right To Counsel
Another constitutional concern confronting law enforcement officers contemplating the placement of a cellmate informant is whether the use of the informant will violate the suspect's sixth amendment right to counsel. The sixth amendment to the U.S. Constitution guarantees that "[i]n all criminal prosecutions, the accused shall... have the Assistance of Counsel for his defense."34
The Supreme Court has interpreted the sixth amendment as guaranteeing not merely the right to counsel, but more important, the right to the effective assistance of counsel.35 To be effective, an attorney must be permitted to form a relationship with the accused some time prior to trial,36 and the government cannot interfere needlessly with that relationship. Thus, to resolve all sixth amendment concerns, law enforcement officers contemplating the use of a cellmate informant must determine two things: 1) Did the suspect's right to counsel attach? and 2) if so, what can a cellmate informant do without interfering with that right?
Right to Counsel Attaches at Critical Stage
Determining whether a suspect's right to counsel has attached simply requires the law enforcement officer to discover whether the suspect has reached a critical stage in the prosecution. The Supreme Court has defined the critical stage as the filing of formal charges (i.e. an indictment or an information) or the initiation of adversarial judicial proceedings. If no formal charges have been filed against the suspect and no initial appearance before the court has been conducted, no critical stage in the prosecution has been reached, and a cellmate informant can be used without concern for the suspect's sixth amendment right to counsel. If, on the other hand, a critical stage has been reached, the suspect's sixth amendment right to counsel has attached, and extreme caution must be used to ensure that the cellmate informant does not interfere with that right.
Postcritical Stage Uses for Cellmate Informants
Once it is determined that a suspect's sixth amendment rights have attached, the law enforcement officer must realize that there are only two functions a cellmate informant can perform lawfully without interfering with that suspect's right to counsel. These two functions are: 1) Gathering information regarding an unrelated crime,38 or 2) acting as a listening post.
Unrelated Crimes
Even though the suspect's right to counsel has attached, a cellmate informant may gather information about an unrelated crime because the sixth amendment is crime-specific.40 Under the sixth amendment, a suspect only has the right to the assistance of counsel with respect to the crimes formally charged against him.41 If a cellmate informant is used to elicit information from a suspect that pertains to some unrelated, uncharged crime, there is no unlawful interference with the suspect's right to counsel.
Listening Post
If a cellmate informant is placed with the intent of gathering information about a crime that is the subject of formal charges against the suspect, the only role the cellmate informant may play is that of a listening post. The Supreme Court has determined that simply placing an informant in the cell of a suspect who has been formally charged does not, in and of itself, constitute a sixth amendment violation.42 Rather, there must be some deliberate attempt to elicit information regarding those charges from the suspect.43
It is the act of deliberate elicitation that creates the sixth amendment violation. Consequently, a law enforcement officer who places an informant in a cell of a formally charged suspect in an attempt to obtain information relating to those charges should be prepared to demonstrate that there was no deliberate elicitation on the part of the informant.44
Conclusion
Confined suspects often have an overwhelming desire to talk about their criminal activities with those they consider their peers. Law enforcement officers can take advantage of this phenomenon by placing an informant in the prison population. When doing so, however, officers must be ever mindful of the boundaries set by the fifth and sixth amendments. Thoughtful selection, careful planning, and detailed instruction can ensure that an informant operates within those boundaries and conforms to fifth and sixth amendment standards. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/17%3A_Jailhouse_Undercover_Operations/17.2%3A_A_Constitutional_Guide_to_the_Use_Of_Cellmate_Informants_By_Kimberly_A._Crawford_J.D..txt |
The Framers of the Constitution had fresh memories of a government that accused people of crimes they did not commit and then convicted them in unfair trials. Consequently, they went to great lengths to assure that the new government they established would not engage in such practices. Toward that end, the Constitution and the Bill of Rights guarantee a series of important protections for individuals accused of committing crimes in the United States.
Given the high rates of crime in this nation, some have suggested that the rights of the accused be curtailed. There have been, in fact, several efforts at the national level and in the states to enact "victims' rights" laws, to limit the number of appeals that can be brought by convicted criminals and to make the penalties for crime more severe. In terms of balancing liberty and order, these efforts are clearly aimed at promoting more order. The Constitution, however, keeps the balances tipped decidedly in favor of the accused. In this nation's criminal judicial system, the assumption is that mistakes will be made. Instead of erring on the side of punishing the innocent, however, it is a system that is more likely to let a guilty person go unpunished.
Search and Seizure
The rights of those accused of a crime are spelled out in four of the ten constitutional amendments that make up the Bill of Rights (Amendments Four, Five, Six, and Eight). For the most part, these amendments have been held to apply to both the federal and the state governments. The Fourth Amendment says in part that “the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.” Although there are numerous and tricky exceptions to the general rule, ordinarily the police may not break into a person’s house or confiscate his papers or arrest him unless they have a warrant to do so. This means, for instance, that a policeman cannot simply stop you on a street corner and ask to see what is in your pockets (a power the police enjoy in many other countries), nor can your home be raided without probable cause to believe that you have committed a crime. What if the police do search or seize unreasonably?
The courts have devised a remedy for the use at trial of the fruits of an unlawful search or seizure. Evidence that is unconstitutionally seized is excluded from the trial. This is the so-called exclusionary rule, first made applicable in federal cases in 1914 and brought home to the states in 1961. The exclusionary rule is highly controversial, and there are numerous exceptions to it. But it remains generally true that the prosecutor may not use evidence willfully taken by the police in violation of constitutional rights generally, and most often in the violation of Fourth Amendment rights. (The fruits of a coerced confession are also excluded.)
Double Jeopardy
The Fifth Amendment prohibits the government from prosecuting a person twice for the same offense. The amendment says that no person shall be “subject for the same offence to be twice put in jeopardy of life or limb.” If a defendant is acquitted, the government may not appeal. If a defendant is convicted and his conviction is upheld on appeal, he may not thereafter be reprosecuted for the same crime.
Self-Incrimination
The Fifth Amendment is also the source of a person’s right against self-incrimination (no person “shall be compelled in any criminal case to be a witness against himself”). The debate over the limits of this right has given rise to an immense literature. In broadest outline, the right against self-incrimination means that the prosecutor may not call a defendant to the witness stand during trial and may not comment to the jury on the defendant’s failure to take the stand. Moreover, a defendant’s confession must be excluded from evidence if it was not voluntarily made (e.g., if the police beat the person into giving a confession). In Miranda v. Arizona, the Supreme Court ruled that no confession is admissible if the police have not first advised a suspect of his constitutional rights, including the right to have a lawyer present to advise him during the questioning.Miranda v. Arizona, 384 US 436 (1966). These so-called Miranda warnings have prompted scores of follow-up cases that have made this branch of jurisprudence especially complex.
Speedy Trial
The Sixth Amendment tells the government that it must try defendants speedily. How long a delay is too long depends on the circumstances in each case. In 1975, Congress enacted the Speedy Trial Act to give priority to criminal cases in federal courts. It requires all criminal prosecutions to go to trial within seventy-five days (though the law lists many permissible reasons for delay).
Cross-Examination
The Sixth Amendment also says that the defendant shall have the right to confront witnesses against him. No testimony is permitted to be shown to the jury unless the person making it is present and subject to cross-examination by the defendant’s counsel.
Assistance of Counsel
The Sixth Amendment guarantees criminal defendants the right to have the assistance of defense counsel. During the eighteenth century and before, the British courts frequently refused to permit defendants to have lawyers in the courtroom during trial. The right to counsel is much broader in this country, as the result of Supreme Court decisions that require the state to pay for a lawyer for indigent defendants in most criminal cases.
Cruel and Unusual Punishment
Punishment under the common law was frequently horrifying. Death was a common punishment for relatively minor crimes. In many places throughout the world, punishments still persist that seem cruel and unusual, such as the practice of stoning someone to death. The guillotine, famously in use during and after the French Revolution, is no longer used, nor are defendants put in stocks for public display and humiliation. In pre-Revolutionary America, an unlucky defendant who found himself convicted could face brutal torture before death.
The Eighth Amendment banned these actions with the words that “cruel and unusual punishments [shall not be] inflicted.” Virtually all such punishments either never were enacted or have been eliminated from the statute books in the United States. Nevertheless, the Eighth Amendment has become a source of controversy, first with the Supreme Court’s ruling in 1976 that the death penalty, as haphazardly applied in the various states, amounted to cruel and unusual punishment. Later Supreme Court opinions have made it easier for states to administer the death penalty. As of 2010, there were 3,300 defendants on death row in the United States. Of course, no corporation is on death row, and no corporation’s charter has ever been revoked by a US state, even though some corporations have repeatedly been indicted and convicted of criminal offenses.
Presumption of Innocence
The most important constitutional right in the US criminal justice system is the presumption of innocence. The Supreme Court has repeatedly cautioned lower courts in the United States that juries must be properly instructed that the defendant is innocent until proven guilty. This is the origin of the “beyond all reasonable doubt” standard of proof and is an instruction given to juries in each criminal case. The Fifth Amendment notes the right of “due process” in federal proceedings, and the Fourteenth Amendment requires that each state provide “due process” to defendants.
KEY TAKEAWAY
The US Constitution provides several important protections for criminal defendants, including a prohibition on the use of evidence that has been obtained by unconstitutional means. This would include evidence seized in violation of the Fourth Amendment and confessions obtained in violation of the Fifth Amendment. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/18%3A_Constitutional_Rights_of_the_Accused/18.1%3A_Constitutional_Rights_of_the_Accused.txt |
PETITIONER RESPONDENT
United States Billy Joe Wade
LOCATION
Residence of Gates
DOCKET NO. DECIDED BY
334 Case pending
LOWER COURT
United States Court of Appeals for the Fifth Circuit
CITATION
388 US 218 (1967)
ARGUED
Feb 16, 1967
DECIDED
Jun 12, 1967
GRANTED
Oct 10, 1966
ADVOCATES
Beatrice Rosenberg for the petitioner
Weldon Holcomb for the respondent
Facts of the case
Billy Joe Wade was arrested and indicted for robbing a federally-insured bank. Without giving notice to Wade’s counsel, an FBI officer set up a lineup for two bank employees including Wade and several other prisoners. The officer had each prisoner put strips of tape on their face and say, “Put the money in the bag,” like the robbers did. The employees identified Wade as the robber. At trial, the employees identified him again. Wade’s counsel moved to strike the identifications because the lineup violated Wade’s Fifth Amendment privilege against self-incrimination and his Sixth Amendment right to counsel. The trial court denied the motion, but the U.S. Court of Appeals for the Fifth Circuit reversed, holding that the lineup without counsel violated the Sixth Amendment.
Question
Does a lineup conducted without notifying a suspect'scounsel require exclusion of an in-court identification of a suspect by a witness be excluded from trial?
Conclusion
5–4 Decision
Majority Opinion by William J. Brennan, Jr.
FOR AGAINST
Douglas
Fortas
Warren
Brennan
Clark
Black
White
Stewart
Harlan
Maybe. In a 5-4 decision, Justice William J. Brennan vacated the lower judgment and remanded to determine whether the employees based their trial identifications solely on the lineup. The Supreme Court affirmed that the lineup did not violate Wade’s privilege against self-incrimination. To decide the Sixth Amendment issue, courts must decide whethercounsel’s presence at a pre-trial confrontation of the accused will preserve the accused’s right to a fair trial. In this case, Wade was entitled to counsel at the lineup. The Court held that the identifications should not be excluded if they were based on observations other than the lineup.
Justice Hugo L. Black dissented in part and concurred in part, expressing that the lineup violated Wade's Fifth and Sixth Amendment rights. Justice Black would affirm the conviction, though, because the prosecution did not use evidence of the lineup at trial. Justice Byron R. White dissented in part and concurred in part, stating that Wade was not entitled to counsel at the lineup. Justice John M. Harlan and Justice Potter Stewart joined in the opinion. Justice Abe Fortas concurred in part and dissented in part, stating that the lineup violated Wade’s privilege against self-incrimination. Chief Justice Earl Warren and Justice William O. Douglas joined in the opinion.
18.3: Kirby v. Illinois
PETITIONER RESPONDENT
Thomas Kirby Illinois
LOCATION
Maxwell Street Police Station
DOCKET NO. DECIDED BY
70-5061 Burger Court
LOWER COURT
State appellate court
CITATION
406 US 682 (1972)
ARGUED
Nov 11, 1971
REARGUED
Mar 19 – 20, 1972
DECIDED
Jun 7, 1972
GRANTED
May 24, 1971
ADVOCATES
Michael P. Seng for petitioner
James B. Zagel for respondent
Jerold S. Solovy for petitioner on reargument
Facts of the case
William Shard reported to the Chicago police that two men stole his wallet. The wallet contained traveler’schecksand his social security card, among other things. The next day, two police officers stopped Thomas Kirby and his friend, Ralph Bean. When asked for identification, Kirby produced Shard’s wallet. The officers arrested Kirby and Bean and brought them to the Maxwell Street Police Station. Once there, the officers learned about Shard’s robbery and sent a car to pick up Shard and bring him to the station. Without an attorney present, police asked Shard if Kirby and Bean were his robbers. Shard instantly gave a positive identification. Kirby and Bean were not indicted until almost 6 weeks later. At trial, Kirby unsuccessfully attempted to suppress Shard’s identification. The jury found Kirby guilty and the Appellate Court of Illinois, First District affirmed.
Question
Does due process require that an accused be advised of his right to counsel before an identification that takes place before the accused has been charged formally?
Conclusion
5–4 Decision
Plurality Opinion by Potter Stewart
FOR AGAINST
Stewart
Powell
Blackmun
Burger
Rehnquist
Douglas
Brennan
Marshall
White
No. Justice Potter Stewart, writing for a four justice plurality, delivered the judgment of the court. The plurality expressed that there is no constitutional right to counsel for an identification that takes place before the accused is indicted or formally charged. For this reason, the Exclusionary Rule does not apply, and the identification can be admitted at trial. Chief Justice Warren E. Burger concurred, emphasizing that the right to counsel does not attach until an accused is formally charged. Justice Lewis F. Powell concurred in the judgment, agreeing that the Exclusionary Rule does not apply.
Justice William J. Brennan dissented, arguing that prior Supreme Court Exclusionary Rule precedent just happened to cover post-indictment identifications, but the reasons for using the Rule are the same in preindictment cases. Justice William O. Douglas and Justice Thurgood Marshall joined in the dissent. Justice Byron R. White dissented, arguing that the Exclusionary Rule applies in this case. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/18%3A_Constitutional_Rights_of_the_Accused/18.2%3A_United_States_v._Wade.txt |
Sentencing
In most jurisdictions, the judge holds the responsibility of imposing criminal sentences on convicted offenders. Often, this is a difficult process that defines the application of simple sentencing principles. The latitude that a judge has in imposing sentences can vary widely from state to state. This is because state legislatures often set the minimum and maximum punishments for particular crimes in criminal statutes. The law also specifies alternatives to incarceration that a judge may use to tailor a sentence to an individual offender.
Sentencing Statutes and Guidelines
In the United States, most jurisdictions hold that criminal sentencing is entirely a matter of statute. That is, legislative bodies determine the punishments that are associated with particular crimes. These legislative assemblies establish such sentencing schemes by passing sentencing statutes or establishing sentencing guidelines. These sentences can be of different types that have a profound effect on both the administration of criminal justice and the life of the convicted offender.
Indeterminate Sentences
Indeterminate sentencing is a type of criminal sentencing where the convict is not given a sentence of a certain period in prison. Rather, the amount of time served is based on the offender’s conduct while incarcerated. Most often, a broad range is specified during sentencing, and then a parole board will decide when the offender has earned release.
Determinate Sentences
A determinate sentence is of a fixed length, and is generally not subject to review by a parole board. Convicts must serve all of the time sentenced, minus any good time earned while incarcerated.
Mandatory Sentences
Mandatory sentences are a type of sentence where the absolute minimum sentence is established by a legislative body. This effectively limits judicial discretion in such cases. Mandatory sentences are often included in habitual offender laws, such as repeat drug offenders. Under federal law, prosecutors have the powerful plea bargaining tool of agreeing not to file under the prior felony statute.
Sentencing Guidelines
The Sentencing Reform Act of 1984 was passed in response to congressional concern about fairness in federal sentencing practices. The Act completely changed the way courts sentenced federal offenders. The Act created a new federal agency, the U.S. Sentencing Commission, to set sentencing guidelines for every federal offense. When federal sentencing guidelines went into effect in 1987, they significantly altered judges’ sentencing discretion, probation officers’ preparation of the presentence investigation report, and officers’ overall role in the sentencing process. The new sentencing scheme also placed officers in a more adversarial environment in the courtroom, where attorneys might dispute facts, question guideline calculations, and object to the information in the presentence report. In addition to providing for a new sentencing process, the Act also replaced parole with “supervised release,” a term of community supervision to be served by prisoners after they completed prison terms (Courts, 2015).
When the Federal Courts began using sentencing guidelines, about half of the states adopted the practice. Sentencing guidelines indicate to the sentencing judge a narrow range of expected punishments for specific offenses. The purpose of these guidelines is to limit judicial discretion in sentencing. Several sentencing guidelines use a grid system, where the severity of the offense runs down one axis, and the criminal history of the offender runs across the other. The more serious the offense, the longer the sentence the offender receives. The longer the criminal history of the offender, the longer the sentence imposed. Some systems allow judges to go outside of the guidelines when aggravating or mitigating circumstances exist.
Presentence Investigation
Many jurisdictions require that a presentence investigation take place before a sentence is handed down. Most of the time, the presentence investigation is conducted by a probation officer, and results in a presentence investigation report. This document describes the convict’s education, employment record, criminal history, present offense, prospects for rehabilitation, and any personal issues, such as addiction, that may impact the court’s decision. The report usually contains a recommendation as to the sentence that the court should impose. These reports are a major influence on the judge’s final decision.
Victim Impact Statements
Many states now consider the impact that a crime had on the victim when determining an appropriate sentence. A few states even allow the victims to appear in court and testify. Victim impact statements are usually read aloud in open court during the sentencing phase of a trial. Criminal defendants have challenged the constitutionality of this process on the grounds that it violates the Proportionality Doctrine requirement of the Eighth Amendment, but the Supreme Court has rejected this argument and found the admission of victim statements constitutional.
The Sentencing Hearing
Many jurisdictions pass final sentences in a phase of the trial process known as a sentencing hearing. The prosecutor will recommend a sentence in the name of the people, or defend the recommended sentence in the presentence investigation report, depending on the jurisdiction. Defendants retain the right to counsel during this phase of the process. Defendants also have the right to make a statement to the judge before the sentence is handed down.
Influences on Sentencing Decisions
The severity of a sentence usually hinges on two major factors. The first is the seriousness of the offense. The other, which is much more complex, is the presence of aggravating or mitigating circumstances. In general the more serious the crime, the harsher the punishment.
Concurrent versus Consecutive Sentences
It is not uncommon for a person to be indicted on multiple offenses. This can be several different offenses, or a repetition of the same offense. In many jurisdictions, the judge has the option to order the sentences to be served concurrently or consecutively. A concurrent sentence means that the sentences are served at the same time. A consecutive sentence means that the defendant serves the sentences one after another. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/19%3A_Sentencing/19.1%3A_General_Guidelines.txt |
A sentence is the punishment ordered by the court for a convicted defendant. Statutes usually prescribe punishments at both the state and federal level. The most important limit on the severity of punishments in the United States is the Eighth Amendment.
The Death Penalty
The death penalty is a sentencing option in thirty-eight states and the federal government. It is usually reserved for those convicted of murders with aggravating circumstances. Because of the severity and irrevocability of the death penalty, its use has heavily circumscribed by statutes and controlled by case law. Included among these safeguards is an automatic review by appellate courts.
Incarceration
The most common punishment after fines in the United States is the deprivation of liberty known as incarceration. Jails are short-term facilities, most often run by counties under the auspices of the sheriff’s department. Jails house those awaiting trial and unable to make bail, and convicted offenders serving short sentences or waiting on a bed in a prison. Prisons are long-term facilities operated by state and federal governments. Most prison inmates are felons serving sentences of longer than one year.
Probation
Probation serves as a middle ground between no punishment and incarceration. Convicts receiving probation are supervised within the community, and must abide by certain rules and restrictions. If they violate the conditions of their probation, they can have their probation revoked and can be sent to prison. Common conditions of probation include obeying all laws, paying fines and restitution as ordered by the court, reporting to a probation officer, not associating with criminals, not using drugs, submitting to searches, and submitting to drug tests.
The heavy use of probation is controversial. When the offense is nonviolent, the offender is not dangerous to the community, and the offender is willing to make restitution, then many agree that probation is a good idea. Due to prison overcrowding, judges have been forced to place more and more offenders on probation rather than sentencing them to prison.
Intensive Supervision Probation (ISP)
Intensive Supervision Probation (ISP) is similar to standard probation, but requires much more contact with probation officers and usually has more rigorous conditions of probation. The primary focus of adult ISP is to provide protection of the public safety through close supervision of the offender. Many juvenile programs, and an increasing number of adult programs, also have a treatment component that is designed to reduce recidivism.
Boot Camps
Convicts, often young men, sentenced to boot camps live in a military style environment complete with barracks and rigorous physical training. These camps usually last from three to six months, depending on the particular program. The core ideas of boot camp programs are to teach wayward youths discipline and accountability. While a popular idea among some reformers, the research shows little to no impact on recidivism.
House Arrest and Electronic Monitoring
The Special Curfew Program was the federal courts’ first use of home confinement. It was part of an experimental program-a cooperative venture of the Bureau of Prisons, the U.S. Parole Commission, and the federal probation system-as an alternative to Bureau of Prisons Community Treatment Center (CTC) residence for eligible inmates. These inmates, instead of CTC placement, received parole dates advanced a maximum of 60 days and were subject to a curfew and minimum weekly contact with a probation officer. Electronic monitoring became part of the home confinement program several years later. In 1988, a pilot program was launched in two districts to evaluate the use of electronic equipment to monitor persons in the curfew program. The program was expanded nationally in 1991 and grew to include offenders on probation and supervised release and defendants on pretrial supervision as those who may be eligible to be placed on home confinement with electronic monitoring (Courts, 2015).
Today, most jurisdictions stipulate that offenders sentenced to house arrest must spend all or most of the day in their own homes. The popularity of house arrest has increased in recent years due to monitoring technology that allows a transmitter to be placed on the convict’s ankle, allowing compliance to be remotely monitored. House arrest is often coupled with other sanctions, such as fines and community service. Some jurisdictions have a work requirement, where the offender on house arrest is allowed to leave home for a specified window of time in order to work.
Fines
Fines are very common for violations and minor misdemeanor offenses. First time offenders found guilty of simple assaults, minor drug possession, traffic violations and so forth are sentenced to fines alone. If these fines are not paid according to the rules set by the court, the offender is jailed. Many critics argue that fines discriminate against the poor. A \$200 traffic fine means very little to a highly paid professional, but can be a serious burden on a college student with only a part-time job. Some jurisdictions use a sliding scale that bases fines on income known as day fines. They are an outgrowth of traditional fining systems, which were seen as disproportionately punishing offenders with modest means while imposing no more than “slaps on the wrist” for affluent offenders.
This system has been very popular in European countries such as Sweden and Germany. Day fines take the financial circumstances of the offender into account. They are calculated using two major factors: The seriousness of the offense and the offender’s daily income. The European nations that use this system have established guidelines that assign points (“fine units”) to different offenses based on the seriousness of the offense. The range of fine units varies greatly by country. For example, in Sweden the range is from 1 to 120 units. In Germany, the range is from 1 to 360 units.
The most common process is for court personnel to determine the daily income of the offender. It is common for family size and certain other expenses to be taken into account.
Restitution
When an offender is sentenced to a fine, the money goes to the state. Restitution requires the offender to pay money to the victim. The idea is to replace the economic losses suffered by the victim because of the crime. Judges may order offenders to compensate victims for medical bills, lost wages, and the value of property that was stolen or destroyed. The major problem with restitution is actually collecting the money on behalf of the victim. Some jurisdictions allow practices such as wage garnishment to ensure the integrity of the process. Restitution can also be made a condition of probation, whereby the offender is imprisoned for a probation violation is the restitution is not paid.
Community Service
As a matter of legal theory, crimes harm the entire community, not just the immediate victim. Advocates see community service as the violator paying the community back for the harm caused. Community service can include a wide variety of tasks such as picking up trash along roadways, cleaning up graffiti, and cleaning up parks. Programs based on community service have been popular, but little is known about the impact of these programs on recidivism rates.
“Scarlet-letter” Punishments
While exact practices vary widely, the idea of scarlet-letter punishments is to shame the offender. Advocates view shaming as a cheap and satisfying alternative to incarceration. Critics argue that criminals are not likely to mend their behavior because of shame. There are legal challenges that of kept this sort of punishment from being widely accepted. Appeals have been made because such punishments violate the Eighth Amendment ban on cruel and unusual punishment. Others have been based on the idea that they violate the First Amendment by compelling defendants to convey a judicially scripted message in the form of forced apologies, warning signs, newspaper ads, and sandwich boards. Still other appeals have been based on the notion that shaming punishments are not specifically authorized by State sentencing guidelines and therefore constitute an abuse of judicial discretion (Litowitz, 1997).
Asset Forfeiture
Many jurisdictions have laws that allow the government to seize property and assets used in criminal enterprises. Such a seizure is known as forfeiture. Automobiles, airplanes, and boats used in illegal drug smuggling are all subject to seizure. The assets are often given over to law enforcement. According to the FBI, “Many criminals are motivated by greed and the acquisition of material goods. Therefore, the ability of the government to forfeit property connected with criminal activity can be an effective law enforcement tool by reducing the incentive for illegal conduct. Asset forfeiture takes the profit out of crime by helping to eliminate the ability of the offender to command resources necessary to continue illegal activities” (FBI, 2015).
Asset forfeiture can be both a criminal and a civil matter. Civil forfeitures are easier on law enforcement because they do not require a criminal conviction. As a civil matter, the standard of proof is much lower than it would be if the forfeiture was a criminal penalty. Commonly, the standard for such a seizure is probable cause. With criminal asset forfeitures, law enforcement cannot take control of the assets until the suspect has been convicted in criminal court.
Appeals
An appeal is a claim that some procedural or legal error was made in the prior handling of the case. An appeal results in one of two outcomes. If the appellate court agrees with the lower court, then the appellate court affirms the lower court’s decision. In such cases the appeals court is said to uphold the decision of the lower court. If the appellate court agrees with the plaintiff that an error occurred, then the appellate court will overturn the conviction. This happens only when the error is determined to be substantial. Trivial or insignificant errors will result in the appellate court affirming the decision of the lower court. Winning an appeal is rarely a “get out of jail free” card for the defendant. Most often, the case is remanded to the lower court for rehearing. The decision to retry the case ultimately rests with the prosecutor. If the decision of the appellate court requires the exclusion of important evidence, the prosecutor may decide that a conviction is not possible. | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/19%3A_Sentencing/19.2%3A_Different_Types_of_Sentences.txt |
The rights of victims is currently legislated at the state level and debated at the federal level. Many states have different legislation protecting victims.
Below is Washington State Legistalture chapter 7.96 RCW on proctections for crime victims, survivors, and witnesses.
Crime Victims, Survivors, And Witnesses
Intent
In recognition of the severe and detrimental impact of crime on victims, survivors of victims, and witnesses of crime and the civic and moral duty of victims, survivors of victims, and witnesses of crimes to fully and voluntarily cooperate with law enforcement and prosecutorial agencies, and in further recognition of the continuing importance of such citizen cooperation to state and local law enforcement efforts and the general effectiveness and well-being of the criminal justice system of this state, the legislature declares its intent, in this chapter, to grant to the victims of crime and the survivors of such victims a significant role in the criminal justice system. The legislature further intends to ensure that all victims and witnesses of crime are treated with dignity, respect, courtesy, and sensitivity; and that the rights extended in this chapter to victims, survivors of victims, and witnesses of crime are honored and protected by law enforcement agencies, prosecutors, and judges in a manner no less vigorous than the protections afforded criminal defendants.
Definitions
Unless the context clearly requires otherwise, the definitions in this section apply throughout this chapter.
1. "Crime" means an act punishable as a felony, gross misdemeanor, or misdemeanor under the laws of this state or equivalent federal or local law.
2. "Survivor" or "survivors" of a victim of crime means a spouse or domestic partner, child, parent, legal guardian, sibling, or grandparent. If there is more than one survivor of a victim of crime, one survivor shall be designated by the prosecutor to represent all survivors for purposes of providing the notice to survivors required by this chapter.
3. "Victim" means a person against whom a crime has been committed or the representative of a person against whom a crime has been committed.
4. "Victim impact statement" means a statement submitted to the court by the victim or a survivor, individually or with the assistance of the prosecuting attorney if assistance is requested by the victim or survivor, which may include but is not limited to information assessing the financial, medical, social, and psychological impact of the offense upon the victim or survivors.
5. "Witness" means a person who has been or is expected to be summoned to testify for the prosecution in a criminal action, or who by reason of having relevant information is subject to call or likely to be called as a witness for the prosecution, whether or not an action or proceeding has been commenced.
6. "Crime victim/witness program" means any crime victim and witness program of a county or local law enforcement agency or prosecutor's office, any rape crisis center's sexual assault victim advocacy program as provided in chapter 70.125 RCW, any domestic violence program's legal and community advocate program for domestic violence victims as provided in chapter 70.123 RCW, or any other crime victim advocacy program which provides trained advocates to assist crime victims during the investigation and prosecution of the crime.
Rights of Victims, Survivors, and Witnesses
There shall be a reasonable effort made to ensure that victims, survivors of victims, and witnesses of crimes have the following rights, which apply to any criminal court and/or juvenile court proceeding:
1. With respect to victims of violent or sex crimes, to receive, at the time of reporting the crime to law enforcement officials, a written statement of the rights of crime victims as provided in this chapter. The written statement shall include the name, address, and telephone number of a county or local crime victim/witness program, if such a crime victim/witness program exists in the county;
2. To be informed by local law enforcement agencies or the prosecuting attorney of the final disposition of the case in which the victim, survivor, or witness is involved;
3. To be notified by the party who issued the subpoena that a court proceeding to which they have been subpoenaed will not occur as scheduled, in order to save the person an unnecessary trip to court;
4. To receive protection from harm and threats of harm arising out of cooperation with law enforcement and prosecution efforts, and to be provided with information as to the level of protection available;
5. To be informed of the procedure to be followed to apply for and receive any witness fees to which they are entitled;
6. To be provided, whenever practical, a secure waiting area during court proceedings that does not require them to be in close proximity to defendants and families or friends of defendants;
7. To have any stolen or other personal property expeditiously returned by law enforcement agencies or the superior court when no longer needed as evidence. When feasible, all such property, except weapons, currency, contraband, property subject to evidentiary analysis, and property of which ownership is disputed, shall be photographed and returned to the owner within ten days of being taken;
8. To be provided with appropriate employer intercession services to ensure that employers of victims, survivors of victims, and witnesses of crime will cooperate with the criminal justice process in order to minimize an employee's loss of pay and other benefits resulting from court appearance;
9. To access to immediate medical assistance and not to be detained for an unreasonable length of time by a law enforcement agency before having such assistance administered. However, an employee of the law enforcement agency may, if necessary, accompany the person to a medical facility to question the person about the criminal incident if the questioning does not hinder the administration of medical assistance. Victims of domestic violence, sexual assault, or stalking, as defined in RCW 49.76.020, shall be notified of their right to reasonable leave from employment under chapter 49.76 RCW;
10. With respect to victims of violent and sex crimes, to have a crime victim advocate from a crime victim/witness program, or any other support person of the victim's choosing, present at any prosecutorial or defense interviews with the victim, and at any judicial proceedings related to criminal acts committed against the victim. This subsection applies if practical and if the presence of the crime victim advocate or support person does not cause any unnecessary delay in the investigation or prosecution of the case. The role of the crime victim advocate is to provide emotional support to the crime victim;
11. With respect to victims and survivors of victims, to be physically present in court during trial, or if subpoenaed to testify, to be scheduled as early as practical in the proceedings in order to be physically present during trial after testifying and not to be excluded solely because they have testified;
12. With respect to victims and survivors of victims, to be informed by the prosecuting attorney of the date, time, and place of the trial and of the sentencing hearing for felony convictions upon request by a victim or survivor;
13. To submit a victim impact statement or report to the court, with the assistance of the prosecuting attorney if requested, which shall be included in all presentence reports and permanently included in the files and records accompanying the offender committed to the custody of a state agency or institution;
14. With respect to victims and survivors of victims, to present a statement personally or by representation, at the sentencing hearing for felony convictions; and
15. With respect to victims and survivors of victims, to entry of an order of restitution by the court in all felony cases, even when the offender is sentenced to confinement, unless extraordinary circumstances exist which make restitution inappropriate in the court's judgment.
Right to make statement before postsentence release of offender
1. The legislature recognizes the significant concerns that many victims, survivors of victims, and witnesses of crimes have when offenders are considered for postsentence release from confinement. Therefore, it is the intent of the legislature to ensure that victims, survivors of victims, and witnesses of crimes are afforded the opportunity to make a statement that will be considered prior to the granting of postsentence release from confinement for any offender under the jurisdiction of the indeterminate sentence review board or its successor, or by the governor regarding an application for pardon or commutation of sentence.
2. Victims, survivors of victims, and witnesses of crimes have the following rights:
1. With respect to victims, survivors of victims, and witnesses of crimes, to present a statement to the indeterminate sentence review board or its successor, in person or by representation, via audio or videotape or other electronic means, or in writing, prior to the granting of parole or community custody release for any offender under the board's jurisdiction.
2. With respect to victims and survivors of victims, to present a statement to the clemency and pardons board in person, via audio or videotape or other electronic means, or in writing, at any hearing conducted regarding an application for pardon or commutation of sentence.
Protection of witnesses who testify against criminal gang members
The legislature recognizes that witnesses are often fearful of testifying against criminal gang members. Witnesses may be subject to harassment, intimidation, and threats. While the state does not ensure protection of witnesses, the state intends to provide resources to assist local prosecutors in combating gang-related crimes and to help citizens perform their civic duty to testify in these cases.
Representation of incapacitated or incompetent victim
For purposes of this chapter, a victim who is incapacitated or otherwise incompetent shall be represented by a parent or present legal guardian, or if none exists, by a representative designated by the prosecuting attorney without court appointment or legal guardianship proceedings. Any victim may designate another person as the victim's representative for purposes of the rights enumerated in RCW 7.69.030.
Construction of chapter
Nothing contained in this chapter may be construed to provide grounds for error in favor of a criminal defendant in a criminal proceeding, nor may anything in this chapter be construed to grant a new cause of action or remedy against the state, its political subdivisions, law enforcement agencies, or prosecuting attorneys. The failure of a person to make a reasonable effort to ensure that victims, survivors, and witnesses under this chapter have the rights enumerated in RCW 7.69.030 shall not result in civil liability against that person. This chapter does not limit other civil remedies or defenses of the offender or the victim or survivors of the victim.
At the federal level there have been attempts to legislate a Victims Rights Amendment. There are pros and cons to such an amendment and many legal professionals find themselves on different sides of the debate. Explore opposing sides of the debate below as legal professionals offer their side of the debate.
For
Against | textbooks/workforce/Corrections/Principles_and_Procedures_of_the_Justice_System_(Alvarez)/20%3A_Victims_Rights/20.1%3A_Crime_Victims_Survivors_And_Witnesses.txt |
Module 1: Viewing 3D Models – Part 1
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe AutoCAD’s Ribbon and Toolbar menu systems and set one to used for this book.
2. Describe a wireframe model and explain how it is viewed in 3D.
3. Describe the UCS icon and explain how to configure and display it.
4. Apply the VIEW, 3DORBIT, 3DFORBIT, 3DCORBIT, and UCSICON commands.
AutoCAD’s Menu Systems
AutoCAD has two menu systems that allows you to communicate with it. The two menu systems are Toolbar menu and Ribbon menu. See Figure 1-1. You can, and should, add the Pull-down menu to either the Toolbar or the Ribbon menu. You can use either menu system when completing labs exercises in this book. You can switch between them, if you wish.
WORK ALONG: Setting AutoCAD’s Interface Using Toolbar Menus
If you are using Ribbon menus, skip to WORK ALONG: Setting AutoCAD’s Interface Using Ribbon Menus
Step 1
Launch AutoCAD. AutoCAD’s blank window will display. (Figure Step 1)
Step 2
Click the New icon. This will open the Select Template dialogue box. (Figure Step 2)
Step 3
In the Select template dialogue box, click the template file: 3D Layout English to highlight it. Then click the Open button. This will open AutoCAD’s Graphic window. (Figure Step 3)
Step 4
Click the small arrow in the Workplace Switching icon on the Status bar. Click the workspace: AutoCADbook to set it as the current workspace. Make sure that the check mark is beside the workspace: AutoCADbook as shown in the figure. (Figure Step 4A and 4B)
Step 5
Check to ensure that the tab Model is enabled. It is located on the bottom left corner of the Graphic window. If it is not enabled, click it with the left mouse button. (Figure Step 5)
Step 6
Disable all features on the Status bar by clicking any that display with a blue background as shown in Figure Step 6A. All features should display with a gray background as shown in Figure Step 6B. (Figure Step 6A and 6B)
USER TIP: You can easily check to see if a feature on the Status bar is enabled or disabled by holding your graphic cursor on the icon. A pop up window will display indicating the name of the feature and whether it is currently on or off as shown in the figures below.
Step 7
Move the Graphic cursor onto any toolbar icon and right click the mouse. This will pull down a list of all available toolbar menus. The ones that are preceded with a checkmark are enabled and are currently displayed in the Graphic window. Ensure that the toolbars: Layers, Orbit, Properties, Standard, Styles, UCS, UCS II, View, and Visual Styles are the only ones enabled. Click on the name to toggle the display of the toolbar. (Figure Step 7)
Step 8
Your Graphic screen should match the figure very closely. (Figure Step 8)
Step 9
Enter the MENUBAR command. If is set to 0, set it to 1, as shown below.
Command: MENUBAR
Enter new value for MENUBAR <0>: 1
Command:
Step 10
Click File on the Pull-down menu. Click Exit to close AutoCAD. If you are asked if you want to save the drawing, click No. (Figure Step 10)
Step 11
Skip to Viewing in 3D
WORK ALONG: Setting AutoCAD’s Interface Using Ribbon Menus
If you are using Toolbar menus, go to Viewing in 3D
Step 1
Launch AutoCAD. AutoCAD’s blank window will display. (Figure Step 1)
Step 2
Click the New icon. This will open the Select Template dialogue box. (Figure Step 2)
Step 3
In the Select Template dialogue box, click the template file: 3D Layout English to highlight it. Then click the Open button. This will open AutoCAD’s Graphic window. (Figure Step 3)
Step 4
Click the small arrow in the Workplace Switching icon on the Status bar. Click the workspace: 3D Modeling to set it as the current workspace. Ensure that the check mark is beside the workspace: 3D Modeling as shown in the figure. (Figure Step 4A and 4B)
Step 5
Enter the MENUBAR command and if is set to 0, set it to 1, as shown below. Command: MENUBAR
Enter new value for MENUBAR <0>: 1
Command:
Step 6
Check to ensure that the tab Model is enabled. If it is not enabled, click it with the left mouse button. (Figure Step 6)
Step 7
Disable all features on the Status bar by clicking any that display with a blue background as shown in Figure Step 7A. All features should display with a gray background as shown in Figure Step 7B. (Figure Step 7A and 7B)
Step 8
Click File on the Pull-down menu. Click Exit to close AutoCAD. If you are asked if you want to save the drawing, click No. (Figure Step 8)
USER TIP: You can easily check to see if a feature on the Status bar is enabled or disabled by holding yourgraphic cursor on the icon. A pop up window will display indicating the name of the feature and whether it is currently on or off as shown in the figures on the right.
Viewing in 3D
While working in 2D (two dimensions), the model was always viewed looking down from the top. The only viewing adjustment made, when looking at the model, was the distance (zoom) and the location (pan). There was no need to change the viewing angle. Working in 3D (three dimensions) is quite different. While the model can still be zoomed and panned, you can change the viewing direction and angle of the model.
Throughout the AutoCAD 2D book, the objects being drawn and modified were called the drawing objects even though they were actually model objects on the top view of a model. The reason this was done was to keep it simple and allow you to concentrate on learning to draw and modify geometry. In the AutoCAD 3D book, all objects that are drawn in model space will be referred to as model objects and all objects drawn in paper space will be called drawing objects.
UCS Icon
The User Coordinate System (UCS) icon displays the location and orientation of the current coordinate system. Its location, which is controlled by you, is at either the current coordinate system origin point or in the lower-left corner of the current viewport. When constructing a model, it is best to locate it at the origin point as taught in Modules 3 and 4. Figure 1-2 shows the two different icons as they would appear in a 3D viewing orientation.
A Wireframe Model
A model is the 3 dimensional object drawn at full size and located accurately in relation to model space origin or X0Y0Z0 in the World UCS. A wireframe model is a real-world 3D object represented by lines, circles, arcs, and/or plines located along the edge of the model. See Figure 1-3. A wireframe model is hollow in the centre. That is the reason that lines and arcs on the opposite side of the model can be seen. Think of it as the skeleton of an object. The same model when surfaced or constructed as a solid model will appear as shown in Figure 1-4.
Surfacing a wireframe model and constructing a solid model are covered in Modules 12 to 30.
Wireframe models can be used to view the model from any vantage point, generate standard views in a drawing, generate exploded and perspective views, plus can be used as a skeleton when constructing the surfaced model. A wireframe model cannot be shaded or rendered. A wireframe model can also be used to analyze spatial relationships, including the shortest distance between corners and edges and checking for interferences.
It is important to plan, organize, and construct your model using layers and colors. This will allow you to more easily visualize a complex model and differentiate between objects in various views.
A View
A view is an area displayed by the viewing angle and direction and the location of the target. The current view is the view of the model that is being displayed in the Graphic window. There are many ways of setting the current view of the model and all of them will be covered throughout the AutoCAD 3D book. In this module, using the VIEW command is taught to either select a preset view or set and name user defined views. The basic principles of the orbit commands are also covered.
AutoCAD Command: VIEW
The VIEW command is used to display the preset views or to define, name, and display user defined views of the model.
Shortcut: none
AutoCAD Commands: 3DORBIT, 3DFORBIT, 3DCORBIT
The 3DORBIT, 3DFORBIT, and 3DCORBIT commands allows the user to dynamically orbit the
model changing the viewing angle, viewing direction, and target of the view.
Shortcut: none
AutoCAD Commands: UCSICON
The UCSICON command is used to configure and control the display of the UCS icon.
Shortcut: none
WORK ALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 01-1.
Step 3
In the View pull-down, select Display – UCS Icon – Properties. Ensure that both On and Origin enabled as shown in the figure. This will open the UCS Icon dialogue box. Ensure that the settings are the same in your dialogue box as they are in the figure. (Figure Step 3A and 3B)
Step 4
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0. Explode the block that you just inserted. Your model should appear as shown in the figure. (Figure Step 4)
Step 5
If you are using Toolbar menus, use the View toolbar or if you are using Ribbon menus, use the View section of the Home tab to complete Steps 7 and 8. (Figure Step 5A and 5B)
Step 6
Enter the system variable UCSORTHO, as shown below, and set it to 0.
Command: UCSORTHO
Enter new value for UCSORTHO <1>: 0
Command:
Step 7
Click the Top view icon. Note how the model is now being viewed from the top as shown in the figure. Continue to change the view to display the ten predefined views. Note how the view of the model changes each time you click an icon. (Figure Step 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H, 7I, and 7J)
Step 8
Change the current view to SE Isometric as shown in the figure. (Figure Step 8)
MUST KNOW: The SE Isometric view is the Home view used in the AutoCAD 3D book. It is the view that you can return to anytime you require to a mental view of the model.
Step 9
Enter the 3DFORBIT command using either the toolbar or the pull-down menu. It will display the arcball around the model. Zoom and pan the model to locate it in the centre of the arcball. (Figure Step 9A, 9B, and 9C)
Step 10
Move the cursor onto the small circle on the left side. Press and hold down the left mouse button and while holding it down, move the cursor slowly to the right. until your model appears similar to the figure. You do not have to move it very far. (Figure Step 10)
Step 11
Move the cursor onto the small circle on the bottom. Press and hold down the left mouse button and while holding it down, move the slowly up until your model appears as shown in the figure. (Figure Step 11)
Step 12
Move the cursor inside the arcball. Press and hold down the left mouse button and while holding it down, move it until the model appears as shown in the figure. (Figure Step 12)
Step 13
Press Esc to exit the command. Change the current view to SE Isometric. (Figure Step 13)
Step 14
Using 3DFORBIT, orbit the model to appear similar to the figure. It does not have to match exactly. (Figure Step 14)
Step 15
Enter the VIEW command using either the toolbar or ribbon. This will open the View Manager dialogue box. (Figure Step 15A and 15B)
Step 16
In the Views box, click Model Views to highlight it as shown in the figure and then click the New icon. This will open the New View dialogue box. In the View name box, enter the name: Module 1 View. Click OK to see the view name as shown in the figure. Click OK to close the dialogue box. (Figure Step 16A, 16B, and 16C)
USER TIP: When constructing 3D wireframe models, it is best to view the model in a position that best allows geometry to be inserted and edited. When first beginning to construct 3D models, it is best to start with the SE Isometric view (the Home view) and then slightly orbit it with one of the orbit commands. Do not over-orbit it and lose your mental view of the model. At times, wireframe models can be hard to visualize since they can be visualized inside out. This is a skill that can be learned but in the beginning it is best to keep a mental view of the model.
Step 17
Change the current view to SE Isometric. (Figure Step 17)
Step 18
Save and close the drawing.
MUST KNOW: Be careful when orbiting the model with the arcball. It is very easy to over-orbit and lose your mental view of the model. Orbit it slowly and deliberately keeping a mental view of the model throughout. If you lose the mental view of the model, exit the orbit command and change the view to SE Isometric. Then start the orbit command over again.
Key Principles
Key Principles in Module 1
1. A wireframe model is a real-world 3D object with lines, circles, arcs, and/or plines located along the edge of the A wireframe model is a hollow object.
2. A model is drawn in model space. It is a 3 dimensional object drawn at full size and located accurately in relation to model space origin X0Y0Z0 in the World UCS.
3. A view is simply the way you are looking at the model. It is the model displayed by the viewing angle, viewing direction, and the location of the target.
4. The SE Isometric view is the home view used to keep a mental view of the model.
5. Do not over-orbit the model using the orbit It best to retain a good mental view of the model at all times during model construction. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.01%3A_Module_1-_Viewing_3D_Models__Part_1.txt |
Module 2: Checking the Accuracy of Models
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how the models drawn in lab exercises are checked for accuracy.
Checking the Accuracy of Models
It is extremely important in AutoCAD to draw with 100% accuracy. This cannot be stressed enough as it is essential that each model be positioned and sized perfectly. Models constructed in the lab exercises, in the AutoCAD 3D book, can be checked for accuracy by overlaying it with a key. As a beginner, this helps you know that the models are drawn accurately and shows you any part of the model that is drawn incorrectly. As you become more experienced, you will not require keys to check your models.
WORK ALONG: Checking the Accuracy of Models
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Lab 02-1.
Step 3
Check to ensure that the Model tab is enabled. If it is not, enable it by clicking it with the left mouse button. (Figure Step 3)
Step 4
Ensure that all features on the Status bar are disable by clicking any that are enabled. Your Status bar should match the figure. (Figure Step 4)
Step 5
Ensure that ByLayer is enabled in the first 3 boxes on the Properties menu. (Figure Step 5)
Step 6
Click Format on the Pull-down menu and click Units to open the Drawing Units dialogue box. (Figure Step 6A and 6B)
Step 7
Pull down the Insertion scale list and select Inches. Click OK to close the Drawing Units dialogue box. (Figure Step 7)
Step 8
Click the Insert pull-down and select Block. This will open the Insert dialogue box. (Figure Step 8)
Step 9
Click the small triangle at the end of the Name box. It will pull-down the list of the block names contained in the drawing file. (Figure Step 9)
Step 10
Click the block: AutoCAD 3D Lab 02-1. It will highlight as shown in the figure. The name you select is always the name of the drawing for the lab exercise you are working on. (Figure Step 10)
Step 11
Ensure that the three Specify On-screen boxes are disabled. (Figure Step 11A and 11B)
Step 12
Click the OK button.
Step 13
This will insert a magenta colored overlay key on your model. If there double objects or places where the users model and the magenta model don’t match, the users model is incorrect. If only one model displays, even though it may share the colors magenta and red, the model is accurate. The magenta key resides on layer: Key. If the model is incorrect, turn layer: Key off and correct the model before going on to the next lab exercise or module. After your model is corrected, check it again by turning layer: Key on. (Figure Step 13)
Step 14
Save and close the drawing.
Key Principles
Key Principles in Module 2
1. AutoCAD models must be drawn with 100% accuracy.
2. Most models that you will be drawing in the lab exercises in the AutoCAD 3D book can be checked for accuracy using an overlay key.
3. The name of the key that you select to check your model is always the name of the drawing for the lab exercise for that model.
4. After the key is inserted and only one model displays, the model is 100% accurate. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.02%3A_Module_2-_Checking_the_Accuracy_of_Models.txt |
Module 3: World Coordinate System
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe the World Coordinate System, the UCS icon, and the right-hand rule.
2. Draw 3D models with the UCS located at the World Coordinate System.
The World Coordinate System
AutoCAD has two distinct three-dimensional coordinate systems: the World Coordinate System (WCS) and the User Coordinate System (UCS). The World Coordinate System is permanently located at the absolute coordinates X0Y0Z0. It is a fixed coordinate system which can never be moved. The WCS is normally not used to construct models. You will be using it in this module to construct models as learning tool only.
The User Coordinate System (UCS) is the coordinate system that is used to construct 3D models. The UCS can be placed exactly at the WCS or at any location in 3D space. In this module, model will be constructed with the UCS located at the WCS. It is essential to be able to locate and orientate the UCS to construct most models. This is taught in Module 4 and 5.
The UCS Icon
Figure 3-1 shows the UCS icon and the positive X, Y and Z directions indicated by the UCS icon. When constructing models, it is very important to know which direction is positive and negative on all three axis.
When the UCS is located at the World Coordinate System, it will display a small square at the origin as can be seen in Figure 3-2. If it is located at any other location, it will display as shown in Figure 3-3.
The Right-Hand Rule
Even though the 3D UCS icon indicates the positive Z direction, it is important to know how it is obtained. AutoCAD uses the right-hand rule to find the positive Z direction. See Figure 3-4. To use the right-hand rule, you must first know the positive X and Y directions of the current UCS.
Using your right hand, point your thumb in the direction of the positive X axis. Extend your index finger in the direction of the positive Y axis. The middle finger indicates the direction of the positive Z axis. By rotating your hand, the X, Y and Z axes will rotate to change the UCS location and orientation. It is important to be able to visualize how and where to move the UCS as you construct more complicated models.
Drawing with theZ Coordinate
While drawing in 2D, you only had to worry about entering the X and Y coordinates. Since the Z coordinate was omitted, AutoCAD used the default value of zero. When drawing in 3D, you must add the Z value in some coordinate input. For example, to enter the coordinates X2Y3Z4, enter 2,3,4 if it is an absolute coordinate and @2,3,4 if it is a relative coordinate.
Absolute X0Y0Z0
The absolute coordinate 0,0,0 is the origin of the World Coordinate System. This is the same location used in 2D when only 0,0 was entered. This is an important coordinate location as everything drawn in model space relates back to this location. Keep this in mind when drawing all future models. It is especially important when constructing models that relate to real world locations. For example, when drawing a map, X0Y0Z0 is located at the equator and your model must be drawn in relation to that location.
USER TIP: Similar to working in 2D, it is important to save the objects drawn for construction purposes. In all lab exercises, daw all construction objects on layer Construction and do not delete them when the model is complete. After completing the model, freeze layer Construction. When required, simply thaw layer Construction to display the construction objects.
WORK ALONG: Drawing 3D Wireframe Models with the UCS Located at the WCS
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save the drawing with the name: AutoCAD 3D Workalong 03-1. (Figure Step 2)
Step 3
Set the current view to SE Isometric. (Figure Step 3)
Step 4
Ensure that the UCS Icon is enabled (On) and the Origin is enabled as shown in Module 1 WORKALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands.
Step 5
Set layer: Model as the current layer. Enter the LINE command, as shown below, to draw the lines to start the construction of the model. (Figure Step 5)
Command: LINE
Specify first point: 0,0,0
Specify next point or [Undo]: @2,0
(Since you are working at Z zero, you can omit the Z value.)
Specify next point or [Undo]: @2,2
Specify next point or [Close/Undo]: @4,0
Specify next point or [Close/Undo]: @0,2
Specify next point or [Close/Undo]: @-8,0
Specify next point or [Close/Undo]: C
Command:
(Draw the object that is located on the XY axis as you did in 2D.)
Step 6
Using the OFFSET command, offset the two lines 1.5 units as shown in the figure. Change the layer properties of the two lines to layer: Construction. (Figure Step 6)
Step 7
Use the CIRCLE command to draw a 2 diameter circle with its centre located at the intersection of the two construction lines. (Figure Step 7)
Step 8
Freeze layer: Construction. Enter the COPY command, as shown below, and copy the three lines and the circle 4 units in the positive Z direction. (Figure Step 8).
Command: COPY
Select objects:
(Select the three lines and the circle as shown in Figure Step 8.)
Select objects:
Specify base point or displacement, or [Multiple]: 0,0,0
Specify second point of displacement or <use first point as displacement>: @0,0,4
(Copy the 4 objects 4 units in the positive Z direction. Looking at the UCS or using the right- hand rule will indicated if it is a positive or negative direction.)
Command:
Step 9
Using the 3DFORBIT command, orbit the model slightly. (Figure Step 9)
Step 10
Using the COPY command, copy the 2 lines 2 units in the positive Z directions. (Figure Step 10)
Step 11
Use the LINE command to draw six lines between the ends of the existing lines. Ensure that you snap to the ends of the lines. (Figure Step 11)
Step 12
Using the COPY command, copy the short line located at the right end of the model two times. Ensure that you use snap mode to locate the lines exactly. (Figure Step 12)
Step 13
Draw three lines between the ends of the existing lines. Ensure to snap to the ends of the existing lines. (Figure Step 13)
Step 14
Using the VIEW command, save the current view with the name: Working Isometric. (Figure Step 14)
Step 15
Change the current view to SE Isometric. (Figure Step 15)
Step 16
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Insert the key: AutoCAD 3D Workalong 03-1. It will overlay the model with a magenta model. (Figure Step 16)
Step 17
Save and close the drawing.
WORK ALONG: Drawing 3D Wireframe Models With the UCS Located at the WCS
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout Metric.
Step 2
Save the drawing with the name: AutoCAD 3D Workalong 03-2. (Figure Step 2)
MUST KNOW: AutoCAD has two distinct three-dimensional coordinate systems: the World Coordinate System (WCS) and the User Coordinate System (UCS). The World Coordinate System is located at the absolute coordinates X0Y0Z0. It is a fixed coordinate system and cannot be moved. The WCS is normally not used to construct models. The UCS the coordinate system that is used to construct 3D models. The UCS can be placed exactly at the WCS or at any location in 3D space.
Step 3
Set the current view to SE Isometric. (Figure Step 3)
Step 4
Ensure that the UCS Icon is enabled (On) and the Origin is enabled as shown in Module 1, WORKALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands.
Step 5
Set layer: Model as the current layer. Draw the shape of the top of the object. Use the ARRAY command to speed up the construction. (Figure Step 5)
Step 6
Using the COPY command, as shown below, copy all of the objects 10 units in the negative Z direction. (Figure Step 6)
Command: COPY
Select objects:
(Select all objects.)
Select objects:
Specify base point or displacement, or [Multiple]: 0,0,0
Specify second point of displacement or <use first point as displacement>: @0,0,-10
Command:
Step 7
Using the 3DFORBIT command, orbit the model slightly until it appears similar to the figure. (Figure Step 7)
Step 8
Draw the vertical lines by snapping to the endpoints to complete the wireframe model. (Figure Step 8)
Step 9
Using the VIEW command, save the current view with the name: Working Isometric. (Figure Step 9)
Step 10
Change the view to SE Isometric. (Figure Step 10)
Step 11
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters. Insert the key:
AutoCAD 3D Workalong 03-2. It will overlay the model with a magenta model. (Figure Step 11)
Step 12
Save and close the drawing.
Key Principles
Key Principles in Module 3
1. AutoCAD has two distinct three dimensional coordinate systems: the World Coordinate System (WCS) and the User Coordinate System (UCS).
2. The World Coordinate System is permanently located at the absolute coordinates It is a fixed coordinate system which can never be moved. The WCS is normally not used to construct models.
3. The User Coordinate System is the coordinate system that is normally used to construct 3D The UCS can be placed exactly at the WCS or at any location in 3D space.
4. AutoCAD uses the right-hand rule to find the positive Z To use the right-hand rule, you must first know the positive X and Y directions of the current UCS. Using your right hand, point the thumb in the direction of the positive X axis. Extend your index finger in the direction of the positive Y axis. Your middle finger indicates the direction of the positive Z axis.
5. The absolute coordinate 0,0,0 is the origin of the world coordinate This is the same point used when drawing in 2D when 0,0 was entered. This is an important coordinate location as everything drawn in model space relates back to this location.
Lab Exercise 3-1
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 03-1 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 03-1.
Step 2
Draw all construction objects on layer: Construction and model objects on layer: Model.
Step 3
Draw a wireframe model of the object shown in the figure. (Figure Step 3A and 3B)
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.
Step 5
Save the isometric working view with the name: Working Isometric.
Step 6
When complete, freeze layer: Construction.
Step 7
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 8
Check your drawing with the key. The key name is the same as the drawing name.
Lab Exercise 3-2
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 03-2 3D Layout English Millimeters
Step 1
Save the drawing with the name: AutoCAD 3D Lab 03-2.
Step 2
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 3
Draw a wireframe model of the object shown in the figure. (Figure Step 3A, 3B, 3C, and 3D)
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.
Step 5
Save the isometric working view with the name: Working Isometric.
Step 6
When complete, freeze layer: Construction.
Step 7
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.
Step 8
Check your drawing with the key. The key name is the same as the drawing name. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.03%3A_Module_3-_World_Coordinate_System.txt |
Module 4: User Coordinate System – Part 1
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe the User Coordinate System and the User Construction Plane.
2. Apply the UCSMAN command.
3. Draw 3D models using the User Coordinate System located at the World or at the predefined orthographic UCS locations only.
IMPORTANT – PLEASE READ BEFORE COMPLETING THIS MODULE
AutoCAD 2015 has a bug using the LINE command in 3D. The LINE command works properly when either the World or Top is the current UCS. When any other UCS is the current UCS, the cursor of the LINE command will display the new line in the wrong location. It locates the line in the correct location after you execute the LINE command. It displays correctly when snapping to existing objects and only appears wrong when using coordinates or drawing lines freehand.
A good workaround is to use the PLINE command rather than the LINE command, as it works correctly. After you complete the PLINE command, you can explode the pline to create a line object.
This bug is only in AutoCAD 2015. The LINE command in AutoCAD 2016, 2017 and 2018 works in all UCS locations.
The User Coordinate System
The User Coordinate System (UCS) is the coordinate system used to construct 3D models. It can be located at the WCS or at any location or orientation in 3D space. Being able to locate and orientate the UCS anywhere in 3D space is the secret of 3D modeling.
The User Construction Plane
If you draw an imaginary line from the X axis to the Y axis on the user coordinate system, it forms a imaginary triangular plane as shown in Figure 4-1. When you locate the UCS onto the 3D model, as shown in Figure 4-2, you can see this imaginary triangular plane laying on the surface. Next, picture the plane expanded to fill the whole surface it is located on. See Figure 4-3. This surface is called the User Construction Plane (UCP).
The easiest method of drawing 3D models is to locate and orientate the user construction plane to lie on the surface you currently want to insert or modify object(s) on. Relocate the location of the UCS and continue your model construction until you complete the model. You can use the Z axis to copy the object(s) and draw at a depth parallel to the UCP.
By relocating and orientating the UCS to different locations, you can draw or modify objects on any surface you want. Figure 4-4 shows the user construction plane located on the right side of the model and Figure 4-5 shows it located on the inclined surface.
In this module, all model construction will be drawn in the with the UCS located at the World or in one of the preset orthographic locations only. In Module 5, locating the UCS anywhere in model space will be taught.
AutoCAD Command: UCSMAN
The UCSMAN command is used to locate, orientate, and manage the UCS.
Shortcut: none
WORK ALONG: Moving the UCS to the Preset Locations
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 04-1. Save it in the folder: CAD Courses/AutoCAD 3D/Lab Exercises
Step 3
Set the current UCS to World. Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0. Explode the block.
Step 4
Set the current view to SE Isometric. Your wireframe model should appear as shown in the figure. (Figure Step 4)
Step 5
Enter the UCSMAN command. It will open the UCS dialogue box. Enable the Settings tab and ensure that the settings in the dialogue box matches the figure. (Figure Step 5)
Step 6
Enable the Orthographic UCS’s tab. Select Front and then click the Set Current button. (Figure Step 6)
Step 7
The wireframe model should now appear as shown in the figure. Notice how the XY axis lies on the front plane of the model. (Figure Step 7)
Step 8
Using either the UCS II toolbar or the Home tab ribbon. (Figure Step 8A and 8B)
Step 9
Set the current UCS location to Right and the UCS icon will move onto the right side of the model. Note that the XY plane is now located on the right side plane of the wireframe model. (Figure Step 9A and 9B)
MUST KNOW: To draw in 3D, it is important to visualize a user construction plane located on the X and Y axis. The easiest method of drawing 3D models is to locate and orientate the user construction plane on the surface you are currently modifying. Relocate the location of the UCS and continue model construction until the model is complete.
Step 10
Click the UCS command icon as shown in the figures. With osnap enabled, snap to the end of the line. Note that the UCS icon has now moved to the end of the line that you just selected but it remains located on the right side plane. (Figure Step 10A, 10B, 10C, and 10D)
Step 11
Click Top from the pull-down list. The UCS icon will move onto the top plane of the model. In this case, it locates itself on the WCS. (Figure Step 11)
Step 12
Using the UCS command, move the UCS to corner as shown in the figure. Ensure that you snap to the end of the line. Note how the name of the UCS will display ‘ Unnamed ‘. (Figure Step 12)
Step 13
Click World from the pull-down list. The UCS icon will move onto the WCS. (Figure Step 13)
Step 14
Save and close the drawing.
WORK ALONG: Drawing 3D Wireframe Models Using the UCS
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 04-2. (Figure Step 2A and 2B)
Step 3
Ensure that the current UCS is set to World and the current view is set to SE Isometric.
Step 4
Set layer: Model as the current layer.
Step 5
Using the LINE command, draw the lines to outline the Top view. (Figure Step 5)
Step 6
Copy all of the lines 3 units in the positive Z direction. (Figure Step 6)
Step 7
Using the 3DFORBIT command, orbit the model slightly. (Figure Step 7)
Step 8
Using the LINE command, draw the 6 vertical lines. Ensure that you enable object snap and snap to endpoints of the existing lines. (Figure Step 8)
Step 9
Set the current UCS to Right and then locate the icon by snapping to the corner of the model as shown in the figure. (Figure Step 9)
Step 10
Draw the necessary construction lines using the OFFSET command. Change their layer to layer: Construction. Draw the arc and the circle. (Figure Step 10)
Step 11
Copy the arc and the circle in the negative Z direction. (Figure Step 11)
Step 12
Trim or delete necessary lines. (Figure Step 12)
Step 13
Set the current UCS to Front and then locate it to the corner as shown in the figure. (Figure Step 13)
Step 14
Draw the necessary construction lines using the OFFSET command. Change their layer to layer: Construction. Draw the object lines as shown in the figure. (Figure Step 14)
Step 15
Copy the lines in the negative Z direction and add the necessary object lines. (Figure Step 15)
Step 16
Trim or delete the necessary lines and freeze layer: Construction to complete the wireframe model. (Figure Step 16)
Step 17
Change the current view to SE Isometric. (Figure Step 17)
Step 18
Set the current UCS to World. (Figure Step 18)
Step 19
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Insert the key: AutoCAD 3D Workalong 04-2. It will overlay the model with a magenta wireframe model. (Figure Step 19)
USER TIP: It is best to display the UCS icon at its origin point when you are constructing 3D wireframe models. See the Settings tab in the UCS dialogue box shown below.If the model is zoomed to fill the Graphic window, the UCS icon will appear to be located off the origin point. It actually is not, it simply cannot display where it should. To correct, zoom out to make the model display smaller and the icon will automatically display at the UCS origin.
MUST KNOW: The coordinate location X0Y0Z0 is always referenced to the origin of the UCS. If the UCS is located at the WCS, its origin is the absoluteX0Y0Z0. If the UCS is at any other location, the coordinates location X0Y0Z0 is the relative X0Y0Z0. To work with absolute coordinates, the UCS must be located at the WCS. Use the UCS II toolbar or the UCS dialogue box and change the UCS location to World. When the UCS is at the WCS, the icon will display a small square.
Another way to work with absolute coordinates is to place an asterisk (*) preceding the coordinate value. i.e.
@*4,0,0 specifies a point four units in the X direction of the last point entered relative to the absolute X0Y0Z0 or the WCS.
@4,0,0 specifies a point four units in the X direction of the last point entered relative to the current UCS. *0,0,0 specifies absolute X0Y0Z0 of the WCS regardless of the current location of the UCS.
Key Principles
Key Principles in Module 4
1. The User Coordinate System (UCS) is the coordinate system used to construct 3D It can be located at the WCS or at any location or orientation in 3D space. Being able to locate and orientate the UCS anywhere is the secret of 3D modeling.
2. Another way to work with absolute coordinates is to place an asterisk (*) preceding the coordinate i.e.
@*4,0,0 specifies a point four units in the X direction of the last point entered relative to the absolute X0Y0Z0 or the WCS.
*0,0,0 specifies absolute X0Y0Z0 of the WCS regardless of the current location of the UCS.
Lab Exercise 4-1
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 04-1 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 04-1 as shown above.
Step 2
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 3
Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 4
Draw a wireframe model of the object. (Figure Step 4A and 4B)
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 7
Change the current UCS to World and check the model with the key.
Lab Exercise 4-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 04-2 3D Layout Metric Millimeters
Step 1
Save and name the drawing: AutoCAD 3D Lab 04-2, as shown above.
Step 2
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 3
Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 4
Draw a wireframe model of the object. (Figure Step 4A, 4B, and 4C)
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.
Step 7
Change the current UCS to World and check the model with the key.
Lab Exercise 4-3
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 04-3 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 04-3, as shown above.
Step 2
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 3
Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 4
Draw a wireframe model of the object. (Figure Step 4A, 4B, and 4C)
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 7
Change the current UCS to World and check the model with the key. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.04%3A_Module_4-_User_Coordinate_System__Part_1.txt |
Module 5: User Coordinate System – Part 2
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the UCS command to locate and orientate the UCS to any location necessary for model construction.
2. Draw 3D models using the UCS command to locate and orientate the UCS.
Locating the UCS in 3D Space
In Module 4, the UCSMAN command and the UCS II toolbar or ribbon were used to locate the UCS at preset orthographic locations on the model. In this module, the UCS command and the UCS toolbar or ribbon will be used to move and orientate the UCS to locations that are required to construct more complicated models. The most useful option is locating the UCS by selecting 3 points on the model. While it is still necessary to use the predefined orthographic UCS locations for model construction, not all models can be built using only them.
AutoCAD Command: UCS
The UCS command is used to locate and orientate the UCS on the model or in model space.
Shortcut: none
WORK ALONG: Locating and Orientating the UCS Using the UCS Toolbar
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 05-1.
Step 3
Set the UCS to World. Enter the UNITS command and in the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0.
Step 4
Explode the block you inserted in step 3.
Step 5
Set the current view to SE Isometric. Your model should appear as shown in the figure. (Figure Step 5).
Step 6
Set the UCS location to Right. (Figure Step 6)
Step 7
Click the Origin icon and then snap to the end of the line shown in Figure Step 7A. Your model should now appear as shown in the figure. (Figure Step 7A and 7B)
Step 8
Enable object snap. Click the 3 Point icon. When prompted, select the end of the inclined line. This is the X0Y0Z0 of the UCS. (Figure Step 8)
Step 9
For the second point, select end of the inclined line on the right side of the model. This is the positive X axis. (Figure Step 9)
Step 10
For the third point, select the end of the inclined line on the top. This is the positive Y axis. Your model should now appear as shown in the figure. (Figure Step 10A and 10B)
Step 11
Using what you learned in Steps 8 to 10, locate the UCS as shown in the figure. Ensure that the UCS plane lies on the inclined plane. (Figure Step 11)
Step 12
Using what you learned in Step 8 to 10, locate the UCS as shown in the figure. Ensure that the UCS plane lies on the plane. (Figure Step 12.)
Step 13
Click the World UCS icon. The UCS icon will now be located as shown in the figure. (Figure Step 13)
Step 14
Click the UCS Previous icon and the UCS should now return back to last location. (Figure Step 14)
Step 15
Save and close the drawing.
USER TIP: Before starting to draw any 3D model, it is important for you to pick the best view to start with. The first view you draw is called the Base view. Usually it is the view with the most difficult contour. The more models you draw the easier it will be to select the best Base view.
WORK ALONG: Drawing a 3D Wireframe Model by Locating the UCS
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout Metric.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 05-2. (Figure Step 2A, 2B, and 2C)
Step 3
If you are using toolbar menus, you will be using the UCS, UCS II, and View toolbars. If you are using ribbon menus, enable the Home tab.
Step 4
Ensure that the UCS is located at World. (Figure Step 4)
Step 5
Change the UCS location to Front. (Figure Step 5)
Step 6
Change the current view to Front. The UCS icon should now appear as shown in the figure. (Figure Step 6)
Step 7
Set layer: Model as the current layer. Draw the front contour of the model as shown in the figure. Drawing it in 2D is sometimes easier. It could have been drawn in the 3D view also. (Figure Step 7)
Step 8
Change the current view to SE Isometric. Your model should now appear as shown in the figure. (Figure Step 8)
Step 9
Copy the lines 100 millimeters in the negative Z direction.
Step 10
Orbit the model slight as shown in the figure. Add the lines as shown in the figure. (Figure Step 10)
Step 11
Using the 3 Point method, locate the UCS to the top of the inclined plane. (Figure Step 11)
Step 12
Using OFFSET command, offset the existing lines to locate the centre of the circle and arc on the inclined plane. Change the lines to layer: Construction. Insert the circle and the arc and copy them 25 millimeters to the bottom plane. Before you do complete this step, read the User Tip at the end of this workalong. (Figure Step 12)
Step 13
Trim or delete the lines as required. Using the 3 Point method, locate the UCS to the upper incline plane. (Figure Step 13)
Step 14
Using the OFFSET command, offset the existing lines to locate the centre of the slots on the upper inclined plane. Change the offset lines to layer: Construction. Draw the slots and copy them 25 units to the bottom of the inclined plane. (Figure Step 14)
Step 15
Using the 3 Point method, locate the UCS to the top plane. (Figure Step 15)
Step 16
Construct the square hole, copy it and trim the lines. (Step 16A and 16B)
Step 17
Freeze layer: Construction. Change the current UCS to World and the current view to SE Isometric. (Figure Step 17)
Step 18
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters. Insert the key: AutoCAD 3D Workalong 05-2. It will overlay the model with a magenta model. If it overlays your model perfectly, your model is accurately drawn. (Figure Step 18)
Step 19
Save and close the drawing.
MUST KNOW: The 3 Point icon is the easiest method of changing the UCS to lay on a plane. The order of selecting the 3 points is important. The order is as follows:
1. The X0Y0Z0 or origin of the UCS.
2. The direction of the positive X axis.
3. The direction of the positive Y axis.
Ensure that you enable object snap to snap to existing objects to locate the UCS correctly.
USER TIP: If you have to copy existing geometry in the Z direction, an easy way to do it is to use the COPY command and select the objects first (P1 and P2 – Step 1).
To indicate the copy distance and direction, snap to the ends of an existing line (P3 and P4 in Step 2).
MUST KNOW: The first view of a 3D wireframe model can be drawn in a 2D view. As soon as the objects are copied to make it 3 dimensional, the current view must be changed to a 3D view to complete constructing the model.
Key Principles
Key Principles in Module 5
1. Use the 3 Point method of orientating the UCS as much as possible. It is a very easy to use and will speed your model drawing time. The order of selecting the points is important. Pick 1 – The origin or X0Y0Z0, Pick 2 – The positive X Axis, Pick 3 – The positive Y axis.
2. Before you start drawing any model, you must first decide what is the best view to start drawing first. Usually it is view with the most complex contour. This is called the Base view.
3. The first view of a 3D wireframe model can be drawn in a 2D view. As soon as the objects are copied to make it three dimensional, the view must be changed to a 3D view before continuing the model construction.
Lab Exercise 5-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 05-1 3D Layout English Millimeters
Step 1
Save and name the drawing: AutoCAD 3D Lab 05-1.
Step 2
Draw a wireframe model of the object shown in the figure. (Figure Step 2A ,2B, 2C, 2D, 2E, 2F, and 2G)
Step 3
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.
Step 7
Change the current UCS to World and check the model with the key.
Hint 1
See the steps below to draw the Front view.
Lab Exercise 5-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 05-2 3D Layout Metric Millimeters
Step 1
Save and name the drawing: AutoCAD 3D Lab 05-2.
Step 2
Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, 2D, and 2E)
Step 3
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.
Step 7
Change the current UCS to World and check the model with the key.
Lab Exercise 5-3
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 05-3 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 05-3.
Step 2
Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, 2D, 2E, 2F, and 2G)
Step 3
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 7
Change the current UCS to World and check the model with the key.
Hint 1
To draw the inclined line, see the steps below. (Figure Hint 1)
Step 1
Draw a construction line from corner to corner and a 1 diameter construction circle with the centre at the midpoint of the line.
Step 2
Draw two lines from the endpoints tangent to the circle.
Step 3
Extend the lines and trim the horizontal lines.
Lab Exercise 5-4
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 05-4 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 05-4.
Step 2
Draw a wireframe model of the object. (Figure Step 2A, 2B, 2C, 2D, 2E, and 2F)
Step 3
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 4
Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 5
When complete, freeze layer: Construction.
Step 6
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 7
Change the current UCS to World and check the model with the key.
Hint 1
To draw the arc, you must draw the construction circle and lines to locate its centre. (Figure Hint 1) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.05%3A_Module_5-_User_Coordinate_System__Part_2.txt |
Module 6: Competency Test No. 1 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a one and one-half hour time limit, complete a written exam and a lab exercise without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. Which one of the following coordinate locations would specify a point 2 units in the positive Y direction from the last point entered relative to the current UCS?
1. @*2,0,0
2. @&0,2,0
3. @0,2,0
4. @#0,2,0
5. @0,0,2
2. What are the two distinct 3-dimensional coordinate systems used by AutoCAD?
1. The WCC and UCS.
2. The WCS and UCC.
3. The WSC and USC.
4. The WCS and UCS.
5. The UCS and USC.
3. What two commands can be used to restore a saved UCS location?
1. UCS and VIEW
2. UCSMAN and UCS
3. 3DORBIT and UCSMAN
4. VIEW and USC
5. UCSICON and UCSMAN
4. Which one of the following statements is a false statement when describing the User Coordinate System?
1. It’s current location can be named, saved and restored in the future.
2. It can be located anywhere in 3D space.
3. It defines the User Construction Plane.
4. It is always located at the absolute coordinates X0Y0Z0.
5. It is used to construct 3D models
5. In Figure 6-1, what does the small square indicate? Choose the BEST answer.
1. The location of the last point entered.
2. The UCS is at the centre of the model.
3. The endpoint of the Z axis.
4. The location where X, Y and Z axis meet.
5. The UCS is located at the WCS.
6. Which one of the following coordinate locations would specify a point 3 units in the Z direction from the last point entered relative to the absolute X0Y0Z0 or the WCS?
1. @*0,0,3
2. @-0,0,3
3. @3,0,0
4. @#0,0,3
5. @*3,0,0
7. Which one of the following is a false statement when describing a wireframe model?
1. It is a real-world 3D object represented by lines, circles, arcs and/or plines.
2. It is actually a 2 dimensional object.
3. It does not have any surfacing and is not solid.
4. You can see lines and curves right through it that would not appear in a solid object.
5. If it was a real object, you could put your finger through it.
8. Which one of the following statements is a false statement when describing the World Coordinate System? Choose the BEST answer.
1. It is always located on the top view of the model.
2. It can be located anywhere in 3D space.
3. It is fixed and cannot be moved.
4. It is always located at the absolute coordinates X0Y0Z0.
5. It is not used to construct 3D models.
9. What command is used to define a new UCS location using the 3 Point UCS method?
1. UCS
2. UCSMAN
3. 3DORBIT
4. VIEW
5. UCSICON
10. What direction does the thumb indicate in the right-hand rule?
1. Positive Y
2. Positive Z
3. Negative Y
4. Negative Z
5. Positive X
Lab Exercise 6-1 OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 06-1 3D Layout English Inches
Step 1
Save and name the drawing: AutoCAD 3D Lab 06-1.
Step 2
Draw a wireframe model of the object. (Figure Step 2A, 2B, 2C, 2D, 2E, and 2F)
Step 3
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 4
When complete, freeze layer Construction.
Step 5
Change the view to SE Isometric. (Figure Step 5) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/01%3A_Part_1/1.06%3A_Module_6-_Competency_Test_No._1_Open_Book.txt |
Module 7: Visualizing Multiview Drawings
Learning Outcomes
When you have completed this module, you will be able to:
1. Draw isometric drawings on an isometric grid using multiview drawings as a reference.
2. Construct 3D models in AutoCAD using multiview drawings.
Visualizing 3D Models
In the first six modules, all of the wireframe models that you constructed were referenced to a given 3D view of the model. Since most technical drawings used in the drafting and design world are 2D multiview drawings, 3D models must be able to be drawn using a multiview drawing as a reference to find the model’s shape and dimensions. To construct a 3D model, you must be able to mentally visualize the 3D model using a multiview drawing as a reference.
A good way for you to learn to visualize a 3D model from a 2D multiview drawing is to first draw the model as an isometric drawing. By doing this, it is easier to form a mental image from the multiview drawing. After practicing this for while, you will be able to visualize and construct 3D models without drawing the isometric first.
An isometric drawing is a 2-dimensional drawing that has the XYZ axis drawn at 120 degrees apart as shown in Figure 7-1. In this module, drawing the isometric on an isometric grid will be taught. An isometric grid has the grid lines drawn at 120 degrees as shown in Figure 7-2. Figure 7-3 shows a rectangular box drawn on the isometric grid.
WORK ALONG: Visualizing 3D Models
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 07-1.
Step 3
Set the UCS to World and the view to Top. Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Workalong 07-1 at the coordinates 0,0,0. Explode the block. The drawing should appear as shown in the figure. (Figure Step 3)
Step 4
Change the layer of the isometric grid from layer: 0 to layer: Grid.
Step 5
Lock layer: Grid and set the lineweight of layer: Object to 0.35 mm. (Figure Step 5)
Step 6
Enable OSNAP and LWT. (Figure Step 6)
Step 7
Figure Step 7A shows the multiview drawing of Object 7-1. Set layer: Object as the current layer and draw a box 6 grids long, 5 grids wide and 4 grids high. Where it is drawn is not that important but it should be located somewhere in the top left corner. Ensure that all lines are snapped to the grid intersections. Since layer: Grid is locked, the lines can be freely moved on layer: Object, as required. (Figure Step 7A, 7B, and 7C)
Step 8
To draw the contour of the Front view, count the number of grids for the diagonal cut off. It is 3 grids on the X axis and 2 grids on the Z axis. Using those dimensions, draw the inclined lines on the front and rear view and add the lines to connect them. (Figure Step 8)
Step 9
Trim and delete the lines to complete the contour of the front view. (Figure Step 9)
Step 10
Add the lines to cut out the contour of the Right Side view. (Figure Step 10)
Step 11
Trim and delete the necessary lines to complete the Right Side view contour and then add the lines to form the Top view contour. (Figure Step 11)
Step 12
Trim and delete any unwanted lines to complete the isometric object: Object 7-1. The drawing should appear similar to figure. (Figure Step 12A and 12B)
Step 13
Using what was just taught, draw the isometric drawing of: Object 7-2. Draw it in the top right corner of the grid. (Figure Step 13)
Step 14
The figures show the necessary steps. Try to complete the isometric without looking at the figure. (Figure Step 14A, 14B, 14C, and 14D)
Step 15
Your drawing should now appear similar to the figure. (Figure Step 15)
Step 16
Using what was just taught, draw isometric drawings of the four objects: Object 7-3 to Object 7-6. For the answers, see Figure “Isometric drawing of Object 7-1 to Object 7-6” at the end of this chapter. Try to visualize the 3D model by looking at the multiview drawing and then draw the isometric. Do not look at the answers until you have done your best to complete the isometric drawing of each object. (Figure Step 16)
Step 17
Save and close the drawing.
Key Principles
Key Principles in Module 7
1. An isometric drawing is a 2-dimensional drawing that has the XYZ axis drawn 120 degrees
2. An isometric drawing is only used in the AutoCAD 3D book as a teaching They are mostly obsolete in the CAD design and drafting world.
Lab Exercise 7-1
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 07-1 3D Layout English Inches
Step 1
Draw all construction objects on layer: Construction and all model objects on layer Model. When complete, freeze layer: Construction.
Step 2
Draw a wireframe model of the object. (Figure Step 2A, 2B, and 2C)
Step 3
Start with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.
Step 4
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the current UCS to World and check the model with the key. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/02%3A_Part_2/2.01%3A_Module_7-_Visualizing_Multiview_Drawings.txt |
Module 8: Rotating 3D Models
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the TRIM and EXTEND commands when trimming and extending in three dimensional wireframe modeling.
2. Apply the ROTATE3D command to rotate 3D models.
Rotating in 3D
AutoCAD has individual 2D and 3D rotate commands. The 2D rotate command is ROTATE and in 3D, it is ROTATE3D. In this module, using the ROTATE3D command will be taught. It is used to rotate the model in 3D space. The main difference between the two commands is that the ROTATE command uses a XY point to rotate around and the ROTATE3D command uses two XYZ points or an axis to rotated around. The ROTATE command can be used while 3D modeling as long as all of the objects being rotated are 2D objects and located on the current UCS. If 3D objects are going to be rotated in 3D space, the ROTATE3D command must be used. See Figure 8-1.
AutoCAD Command: ROTATE3D
The ROTATE3D command is used to rotate objects in 3D space around an axis or two XY points.
Shortcut: none
WORK ALONG: Rotating Wireframe Models in 3D Space
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 08-1.
Step 3
On layer: Model, draw a wireframe model of the object shown in the multiview drawing. (Figure Step 3A and 3B)
Step 4
Enter the commands, as shown below, to set the TRIM and EXTEND commands while working in 3D.
Command: TRIM
Current settings: Projection=None, Edge=No Extend
(Note how in this case, the Projection is set to None and Edge to No Extend. Your computer might be different.)
Select cutting edges … (Select an object, any object)
Select objects or <select all>: (Press Enter)
Select object to trim or shift-select to extend or [Fence/Crossing/Project/Edge/eRase/Undo]: P
Enter a projection option [None/Ucs/View] <None>: U
(Enter U for Ucs.)
[Fence/Crossing/Project/Edge/eRase/Undo]: E
Enter an implied edge extension mode [Extend/No extend] <No Extend>: E
(Enter E for Edge and then another for Extend. That means that the intersection of the two objects that you are trimming or extending do not have to physically intersect. AutoCAD will extend them to find the apparent intersection for you.)
Command: EXTEND
Current settings: Projection=Ucs, Edge=Extend
Select cutting edges …
Select objects or <select all>:
(By entering the EXTEND command, you will now see the settings are set for this command as well.)
Command:
Step 5
Enter the TRIM command as shown below. The Current settings: should be set as shown. If not, go back and redo Step 4. If they match, abort the command.
Command: TRIM
Current settings: Projection=UCS, Edge=Extend
Select boundary edges …
Step 6
Enter the ROTATE3D, as shown below, to rotate the model 90 degrees counterclockwise around the X axis. (Figure Step 6)
Command: ROTATE3D
Current positive angle: ANGDIR=counterclockwise ANGBASE=0
Select objects:
Specify opposite corner: 22 found
(Using a window, select all the objects)
Select objects:
Specify first point on axis or define axis by [Object/Last/View/Xaxis/Yaxis/Zaxis/2points]: X
(Rotate around the X axis.)
Specify a point on the X axis <0,0,0>:
(Press Enter to select 0,0,0 as the base point of the rotation.)
Specify rotation angle or [Reference]: 90
(The angle is positive since looking along the X axis towards 0,0,0, counterclockwise is the direction you want to rotate.)
Command:
Step 7
Using what you learned in Step 6, rotate the model 90 degrees around the Y axis. This rotation will have be negative 90 degrees since the rotation is clockwise. (Figure Step 7)
Step 8
Change the UCS to the front and locate it at the centre of the circle. (Figure Step 8)
Step 9
On layer: Construction, draw a line from 0,0,0 at any angle and any length. The line you draw does not have to match the figure exactly. Draw it by eye. (Figure step 9)
Step 10
Change to the Front view to ensure that the line was drawn correctly. (Figure Step 10)
MUST KNOW: The TRIM and EXTEND commands should have the following default settings when working in 3D:
Current settings: Projection=UCS, Edge=Extend
Step 11
Change the current view to SE Isometric and enter the ROTATE3D command, as shown below, to rotate the model using the Reference option. (Figure Step 11)
Command: ROTATE3D
Current positive angle: ANGDIR=counterclockwise ANGBASE=0
Select objects:
(Select all of the model objects in a window. Do not include the reference line that you just drew in the selection.)
Specify opposite corner: 22 found
Select objects:
Specify first point on axis or define axis by
[Object/Last/View/Xaxis/Yaxis/Zaxis/2points]: Z
(Rotating around the Z axis.)
Specify a point on the Z axis <0,0,0>:
Specify rotation angle or [Reference]: R
Specify the reference angle <0>: (cen) P1
Specify second point: (cen) P2
Specify the new angle: (cen) P1
(Note that you have to select the P1 location twice.)
Specify second point: (end) P3
Command:
MUST KNOW: Unlike the ROTATE command where the object is rotated around a point, the ROTATE3D uses two XYZ points to rotated around. You can use the X, Y or Z axis or two endpoints of a line.
Step 12
The wireframe model should now appear as shown in Figure Step 12A. Change the current view to Front to ensure that the model was rotated correctly. (Figure Step 12A and 12B)
Step 13
Save and close the drawing.
USER TIP: When using the ROTATE3D command, ensure that the ANGDIR and ANGBASE system variables are set as shown below. These setting will display when you enter the command, as you can see below. After you become more familiar using 3D, you can change these settings. While working on the AutoCAD 3D book, leave them set as shown.
Command: ROTATE3D
Current positive angle: ANGDIR=counterclockwise ANGBASE=0
Key Principles
Key Principles in Module 8
1. While working in 3D, the TRIM and EXTEND commands should have the following default settings: Projection=UCS, Edge=Extend
2. The ROTATE command, used for a 2D rotate, uses a XY point to rotate For a 3D rotate using the ROTATE3D command, one of the axises, a line or two XYZ points must be specified to rotate around.
3. To find whether the 3D rotation direction is counterclockwise or clockwise, look at 0,0,0 from the positive end of the axis you are rotating around.
Lab Exercise 8-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 08-1 3D Layout English Inches
Step 1
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 2
Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C,and 2D)
Step 3
When complete, freeze layer: Construction.
Step 4
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the location of the UCS to World and check the model with the key.
Step 5
Ensure that the USC is set to World and the current view is SE Isometric. (Figure Step 5)
Step 6
Rotate the model 90 degrees around the X axis. (Figure Step 6)
Step 7
Rotate the model 90 degrees around the Y axis. (Figure Step 7)
Step 8
Rotate the model 90 degrees around the X axis. (Figure Step 8)
Step 9
Rotate the model 90 degrees around the Z axis. (Figure Step 9)
Step 10
Save and close the drawing.
Lab Exercise 8-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 08-2 3D Layout English Inches
Step 1
Draw all construction objects on layer: Construction and all model objects on layer: Model.
Step 2
Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, and 2D)
Step 3
When complete, freeze layer: Construction.
Step 4
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the location of the UCS to World and check the model with the key.
Step 5
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/02%3A_Part_2/2.02%3A_Module_8-_Rotating_3D_Models.txt |
Module 9: Arraying and Mirroring 3D Models
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the 3DARRAY and MIRROR3D commands to construct and modify 3D models.
Modifying 3D Objects
When constructing 3D models, the only time the 2D commands ARRAY and MIRROR can be used is if all the objects that are selected in the command lie on the 2D plane of the current UCS. To array or mirror objects in 3D space, the corresponding 3D commands must be used.
3D Array
A 3D array, using the 3DARRAY command, is very similar to a 2D array, using the ARRAY command, that was taught in the AutoCAD 2D book. A rectangular and a polar 3D array can be preformed.
Rectangular Array
A 2D rectangular array uses rows and columns. In 3D, the third dimension of the array is called a level. Rows are along the Y axis, columns are along the X axis and levels are along the Z axis. Distance between the rows, columns and levels can be positive or negative. See Figure 9-1.
Polar Array
A 2D polar array only requires a XY point to array around while a 3D polar array, two XYZ points, a line or an axis must be specified to array around. See Figure 9-2.
3D Mirroring
A 3D mirror, using the MIRROR3D command, is very similar to a 2D mirror, using the MIRROR command, that was taught in the AutoCAD 2D book. A 2D mirror requires two XY points or a line to mirror around while a 3D mirror requires three XYZ points or a plane to mirror around. See Figure 9-3.
AutoCAD Command: 3DARRAY
The 3DARRAY command is used to array an object(s) in 3D space.
Shortcut: none
AutoCAD Command: MIRROR3D
The MIRROR3D command is used to mirror an object(s) in 3D space.
Shortcut: none
WORK ALONG: Creating a 3D Rectangular Array
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 09-1.
Step 3
Set layer: Model as the current layer.
Step 4
Using the figures as a reference, draw the wireframe model. Note the location of the WCS. (Figure Step 4A and 4B)
Step 5
Using the figures as a reference, draw the circle and then copy it to create a hole through the Front view. (Figure Step 5A, 5B, and 5C)
MUST KNOW: When you use the 3DARRAY command, ensure that object snap is disabled as it may affect the array by snapping to an unwanted existing object.
Step 6
Study the figure. It shows the hole pattern that will be used in the 3D ARRAY command. (Figure step 6)
Step 7
Ensure that Osnap is disabled.
Step 8
Ensure that the current UCS is set to the Front and enter the 3DARRAY command, as shown below, to array the holes. Your finished drawing should appear as shown. (Figure Step 8A and 8B)
Command: 3DARRAY
Select objects:
Specify opposite corner: 2 found
(Select the two circles.)
Select objects:
Enter the type of array [Rectangular/Polar] <R>:
(Rectangular array)
Enter the number of rows (—) <1>: 2
Enter the number of columns (|||) <1>: 11
Enter the number of levels (…) <1>: 2
Specify the distance between rows (—): -0.75
(In the negative Y direction.)
Specify the distance between columns (|||): 1
(In the positive X direction.)
Specify the distance between levels (…): -7.5
(In the negative Z direction.)
Command:
WORK ALONG: Creating a 3D Polar Array
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 09-2.
Step 3
Draw all model objects on layer: Model and all construction objects on layer: Construction. (Figure Step 3A, 3B, and 3C)
Step 4
Set the current UCS to Front and change the current view to Front. Draw three circles and a construction line from the centre to the quad as shown in the figure. Take all of the sizes from the multiview drawing. (Figure Step 4)
Step 5
Using the ARRAY command, array the construction line 192 times around. Use the centre of the circle as the basepoint for the array. (Figure Step 5)
Step 6
On layer: Model, draw two gear teeth by drawing lines from the intersection of the lines and the circles. (Figure Step 6)
Step 7
Turn layer: Construction off and your drawing should appear as shown in the figure. (Figure Step 7)
Step 8
Trim the two outer circles to form the repeat pattern of one gear tooth. (Figure Step 8)
Step 9
Change the current view to SE Isometric. (Figure Step 9)
Step 10
Copy all objects 0.5 inches in the -Z direction. 0.5 is the thickness of the gear. (Figure Step 10)
Step 11
Add lines to complete the gear tooth. (Figure Step 11)
Step 12
Enter the 3DARRAY command, as shown below, to complete the wireframe model of the gear. (Figure Step 12A and 12B)
Command: 3DARRAY
Select objects:
Specify opposite corner: 12 found
(Select the lines that make one gear tooth in a window.)
Select objects:
Enter the type of array [Rectangular/Polar] <R>:P
(Polar array.)
Enter the number of items in the array: 32
Specify the angle to fill (+=ccw, -=cw) <360>:
(Accept the default.)
Rotate arrayed objects? [Yes/No] <Y>:
(Accept the default.)
Specify centre point of array: (cen) P1
Specify second point on axis of rotation: (cen) P2
(From centre to centre of the circles defines the endpoints of a line to be used as the axis of the array.)
Command:
Step 13
Save and close the drawing.
WORK ALONG: Creating a 3D Mirror
Step 1
Open the drawing: AutoCAD 3D Workalong 09-1. The drawing should appear as shown in the figure. (Figure Step 1)
Step 2
Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 09-3.
Step 3
Enter the MIRROR3D command, as shown below, to mirror the model. (Figure Step 3)
Command: MIRROR3D
Select objects:
Specify opposite corner: 124 found
(Select all object in the model in a window.)
Select objects:
Specify first point of mirror plane or [Object/Last/Zaxis/View/XY/YZ/ZX/3points] <3points>: (end) P1
Specify second point on mirror plane: (end) P2
Specify third point on mirror plane: (end) P3
Delete source objects? [Yes/No] <N>:
(Accept the default.)
Command:
Step 4
The completed mirrored model is shown in the figure. (Figure Step 4A and 4B)
Step 5
Save and close the drawing.
Drafting Lesson: Break Lines
To simplify or speed up drawing orthographic views of a model, sometimes views are only partially drawn. In these cases, the cut off portion of the view is not required for the reader to visualize or construct the model. See the figures for examples of short and long break lines.
Key Principles
Key Principles in Module 9
1. The third dimension of a 3D array is called a level.
2. When rotating in 3D, you must rotate around two XYZ points or a line.
3. When mirroring in 3D, you must mirror around a three XYZ points or a plane.
4. Always disable object snap when executing a 3D array.
Lab Exercise 9-1
Time allowed: 50 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 09-1 3D Layout Metric Millimeters
Step 1
Draw all construction objects on layer: Construction.
Step 2
Draw all model objects on layer: Model.
Step 3
Draw a wireframe model of the object shown in the figure. (Figure Step 3A and 3B)
Step 4
Using the figure as a reference, anywhere in model space, draw a wireframe model of one nut and one bolt. (Figure Step 4A and 4B)
Step 5
Move one bolt and one nut to the bottom outside bolt location as shown in the figure. The bolt comes up from the bottom and nut is on top of the plane. (Figure Step 5A, 5B, 5C, and 5D)
Step 6
Array the nut and bolt to match the figure. (Figure Step 6)
Step 7
Mirror the completed model. (Figure Step 7)
Step 8
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.
Step 9
Change the current UCS to World and check the model with the key.
Step 10
Save and close the drawing.
Lab Exercise 9-2
Time allowed: 50 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 09-2 3D Layout English Inches
Step 1
Draw a wireframe model of the centre octagon and one arm as shown in the figures. Details of the arm are in Figure Step 1D Detail B and Figure Step 1E Detail A. (Figure Step 1A, 1B, 1C, 1D, and 1E)
Step 2
Array the arm as shown in the figure. (Figure Step 2)
Step 3
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.
Step 4
Change the current UCS to World and check the model with the key.
Step 5
Save and close the drawing.
Lab Exercise 9-3
Time allowed: 50 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 09-3 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model as shown in the figure. See the multiview drawing in Figure 1 Step B. (Figure Step 1A and 1B)
Step 2
Mirror the wireframe drawn in Step 1. Erase the extra lines and clean up the model to create one model. (Figure Step 2)
Step 3
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the current UCS to World and check the model with the key.
Step 4
Turn layer: Key off.
Step 5
Note the location of the UCS and rotate the model. (Figure Step 5)
Step 6
Note the location of the UCS and rotate the model. (Figure Step 6)
Step 7
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/02%3A_Part_2/2.03%3A_Module_9-_Arraying_and_Mirroring_3D_Models.txt |
Module 10: Viewing 3D Models – Part 2
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the VSCURRENT command to display 3D surface or solid models in the five predefined visual styles.
2. Apply the more advanced options of the 3DORBIT command.
3. Use the system variable VPCONTROL to enable the display the Viewport Controls menu and describe how this menu is used to set the current view and orientation of the model.
4. Enable the display of the ViewCube and describe how it used to change the display and orientation of the model.
Visual Styles
In the first nine modules, drawing wireframe models was taught. A wireframe model is a real-world 3D object represented by lines, circles, arcs, and/or plines located along the edges of the model. For that reason, you can see right through the model and see objects that would not be visible if the model was surfaced or solid. Think of it as the skeleton of a model.
In Modules 12 to 30, constructing surface and solid models is taught. AutoCAD software comes complete with five predefined visual styles. In this module, viewing surface and solid models using these five styles is covered.
The VSCURRENT command is used to set the current visual style that the model will be displayed. See Figure 10-1. You can change the current visual style as required.
AutoCAD Command: VSCURRENT
The VSCURRENT command is used to set the current visual style (shade mode) to be applied to a surface or solid model.
Shortcut: VS
WORK ALONG: Setting the Current Visual Style of a Model
Step 1
Using the NEW command, start a new drawing using the template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 10-1.
Step 3
Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. With the current UCS set in World, use the INSERT command to insert the block:
AutoCAD 3D Workalong 10-1 at the coordinates 0,0,0. Explode the block. Be careful to only explode it once.
Step 4
Set the current view to SE Isometric. Your model should now appear as shown in the figure. (Figure Step 4)
Step 5
Change the layer of both solid models to layer: Model.
Step 6
You should now have two solid models. To check this, open the Properties window and select one of the solid models. When selected, the object type in the top box of the Properties windows should indicate that the object is a 3D Solid. If the object type is anything else, exit and delete the drawing. Start this workalong again from Step 1. Be careful when using the EXPLODE command to explode the block only once. (Figure Step 6)
Step 7
If you are using Toolbars menus, enable the Visual Styles toolbar. If you are using the Ribbon Menus, click the Home tab. Enable the 2D Wireframe visual style icon. You can tell when the current visual style is 2D Wireframe by the appearance of the UCS icon. (Figure Step 7)
Step 8
Click the 3D Wireframe visual style icon. You can tell when the current visual style is 3D Wireframe by the appearance of the UCS icon. (Figure Step 8)
Step 9
Click the 3D Hidden visual style icon. Note how when the current visual style is 3D Hidden, the model appears solid and only displays the visible objects. (Figure Step 9)
Step 10
Change the layer of both solid models to layer: Solid 1.
Step 11
Click the Realistic visual style icon and note how when the current visual style is Realistic, the appearance of the model is the most basic realistic view of a shaded solid or surfaced model. (Figure Step 11)
Step 12
Click the Conceptual visual style icon and note how when the current visual style is Conceptual, the appearance of the solid model is more of an artistic look. (Figure Step 12)
Step 13
Delete the cylindrical solid model leaving only one solid model. Change the current visual style to Realistic and your model should now appear as shown in the figure. (Figure Step 13)
Step 14
If you are using Toolbar menus, enable the display of the Orbit toolbar. If you are using Ribbon menus, use the View-Orbit pull-down menu. Click the Constrained Orbit icon. (Figure Step 14A and 14B).
Step 15
When constrained orbit command is active, it displays the icon as shown in the figure. (Figure Step 15)
Step 16
Orbit the model and note how this command affects the position of the model. Press Esc to exit the command.
Step 17
Click the Free Orbit icon and orbit the model. Note how this command affects the position of the model. Press Esc to exit.
Step 18
Click the Continuous Orbit icon and use it to orbit the model. Read the Author’s Comments. (Figure Step 18)
Step 19
Set the current view to SE Isometric.
Step 20
Save and close the drawing.
MUST KNOW: Surface and solid models can be viewed in many visual styles. Models can be viewed as a wireframe, a hidden, or a solid. In a hidden style, the model will appear as it would in real life. It obstructs the lines and curves that are behind the visible surfaces. In the solid style, the model is shaded. A shaded model will be shaded with the same color as the model.
The VSCURRENT command controls which visual style is used to display the model. It will remain displayed in the that visual style until the current visual style is changed. Even if the drawing is closed and opened again, the visual style of the model remains as it was last set.
A model must be constructed as a surface or a solid to be viewed hidden or shaded. A wireframe model will only display in the 2D Wireframe or 3D Wireframe visual style. Constructing surface and solid models is taught in Modules 11 to 30.
AutoCAD System Variable: VPCONTROL
Enables or disables the display of the Viewport Controls menu.
Shortcut: none
WORK ALONG: Using the Viewport Controls Menu
Step 1
Open the drawing: AutoCAD 3D Workalong 10-1. (Figure Step 1)
Step 2
Enter the system variable VPCONTROL and set it to ON, as shown below.
Command: VPCONTROL
Enter new value for VPCONTROL <OFF>: ON
Command:
Step 3
Step 2 will enable the display of the Viewport Controls menu located in the top left corner of the Graphic window. (Figure Step 3A, 3B, and 3C)
Step 4
Click the small dash on the left side of the menu. This will pull down a list of menu items. Ensure that all items are disabled, as shown in the figure. (Figure Step 4)
Step 5
Click the View menu. It should read SE Isometric. This will pull down the list of the predefined views as shown in the figure. (Figure Step 5)
Step 6
Enable Top to change the current view of the model to the Top. (Figure Step 6A and 6B)
Step 7
Pull down the View menu and set the current view to SE Isometric. (Figure Step 7A and 7B)
Step 8
Click the Visual Style menu and in the pull down list, set the current visual style to 2D Wireframe. (Figure Step 8A and 8B)
Step 9
Click the Visual Style menu and in the pull down list, set the current visual style to Conceptual. (Figure Step 9A and 9B)
Step 10
Click the small dash on the left side of the menu to pull down the menu. Enable Navigation Bar. The Navigation Bar will display on the right side of the Graphic window as shown in the figure. (Figure Step 10A and 10B)
Step 11
Click the small arrow located at bottom right corner of the Navigation Bar to pull down its menu. Ensure that all six item are enabled as shown in the figure. (Figure Step 11)
Step 12
Click the small arrow again located at the bottom of the Navigation Bar to pull down its menu. Click the Docking positions item to display the flyout menu. Ensure the enabled items match the figure. (Figure Step 12)
Step 13
Open the Options dialogue box using the OPTIONS command. Enable the All other visual styles item under the Display the ViewCube, as shown in the figures. Click OK to close the dialogue box. (Figure Step 13A and 13B)
Step 14
Click the small dash on the left side of the menu to pull down the menu. Enable ViewCube. The ViewCube will display on the right side of the Graphic window, as shown in the figure. (Figure Step 14A and 14B)
Step 15
Save and close the drawing.
ViewCube is a valuable AutoCAD 3D tool that provides visual feedback of the current orientation of the model and a very quick and effective method of changing your viewpoint of the model. See Figure 10-3.
ViewCube can be used to restore and define the Home view of a model, switch between views of the model, projection modes and change its interactive behavior and appearance.
AutoCAD Command: NAVVCUBE
The NAVVCUBE command controls the visibility and display properties of the ViewCube tool.
Shortcut: none
WORK ALONG: Using ViewCube
Step 1
Open the drawing: AutoCAD 3D Workalong 10-1. (Figure Step 1)
Step 2
Click the small dash on the left side of the Viewport Controls menu. Ensure that ViewCube and Navigation Bar are enabled as shown in the figure. (Figure Step 2)
Step 3
The Graphic window should appear similar to the figure. (Figure Step 3)
Step 4
Ensure that the current view is set to SE Isometric.
Step 5
Click the arrow icon located on the lower right side of ViewCube. (Figure Step 5)
Step 6
In the pull-down menu, click Set Current View as Home. (Figure Step 6)
Step 7
Click the arrow again and click ViewCube Settings (Figure Step 7)
Step 8
Set the ViewCube Settings dialogue box as shown in the figure. (Figure Step 8)
Step 9
Move the cursor onto the top of ViewCube. When it turns blue, click it. The solid model’s current view will change to the Top view. (Figure Step 9A and 9B)
Step 10
Click the Home icon on ViewCube. It is the small house in the upper left corner. The model will now display the home view. For this model, it is SE Isometric. (Figure Step 10A and 10B)
Step 11
Using what you just learned, change the current view to Front. (Figure Step 11)
Step 12
Change the current view to Right. (Figure Step 12)
Step 13
Change the current view to the Home view. (Figure Step 13)
Step 14
Save and close the drawing.
USER TIP: ViewCube’s settings can also be adjusted in the Options dialogue box. See figure below.
Key Principles
Key Principles in Module 10
1. Surface and solid models can be viewed in many visual Models can be viewed as a wireframe, a hidden, or a solid. A shaded model will be shaded with the same color as the model.
2. The Viewport Controls menu is used to easily change the models orientation and visual style.
3. ViewCube is a valuable AutoCAD 3D tool that provides visual feedback of the current orientation of the model and a very quick and effective method of changing your viewpoint of the model.
4. ViewCube can be used to restore and define the Home view of a model, switch between views of the model, projection modes, and change its interactive behavior and appearance. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/02%3A_Part_2/2.04%3A_Module_10-_Viewing_3D_Models__Part_2.txt |
Module 11: Competency Test No. 2 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a three hour time limit, complete a written exam and a lab exercise without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. Where would the UCS plane be located if you used the Object UCS icon to select the current UCS?
1. It would lie perpendicular to the plane the object selected was on.
2. It would be on the WCS.
3. It would lie parallel with the current view.
4. It would lie on the plane that the selected object was on.
5. It would lie perpendicular to the WCS.
2. What type of axis must you select to mirror a 3 dimensional object?
1. level
2. plane
3. line
4. circle
5. point.
3. What command is used to polar array an object in 3D space?
1. 3DARRAY
2. ARRAY
3. REVOLVE
4. ROTATE
5. 3DORBIT
4. What is the Z-axis array called in a 3D array?
1. Level
2. Axis
3. Row
4. Elevation
5. Column
5. On what axis will the row be on in a 3D ARRAY?
1. X
2. Both the X and Y
3. Z
4. In the negative Z direction
5. Y
6. How many degrees apart are the XYZ axis in a 2 dimensional isometric drawing?
1. 60
2. 90
3. 120
4. 180
5. 360
7. How must a model be constructed if you want to view it in hidden mode using the VSCURRENT command? Choose the BEST answer.
1. As a solid model.
2. As a 3D wireframe.
3. As a 2D wireframe.
4. As a surface model.
5. As either a surface or solid model.
8. What is the current visual style shown in Figure 11-1?
1. 2D wireframe
2. 3D wireframe
3. Hidden
4. Flat
5. Gouraud
9. What is the current visual style shown in Figure 11-2?
1. 2D wireframe
2. 3D wireframe
3. Hidden
4. Flat
5. Gouraud
10. What type of axis must you select to rotate a 3 dimensional object?
1. level
2. plane
3. line
4. circle
5. point
Lab Exercise 11-1 OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 11-1 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the object shown in the multiview drawing. Set the current view to SE Isometric. (Figure Step 1A, 1B, 1C, and 1D)
Step 2
Mirror the original model so that the mirrored copy lies on top of the existing model as shown in the figure. (Figure Step 2)
Step 3
Rotate the model 90 degrees as shown in the figure. Note the location of the WCS in relation to the model, after the rotation. (Figure Step 3)
Step 4
Move the model to locate the front corner on the WCS. (Figure Step 4)
Step 5
Array the model to match the figure. Keep the location of the WCS in mind when you are executing the array. (Figure Step 5)
Step 6
On layer: Construction, draw a line from absolute coordinates X20,Y100,Z0 to the absolute coordinates X-5,Y100,Z0. (Note that X is negative 5). Before you draw it, ensure that the current UCS is World and keep in mind that the coordinates are absolute so do not use an @.
Step 7
Copy, rotate and locate one of the models at the end of the line you drew in Step 6. Locate it at the absolute coordinates X-5,Y100,Z0 (Note that X is negative 5) as shown in the figure. (Figure Step 7A and 7B)
Step 8
Array the model as shown in the figure. (Figure Step 8)
Step 9
Your complete model should match the figure. ( figure Step 9)
Step 10
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/02%3A_Part_2/2.05%3A_Module_11-_Competency_Test_No._2_Open_Book.txt |
Module 12: Surface Modeling – Part 1
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe surface faces and meshes and explain when and why they are used.
2. Apply the 3DFACE command to create simple face surfaced models.
Surface Models
A surface model is a 3D model with all of its outer surfaces covered with a thin coating. Think of it as an empty box with a balloon skin. All the sides that define its shape are covered but it is hollow on the inside. Unlike a solid model, the volume, weight, and centre of gravity of a surface model cannot be calculated by AutoCAD. Solid modeling is taught in Modules 17 to 31.
There are many reasons why surface models are constructed rather than solid models. A surface model can be used to create objects that have complex curved shapes which are difficult to construct as a solid models. For industries such as the automobile, aircraft, and ship design, surfaces are used as a crucial part of their CAD design. For 3D mapping, surface meshes are used to define the 3D physical shape of the earth.
Surface Types
A surface can be either created with a face or a mesh or a combination of the two. A surface face is a good method to create simple surfaces while a surface mesh works for all surfaces including complex and curved surfaces. Figure 12-1 shows a model covered with a surface mesh. Faces and meshes can be combined, on the same model, when surfacing a model by creating some of the surfaces with faces and some with meshes. Once a model is surfaced, it can be shaded as shown in Figure 12-2.
USER TIP: Although a model can be created with surfaces alone, it is much easier to construct it as a wireframe model first. Draw the wireframe on layer Model and when it is complete, create the surfaces and then freeze layer Model.
AutoCAD Command: 3DFACE
The 3DFACE command is used to create a surface face bounded by a minimum of three and a maximum of four edges.
Shortcut: 3F
USER TIP: There is no undo in the 3DFACE command. Be very careful when selecting the endpoints and plan the best order to create the surfaces before entering the command. If you make a mistake inside the command, all surface faces created in that command will be lost and you must reenter the command and start over.
WORK ALONG: Inserting Surface Faces
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 12-1.
Step 3
Set the current UCS to World. Enter the UNITS command and in the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block:
AutoCAD 3D Lab 01-2 at the coordinates 0,0,0. Explode the block and set the current view to SE Isometric. (Figure Step 3)
Step 4
Change the layer of all wireframe lines to layer: Model. (Figure Step 4)
Step 5
On layer: Construction, draw the construction lines to help you insert the surfaces. Keep in mind that the maximum number of sides that a face can be bound by is 4. Draw the lines on all six sides. (Figure Step 5)
Step 6
Set layer: Surface Face as the current layer. Enter the 3DFACE command, as shown below, to place a surface face on the wireframe model. Ensure you snap to the endpoints of the wireframe lines. (Figure Step 6)
Command: 3DFACE
Specify first point or [Invisible]: (end) P1
Specify second point or [Invisible]: (end) P2
Specify third point or [Invisible] <exit>: (end) P3
Specify fourth point or [Invisible]: (end) P4
(The surface face is defined by snapping to endpoints of existing wireframe lines. Pick points moving around the surface. Do not crisscross.)
Command:
Step 7
Enter the 3DFACE command as shown below. In this command, insert the common edges on the same plane as invisible. The figure shows the two edges (marked with an I) that should be inserted as invisible. (Figure Step 7)
Command: 3DFACE
Specify first point or [Invisible]: (end) P5
Specify second point or [Invisible]: (end) P6
Specify third point or [Invisible] <create three-sided face>: I
(You want the last edge to be invisible.)
Specify third point or [Invisible] <exit>: (end) P7
Specify fourth point or [Invisible] <create three-sided face>: (end) P8
Specify third point or [Invisible] <create three-sided face>: I
(You want the last edge to be invisible.)
Specify third point or [Invisible] <exit>: (end) P9
Specify fourth point or [Invisible] <create three-sided face>: (end) P10
Specify fourth point or [Invisible] <create three-sided face>: (end) P11
Specify fourth point or [Invisible] <create three-sided face>: (end) P12
Specify fourth point or [Invisible] <create three-sided face>: (end) P13
Specify fourth point or [Invisible] <create three-sided face>: (end) P14
Specify fourth point or [Invisible] <create three-sided face>: (end) P15
Specify fourth point or [Invisible] <create three-sided face>: (end) P16
Specify third point or [Invisible] <exit>:
Command:
Step 8
To check the surfaces you just inserted, set the current visual style to Realistic as shown in the figure. (Figure Step 8)
Step 9
Change the current visual style to 3D Wireframe.
Step 10
Using the 3DFACE command, add faces to completely surface the model. Ensure that you apply faces on the back and bottom. Turn layers: Model and Construction off.
Step 11
Change the current visual style to Realistic. Using the 3DFORBIT command, ensure that the complete model is surfaced. (Figure Step 11A and 11B)
Step 12
Save and close the drawing.
Key Principles
Key Principles in Module 12
1. A surface model is a 3D model with all of its outer surfaces covered with a A surface can be either created with a face or a mesh. A surface face is a good method to create simple surfaces while a surface mesh works for all surfaces including complex and curved surfaces.
2. Faces and meshes can be combined when surfacing a model by creating some of the surfaces with faces and some with
3. The 3DFACE command is used to create a surface face bounded by a minimum of three and a maximum of four The faces can be joined together with visible or invisible edges to make the faces appear as large as necessary.
Lab Exercise 12-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 12-1 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the object shown in the figures. (Figure Step 1A, 1B, and 1C)
Step 2
On layer: Surface Face, create surface faces on all surfaces including the back and bottom. Make all surface edges invisible.
Step 3
Freeze layers: Construction and Model.
Step 4
See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.
Step 5
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 6
Save and close the drawing.
Lab Exercise 12-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 12-2 N/A Millimeters
Step 1
Open the drawing: AutoCAD 3D Lab 05-2.
Step 2
Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Lab 12-2.
Step 3
On layer: Surface 3, create surface faces on each side including the back and bottom. (Figure Step 3A and 3B)
Step 4
Freeze layers: Construction and Model.
Step 5
See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.
Step 6
Save and close the drawing.
Lab Exercise 12-3
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 12-3 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 07-1.
Step 2
Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Lab 12-3.
Step 3
On layer: Surface 2, create surface faces on each side including the back and bottom. Surface all of it with mesh surfaces. (Figure Step 3A and 3B)
Step 4
When complete, freeze layers: Construction and Model.
Step 5
See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.
Step 6
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/03%3A_Part_3/3.01%3A_Module_12-_Surface_Modeling__Part_1.txt |
Module 13: Surface Modeling – Part 2
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe geometry defined meshes including rule surfaces, revolved surfaces, and tabulated surfaces.
2. Apply the RULESURF, REVSURF, and TABSURF commands to apply mesh surfaces to 3D models.
Geometry Defined Surface Meshes
Geometrically defined surface meshes use existing geometry that must be created before the surfaces. In almost all cases, the wireframe of the model is used as the existing geometry. There are four geometrically defined surface meshes that can be created in AutoCAD. They are the ruled surface, revolved surface, tabulated surface, and edge surface. The commands to create these meshes are RULESURF, REVSURF, TABSURF, and EDGESURF. The EDGESURF command is taught in Module 15.
To create a geometry defined surface mesh, start with the wireframe geometry and ensure that it is on its own layer. Surface the wireframe model on all sides, making sure that all exposed sides have a surface covering them. Think of the model as an object that must be made water tight.
Even the inside of a hole going through the model must have a surface applied on it. Place the surface meshes on their own layer. When the surfaced model is complete, freeze the layer containing the wireframe or the geometry leaving only the layer with the surface mesh displayed.
Ruled Surface
A ruled surface, inserted with the RULESURF command, is the most commonly used method to surface a model. To place a ruled surface, simply select two lines, a line and an arc, two arcs, or two circles to place the surface between. See Figure 13-1.
Revolved Surface
A revolved surface, inserted with the REVSURF command, is a surface created by revolving a profile around an axis. The profile can be a line, arc, circle, or an open or closed 2D polyline or 3D polyline. See Figure 13-2. The axis must be a line or an open 2D or 3D polyline. If a polyline is used as the axis, the REVSURF command will simply use a straight line between the start point and end point of the polyline.
Tabulated Surface
A tabulated surface, inserted with the TABSURF command, is a surface created by projecting a profile along a path. The profile defines the surface of the mesh as it follows the path. See Figure 13-3. The profile can be a line, arc, circle, ellipse, or an open or closed 2D or 3D polyline. The path can be a line or a polyline. If a polyline is used as the axis, the TABSURF command will simply use a straight line between the start point and end point of the polyline. The surface is drawn starting at the point on the profile closest to the point selected in the command.
Setting the Mesh Density
The mesh density represented by the lines, circles, or arcs that make the rows and columns of the surface mesh are controlled with the system variables SURFTAB1 and SURFTAB2. On flat surfaces, the density of the mesh is not that important but with curved or irregular shaped surfaces, the density is very important since the higher the setting, the more segments are used when creating circles and arcs. If the mesh is not dense enough, small gaps will be left where a curved surface meets a flat surface. See Figure 13-4.
AutoCAD Command: RULESURF
The RULESURF command is used to create a rule surface between two existing edges.
Shortcut: none
SURFTAB1 = YES
SURFTAB2 = No Effect
WORK ALONG: Inserting Ruled Surfaces
Step 1
Using the NEW command, start a new drawing using template: 3D Layout Metric.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 13-1.
Step 3
Set the current layer to: Model and the current visual style to 2D Wireframe.
Step 4
Draw a wireframe model of the multiview drawing. (Figure Step 4A and 4B)
Step 5
Set the system variable SURFTAB1 to 24 as shown below: Command: SURFTAB1
Enter new value for SURFTAB1 <8>: 24
Command:
Step 6
On layer: Construction, draw a line along the top edge of each side of the model. (Figure Step 6)
Step 7
Set layer: Surface 1 as the current layer. Enter the RULESURF command, as shown below, to insert a ruled surface. (Figure Step 7A and 7B)
Command: RULESURF
Current wire frame density: SURFTAB1=24
Select first defining curve: P1
Select second defining curve: P2
Command:
Step 8
Repeat the RULESURF command and insert surfaces all around the edge of the model. (Figure Step 8)
Step 9
Turn layer: Surface Off off and lock layers: Model and Construction. Select all of the surfaces inserted in Steps 7 and 8 and change their layer to: Surface Off. (Figure Step 9)
Step 10
Using what was just taught, insert ruled surfaces around the top of the object and inside of the hole as shown in the figure. (Figure Step 10).
Step 11
Change the layer of the surfaces inserted in Step 10 to layer: Surface Off.
Step 12
On layer: Construction, draw the construction lines on the top surface as shown in the figure. Ensure to snap to the endpoints of the lines and arcs. (Figure Step 12)
MUST KNOW: When using the RULESURF command, ensure that you select the objects closest to matching ends. If opposite ends are selected, the mesh will twist as shown in the figure.
Step 13
On layer: Surface 1, use the RULESURF command to insert the surfaces as shown in the figure. Change the surfaces the layer: Surface off. (Figure Step 13)
Step 14
On layer: Surface 1, use the RULESURF command to draw surfaces as shown in the figure. Change the layer of the surfaces to layer: Surface off. (Figure Step 14)
Step 15
On layer: Construction, draw a 180 degree arc on the top half of the circle. Ensure that you snap to the quads of the circle. To do that, ensure to locate the UCS on the same plane as the circle. (Figure Step 15)
Step 16
On layer: Surface 1, insert a ruled surface between the arcs. (Figure Step 16)
Step 17
Change the layer of the surface that you just drew to layer: Surface Off.
Step 18
Draw two construction lines and a construction arc on the bottom half of the circle. (Figure Step 18)
Step 19
On layer: Surface 1, insert a ruled surface. (Figure Step 19)
Step 20
On layer: Surface 1, insert the ruled surfaces as shown in the figure. (Figure Step 20)
Step 21
Change the layer of the existing surfaces to layer: Surface 1 until your model matches the figure. (Figure Step 21)
Step 22
Copy the surfaces from the front side of the model to back side. (Figure Step 22)
Step 23
Using what was just taught, complete surfacing the model. Ensure to surface the bottom of the model. When complete, change all the surfaces from layers: Surface off to Surface 1.
Step 24
Turn off all the layers except layer: Surface 1 and the model should appear as shown in the figure. (Figure Step 24)
Step 25
Set the current visual style to Realistic. (Figure Step 25)
Step 26
Save and close the drawing.
AutoCAD Command: REVSURF
The REVSURF command is used to create a surface of revolution by revolving an existing profile around an axis.
Shortcut: none
SURFTAB1 = YES
SURFTAB2 = YES
WORK ALONG: Inserting Revolved Surfaces
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 13-2. (Figure Step 2)
Step 3
Set the current layer to: Pline and the current visual style to 2D Wireframe.
Step 4
Change the current view to SE Isometric and the current UCS to Right.
Step 5
Using the multiview drawing as a reference, draw the right side cross section of the solid part of the object. (Figure Step 5)
Step 6
On layer: Construction, draw a line, of any length, from 0,0,0 along the X axis. Enable ortho mode to draw it faster. This is the centre of the model and will be used as the axis for the revolution. (Figure Step 6)
Step 7
Using the PEDIT command, as shown below, convert the lines of the model to a closed polyline.
Command: PE
Select polyline or [Multiple]:
(Select one line of the model.)
Object selected is not a polyline
Do you want to turn it into one? <Y>
(Press Enter to accept the default.)
Enter an option [Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]: J
(J for Join.)
Select objects: ALL
13 found
Select objects:
11 segments added to polyline
Enter an option [Open/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]:
Command:
Step 8
To ensure that you have successfully created a closed polyline, open the Properties window and select the polyline. The object type should read Polyline, all the objects should show as part of the polyline and the Closed property should indicate Yes. (Figure Step 8)
Step 9
Set the system variable SURFTAB1 to 64 and SURFTAB2 to 24 as shown below.
Command: SURFTAB1
Enter new value for SURFTAB1 <6>: 64
Command: SURFTAB2
Enter new value for SURFTAB2 <6>: 24
Command:
Step 10
Change the current layer to layer: Surface 1 and enter the REVSURF command as shown below. After you complete the command, your model should appear as shown in the figure. (Figure Step 10)
Command: REVSURF
Current wire frame density: SURFTAB1=64 SURFTAB2=24
Select object to revolve
(Select the closed polyline.)
Select object that defines the axis of revolution:
(Select the axis line.)
Specify start angle <0>:
(Accept the default of 0.)
Specify included angle (+=ccw, -=cw) <360>:
(Accept the default of 360.)
Command:
Step 11
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 12
Using the 3DFORBIT command, orbit the model and look at all sides. (Figure 12A and 12B)
Step 13
Save and close the drawing.
AutoCAD Command: TABSURF
The TABSURF command is used to create a surface mesh moving a profile along a path. Shortcut: none
SURFTAB1 = YES
SURFTAB2 = No Effect
WORK ALONG: Inserting Tabulated Surfaces
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 13-3.
Step 3
Set the current visual style to 2D Wireframe, the current view to SE Isometric, and the current UCS to World.
Step 4
Set layer: Construction as the current layer. Draw the model shown in the dimensioned model. These are the construction lines and arcs to be used to construct the model. When complete, your model will appear as shown in the figure. The length of the lines that appear dashed in the dimensioned model are not important since they are axis lines only. They are always drawn in the Z direction of the current UCS. They can be drawn any length as continuous linetype. (Figure Step 4A, 4B, and 4C)
Step 5
Set the current UCS to Front and then draw a model of the object shown in the dimensioned drawing. The drawing should appear as shown in the figure. Draw the model anywhere in model space. Its location is not important. (Figure Step 5A and 5B)
Step 6
Change the lines and arcs into two closed polylines using the PEDIT command. Check them using the Properties window. (Figure Step 6)
Step 7
On layer: Construction, draw in two construction lines from midpoint of the lines to find the exact centre of the object. (Figure Step 7)
Step 8
Make three additional copies of the model and rotate them to lay on different UCS planes. Their location in 3D space is not important. (Figure Step 8)
Step 9
Your drawing should appear similar to the figure. (Figure Step 9)
Step 10
Copy the objects onto the construction lines. Ensure that the midpoint of the object (the intersections of the construction lines) aligns to the endpoints of the lines and arcs. (Figure Step 10)
Step 11
With the UCS located on the Front, SURFTAB1 set to 48 and layer: Surface 1 as the current layer, enter the TABSURF command, as shown below, to create the surface for the inside of the tube. (Figure Step 11)
Command: TABSURF
Current wire frame density: SURFTAB1=48
Select object for path curve:
(Select the inside polyline.)
Select object for direction vector:
(Select the construction axis line. Ensure you select it closer to the end where the object your are tabulating is located.)
Command:
Step 12
Set the current visual style to Realistic. (Figure Step 12)
Step 13
Using the TABSURF command, create the surface for the outside of the tube. (Figure Step 13)
Step 14
Enter the REVSURF command, as shown below, to construct the inside of the tube around the first corner. First change the layer of the straight tube surfaces constructed in Steps 11 to 13 to layer: Surface Off. (Figure Step 14)
Command: REVSURF
Current wire frame density: SURFTAB1=48 SURFTAB2=6
Select object to revolve:
(Select the inside polyline.)
Select object that defines the axis of revolution
(Select the axis line.)
Specify start angle <0>:
(Accept the default.)
Specify included angle (+=ccw, -=cw) <360>: -90
Command:
Step 15
Using what was just taught, construct the outside of the tube and change the layers of the surfaces until the model appear as shown in the figure. (Figure Step 15)
Step 16
Using what was just taught, complete the model. (Figure Step 16)
Step 17
Turn off layers: Model and Construction and your completed model will appear as shown in the figure. (Figure Step 17)
Step 18
Save and close the drawing.
USER TIP: Although any surfacing command can be used to create the surfaces, the RULESURF command is the easiest and fastest to use for most surfaces. To shorten the modeling time, use it whenever possible.
Key Principles
Key Principles in Module 13
1. Geometrically defined surface meshes use existing geometry that must be created before the surfaces. In almost all cases, you will use the wireframe of the model as the existing geometry.
2. Although any surfacing command can be used to create a surface, the RULESURF command is the easiest and fastest to use for most surfaces.
3. When using the RULESURF command, ensure that you select the objects closest to matching If opposite ends are selected, the mesh will twist.
4. The mesh density represented by the lines, circles or arcs that make the rows and columns of the surface mesh are controlled with the system variables SURFTAB1 and SURFTAB2.
Lab Exercise 13-1
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 13-1 3D English Inches
Step 1
Draw a wireframe of the object shown in the figure. (Figure Step 1)
Step 2
Pick appropriate mesh densities and on layer: Surface 2, create surface meshes on all surfaces including back and bottom. (Figure Step 2)
Step 3
Freeze layers: Construction and Model.
Step 4
Set the current visual style to Realistic. Use the 3DORBIT command to check that the model is surfaced on all sides.
Step 5
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 6
Save and close the drawing.
Lab Exercise 13-2
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 13-2 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 04-1.
Step 2
Save the drawing with the name: AutoCAD 3D Lab 13-2.
Step 3
On layer: Surface 5, create surface meshes on all surfaces including back and bottom. (Figure Step 3)
Step 4
Freeze layers: Construction and Model.
Step 5
Set the current visual style to Realistic. Use the 3DFORBIT command to check that the model is surfaced on all sides.
Step 6
Save and close the drawing.
Lab Exercise 13-3
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 13-3 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 08-1.
Step 2
Save the drawing with the name: AutoCAD 3D Lab 13-3.
Step 3
On layer: Surface 1, create surfaces on each side including back and bottom. (Figure Step 3)
Step 4
Freeze layers: Construction and Model.
Step 5
Set the current visual style to Realistic. Use the 3DFORBIT command to check that the model is surfaced on all sides.
Step 6
Save and close the drawing.
Lab Exercise 13-4
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 13-4 3D Layout Metric Millimeters
Step 1
On layer: Pline, draw the cross section of the top half of the model on the right side UCS. (Figure Step 1A and 1B)
Step 2
Create a surface revolution on layer: Surface 1. (Figure Step 2)
Step 3
Freeze layers: Pline and Construction.
Step 4
Set the current visual style to Realistic. Use the 3DORBIT command to check that the model is surfaced on all sides.
Step 5
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 6
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/03%3A_Part_3/3.02%3A_Module_13-_Surface_Modeling__Part_2.txt |
Module 14: Surface Modeling – Part 3
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe a complex surface mesh and a region.
2. Apply the 3DMESH, REGION, and SUBTRACT commands.
Drawing Complex Surface Meshes
When an irregular complex mesh cannot be drawn using a geometrically generated surface, the 3DMESH command can be used to create it. The 3DMESH command uses a grid made of XYZ coordinates to generate the surface mesh. This command is used extensively when creating 3D topographical maps. It is also used in automobile and airplane design.
AutoCAD Command: 3DMESH
The 3DMESH command is used to create an irregular complex surface mesh from a grid of XYZ coordinates.
Shortcut: none
WORK ALONG: Drawing 3D Surface Meshes
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 14-1.
Step 3
Set layer: Model as the current layer.
Step 4
Set the current visual style to 2D Wireframe, the current UCS to World, and the current view to SE Isometric. (Figure Step 4)
Step 5
Draw a 5 X 4 grid as shown in the figure. Draw the grid lines 1 inch apart along both the X and Y axis. (Figure Step 5)
Step 6
Set layer: Surface 1 as the current layer and using Figure Step 6A as a reference, enter the 3D MESH command, as shown below, to create the 3D mesh. When complete, your drawing should appear as shown in the figure. (Figure Step 6A and 6B)
4Figure Step 6BCommand: 3DMESH
Enter size of mesh in M direction: 5
(5 columns in the X direction. Count the grid lines not the spaces.)
Enter size of mesh in N direction: 4
(4 rows in the Y direction. Count the grid lines, not the spaces.)
Specify location for vertex (0, 0): 0,0,0.2
(Enter the XYZ coordinates stating at bottom left corner which is X0Y0Z0.2. Then work up the Y axis to the top and then jump back down to X1,Y0.)
Specify location for vertex (0, 1): 0,1,0.5
(The 0.5 is entered here for clarity. If you enter .5 it will do the same thing.)
Specify location for vertex (0, 2): 0,2,0.4
Specify location for vertex (0, 3): 0,3,0.3
Specify location for vertex (1, 0): 1,0,0.1
Specify location for vertex (1, 1): 1,1,0.3
Specify location for vertex (1, 2): 1,2,0.6
Specify location for vertex (1, 3): 1,3,0.5
Specify location for vertex (2, 0): 2,0,0
Specify location for vertex (2, 1): 2,1,-0.2
Specify location for vertex (2, 2): 2,2,-0.3
Specify location for vertex (2, 3): 2,3,-0.5
Specify location for vertex (3, 0): 3,0,0.1
Specify location for vertex (3, 1): 3,1,0.2
Specify location for vertex (3, 2): 3,2,0.2
Specify location for vertex (3, 3): 3,3,0.2
Specify location for vertex (4, 0): 4,0,0.3
Specify location for vertex (4, 1): 4,1,0.7
Specify location for vertex (4, 2): 4,2,0.5
Specify location for vertex (4, 3): 4,3,0.4
Command:
Step 7
Turn layer Model off and set the current visual style to: Realistic. Your model should appear similar to the figure. (Figure Step 7)
Step 8
Turn layer: Surface 1 off and layer: Model on. Set the current layer to: Model. With the UCS set to World, draw lines from the each grid vertex in the Z distance. See Figure Step 6A for the Z value. Be careful as some are positive and some are negative. When the Z is 0, you do not have to draw anything. For example, the line at X0Y0 should be drawn 0.2 inches in the positive Z direction. When complete, the model should appear as shown in figure. (Figure Step 8)
Step 9
Set layer: Surface 2 as the current layer and enter the 3DMESH as shown below. (Figure Step 9)
Command: 3DMESH
Enter size of mesh in M direction: 5
Enter size of mesh in N direction: 4
Specify location for vertex (0, 0): (end) P1
(With osnap enabled, snap to the end of the Z line. You may have to zoom in to ensure you are snapping to the correct end of the line.)
Specify location for vertex (0, 1): (end) P2
Specify location for vertex (0, 2):(end) P3
Specify location for vertex (0, 3):(end) P4
Specify location for vertex (1, 0):(end) P5
Specify location for vertex (1, 1):(end) P6
(Continue until you complete the grid.)
Command:
Step 10
Set the current visual style to: Realistic. Your model should appear similar to the figure. (Figure Step 10)
Step 11
Save and close the drawing.
Regions
A region is a 2D solid and is created using a closed polyline, circle, ellipse or spline as the boundary. A region must lie on a 2D plane. See Figure 14-1.
While regions are not technically surfaces, they will shade and can be rendered, therefore, can be used to surface a model.
If the system variable DELOBJ is set to 1, AutoCAD will delete the closed object that was used as the boundary to create the region. In most cases, it is important for you to set this variable to 0 to retain the original object used to create the region.
MUST KNOW: If the system variable DELOBJ is set to 1, the REGION command will delete the closed object that was used as the boundary to create the region. In most cases, it is important to set this variable to 0 to retain the original object(s).
AutoCAD Command: REGION
The REGION command is used to create a 2D solid within a closed object.
Shortcut: REG
AutoCAD Command: SUBTRACT
The SUBTRACT command is used to subtract one solid from another.
Shortcut: SU
WORKALONG: Inserting and Subtracting Regions
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 14-2. (Figure Step 2)
Step 3
Set layer: Model as the current layer, the current view to SE Isometric, the current UCS to Top, and the current visual style to 2D Wireframe.
Step 4
Draw the wireframe model of the multiview drawing. (Figure Step 4)
Step 5
Enter the DELOBJ system variable, as shown below, and set it 0. Command: DELOBJ
Enter new value for DELOBJ <1>: 0
Command: DELOBJ
Enter new value for DELOBJ <0>:
Command:
Step 6
Move the UCS to lie on top of the model as shown in the figure. Ensure that the positive Z axis is up and it is located at the centre of the circle. (Figure Step 6)
Step 7
Using what you learned earlier, use the PEDIT command to convert the lines and arcs to closed polylines. Check the objects with the Properties window to ensure that they are closed. (Figure Step 7)
Step 8
Delete all of the objects except the circles on the bottom of the model and then copy the plines you just created to the bottom. (Figure Step 8)
Step 9
Set layer: Surface 1 as the current layer and enter the REGION command, as shown below, to create regions for the five closed objects on top of the model.
Command: REGION
Select objects: 1 found
(Select each object, by picking them one at a time.)
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
Select objects: 1 found, 4 total
Select objects: 1 found, 5 total
Select objects:
5 loops extracted.
5 Regions created.
Command:
Step 10
Set the current visual style to: Realistic. Your model should appear as shown in the figure. (Figure Step 10)
Step 11
Using the REGION command, insert a region using the outside closed polyline. (Figure Step 11)
Step 12
Using the SUBTRACT command, subtract the five inner regions that you created in Step 9 from the region you created in Step 11. (Figure Step 12)
Command: SUBTRACT
Select solids and regions to subtract from ..
Select objects: 1 found
(Select the large region.)
Select objects:
(Press Enter to indicate you have finished selecting.)
Select solids and regions to subtract ..
Select objects: 1 found
(Select each of the five smaller regions one at a time.)
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
Select objects: 1 found, 4 total
Select objects: 1 found, 5 total
Select objects:
Command:
Step 13
Ensure that layer: Surface Off is off and then change the layer of the region you just created to layer: Surface Off. Your model will now appear as shown in the figure. (Figure Step 13)
Step 14
Click the UCS Origin icon and then snap to the centre of the circle on the bottom of the object. (Figure Step 14)
Step 15
Click the Rotate X Axis UCS icon on the UCS toolbar and rotate it 180 degree rotation. This will rotate the UCS so that the positive Z direction is pointing down. (Figure Step 15)
Step 16
Using the 3DORBIT command, rotate the model around about 180 degrees and then using what you learned in Steps 10 to 12, insert the regions on the bottom. Subtract the inner regions as you did before. (Figure Step 16)
Step 17
Change the layer of the regions to layer: Surface Off and then using the RULESURF command, create surfaces on the edges and holes in the model. Create the surfaces on layer: Surface 1. (Figure Step 17)
Step 18
Turn layers: Model and Construction off and change the layer of the regions to layer: Surface 1. Your completed model should appear as shown in the figure. Use the 3DORBIT command to check that the complete model is surfaced. (Figure Step 18)
MUST KNOW: A region is a two-dimensional solid created within a closed object. Regions can only be created within closed plines, circles, ellipses and splines. The complete region must lay on one plane. A region is actually a 2D solid.While regions are not technically surfaces, they will shade and can be rendered, therefore, can be used to surface a model.If the system variable DELOBJ is set to 1, AutoCAD will delete the closed object that was used to create the region. In most cases, it is important for you to set this variable to 0 to retain your original wireframe object used to create the region.
Key Principles
Key Principles in Module 14
1. A region is a two-dimensional solid created using a closed polyline, circle, ellipse, or spline as the Each region must lie on one plane.
2. While regions are not technically surfaces, they will shade and can be rendered, therefore, can be used to surface a A shaded region will only be visible when viewed from the positive Z direction of the UCS that was current when the region was created.
Lab Exercise 14-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 14-1 3D Layout Metric Millimeters
Step 1
On layer: Model, draw the grid shown below. The grid lines are an equal distance apart. (Figure Step 1A and 1B)
Step 2
On layer: Surface 2, draw a 3D mesh on the grid using the 3D MESH command. The Z values are displayed at each vertex in Figure Step 1B. Set the current visual style to Realistic. It should appear as shown in the figure. (Figure Step 2)
Step 3
Set the current visual style to 3D Wireframe. Turn layer Surface 2 off and on layer: Model, draw lines representing the Z coordinates. (Figure Step 3)
Step 4
On layer: Surface 3, draw a 3D mesh on the grid using the 3D MESH command and snapping to ends of the Z coordinates. Set the current visual style to Realistic. (Figure Step 4)
Step 5
Turn layer: Model off and the completed mesh should appear as shown in the figure. (Figure Step 5)
Step 6
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 7
Save and close the drawing.
Lab Exercise 14-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 14-2 3D Layout Metric Millimeters
Step 1
Draw a wireframe model of the object. (Figure Step 1A and 1B)
Step 2
Use the 2D ARRAY command to speed the model construction.
Step 3
On layer: Surface 1, create regions for the top and bottom of the model.
Step 4
On layer: Surface 1, create ruled surfaces for the remainder of the surfaces. Ensure that the complete model is surfaced.
Step 5
Set the visual style to: Realistic.
Step 6
Freeze layers: Construction and Model.
Step 7
Using the 3DORBIT command, check the model for completeness
Step 8
Set the Insertion Units, change the current UCS to World and check the model with the key.
Lab Exercise 14-3
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 14-3 N/A Millimeters
Step 1
Open the drawing: AutoCAD 3D Lab 03-2.
Step 2
Save the drawing with the name: AutoCAD 3D Lab 14-3.
Step 3
On layer: Surface 1, create regions and surfaces on all sides and holes. (Figure Step 3)
Step 4
Set the visual style to Realistic.
Step 5
Freeze layers: Construction and Model.
Step 6
Using the 3DORBIT command, check the model for completeness
Step 7
Save and close the drawing.
Lab Exercise 14-4
Time allowed: 50 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 14-4 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 09-3.
Step 2
Save the drawing with the name: AutoCAD 3D Lab 14-4.
Step 3
On layer: Surface 2, create regions and surfaces on all sides and holes. (Figure Step 3)
Step 4
Set the visual style to: Realistic.
Step 5
Freeze layers: Construction and Model.
Step 6
Using the 3DORBIT command, check the model for completeness
Step 7
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/03%3A_Part_3/3.03%3A_Module_14-_Surface_Modeling__Part_3.txt |
Module 15: Surface Modeling – Part 4
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe a 3D polyline and how it compares to a 2D polyline.
2. Apply the 3DPOLY command and draw 3D polylines.
3. Apply the EDGESURF command.
4. Apply the PEDIT, SURFTYPE, SPLFRAME, SURFV, and SURFU commands and system variables to modify the appearance of 3D meshes.
3D Polylines
Since the release of AutoCAD 14, polylines created with the PLINE command have been created as lightweight polylines. Sometimes called a 2D polylines, shown in Figure 15-1, lightweight polyline are greatly improved over the older heavyweight or 3D polylines. A 2D polyline must lay on a single plane.
A 3D polyline is created with the 3DPOLY command using XYZ coordinates to locate each of the vertices. See Figure 15-2. A 3D polyline is not restricted to lay on the same plane. It requires a larger part of the drawings database compared to a 2D polyline. For that reason, use 3D polylines only when absolutely required in 3D modeling. 3D polylines must be constructed with lines only and cannot contain arcs or be given a width.
AutoCAD Command: 3DPOLY
The 3DPOLY command is used to create 3D polylines.
Shortcut: none
AutoCAD Command: EDGESURF
The EDGESURF command is used to create a surface mesh by selecting four drawing objects. The drawing objects can be lines, arcs, 2D polylines, and 3D polylines.
Shortcut: none
WORK ALONG: Surfacing Models Using 3D Polylines and Edge Surfaces
Step 1
Open the drawing: AutoCAD 3D Workalong 14-1.
Step 2
Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 15-1.
Step 3
Turn off all layers except layer: Model.
Step 4
Set the current visual style to 2D Wireframe, the current UCS to World and the current view to SE Isometric. Your model should appear as shown in the figure. (Figure Step 4)
Step 5
Set layer: 3D Pline as the current layer. Enter the 3DPOLY command, as shown below, to draw 3D polylines between all of the Z coordinates on the grid in both the X and the Y direction. (Figure Step 5)
Command: 3DPOLY
Specify start point of polyline: (end) P1
Specify endpoint of line or [Undo]: (end) P2
Specify endpoint of line or [Undo]: (end) P3
Specify endpoint of line or [Undo]: (end) P4
Specify endpoint of line or [Close/Undo]:
Command: 3DPOLY
Specify start point of polyline: (end) P5
Specify endpoint of line or [Undo]: (end) P6
Specify endpoint of line or [Undo]: (end) P7
Specify endpoint of line or [Undo]: (end) P8
Specify endpoint of line or [Close/Undo]:
Command:
Step 6
Continue drawing the remainder of the 3D polylines on the Y axis. (Figure Step 6)
Step 7
Draw 3D polylines between all the Z coordinates in the X direction until you complete the grid. (Figure Step 7)
Step 8
Turn layer: Model off and your model should appear as shown in the figure. Using the EXPLODE command and a window, explode the 3D plines to convert them into lines. (Figure Step 8)
Step 9
Change the view to Top. (Figure Step 9)
Step 10
Set layer: Surface 1 as the current layer. Enter the 3DMESH command, as shown below, to create the mesh. (Figure Step 10)
Command: 3DMESH
Enter size of mesh in M direction: 5
Enter size of mesh in N direction: 4
Specify location for vertex (0, 0): (end) P1
Specify location for vertex (0, 1): (end) P2
Specify location for vertex (0, 2): (end) P3
Specify location for vertex (0, 3): (end) P4
Specify location for vertex (1, 0): (end) P5
Specify location for vertex (1, 1): (end) P6
Specify location for vertex (1, 2): (end) P7
Specify location for vertex (1, 3): (end) P8
(Continue to cover the complete mesh.)
Command:
Step 11
Set the current visual style to Realistic and the current view to SE Isometric. (Figure Step 11)
Step 12
Set the current visual style to 2D Wireframe and turn layer: Surface 1 off. You will only see the 3D polylines. (Figure Step 12)
Step 13
Set the system variables SURFTAB1 to 6 and SURFTAB2 to 6.
Step 14
On layer: Surface 4, use the EDGESURF command, as shown below, to create a surface mesh on one grid square. (Figure Step 14)
Command: EDGESURF
Current wire frame density: SURFTAB1=6 SURFTAB2=6
Select object 1 for surface edge: P1
Select object 2 for surface edge: P2
Select object 3 for surface edge: P3
Select object 4 for surface edge: P4
Command:
Step 15
Set the current visual style to Realistic. (Figure Step 15)
Step 16
On layer: Surface 4, using the EDGESURF command, create surfaces in all grid squares to cover the model. When complete, the model will appear as shown in the figure. (Figure Step 16)
Step 17
Save and close the drawing.
Modifying the Appearance of Surface Meshes
There are several system variables that can be used to modify or change the appearance of existing surface meshes or changing their mesh density. The PEDIT command and SURFV, SURFU, SURFTYPE, and SPLFRAME system variables are used to smooth and change the setting for the appearance of and mesh density of 3D meshes. If the desired results cannot be obtained using these system variables, it is sometime easier and faster to erase the surface and construct it again using a smaller base grid.
System Variable: SURFV and SURFU
The SURFV and SURFU system variables are used to set the surface mesh density of the M and N directions when the Smooth option is selected in the PEDIT command.
Shortcut: none
SURFU sets the M direction.
SURFV sets the N direction.
System Variable: SURFTYPE
The SURFTYPE system variable is used to control the method AutoCAD fits the surface when the Smooth option is selected in the PEDIT command.
Shortcut: none
It has the following settings:
5 – Quadratic B-spline surface
6 – Cubic B-spline surface
8 – Bezier surface
System Variable: SPLFRAME
The SPLFRAME command is used to control the display of splines and meshes that have been smoothed.
Shortcut: none
It has the following settings:
0 – Enables the display of the smoothed meshes and spline-fit
1 – Disables the display of the smoothed meshes or spline-fit It will display the original mesh. It does not display the invisible edges of 3D faces or polyface meshes.
WORK ALONG: Modifying the Appearance of Surface Meshes
Step 1
Open drawing: AutoCAD 3D Workalong 15-1. Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 15-2.
Step 2
Turn off all layers except layer: Surface 1. Set the current visual style to Realistic, the current UCS to World and the current view to SE Isometric. (Figure Step 2)
Step 3
Set the current visual style to 3D Wireframe. (Figure Step 3)
Step 4
Enter the commands shown below and your model will appear as shown in the figure. (Figure Step 4)
Command: SURFV
Enter new value for SURFV <6>: 12
Command: SURFU
Enter new value for SURFU <6>: 24
Command: PEDIT
Select polyline or [Multiple]:
(Select the mesh.)
Enter an option [Edit vertex/Smooth surface/Desmooth/Mclose/Nclose/Undo]: S
Generating segment 2… Command: REGEN
REGEN Regenerating model.
Command:
Step 5
Enter the commands shown below. The model should display as it was when you started this exercise. (Figure Step 5)
Command: SPLFRAME
Enter new value for SPLFRAME <0>: 1
Command: REGEN Regenerating model.
Command:
Step 6
Enter the commands shown below and your model will display as shown in the figure. (Figure Step 6)
Command: SPLFRAME
Enter new value for SPLFRAME <1>: 0
Command: REGEN
Regenerating model
Command:
Step 7
Enter the commands shown below and your model will display as shown in the figure. (Figure Step 7)
Command: SURFTYPE
Enter new value for SURFTYPE <6>: 5
Command: PEDIT
Select polyline or [Multiple]:
(Select the mesh.)
Enter an option [Smooth surface/Desmooth/MOpen/MClose/NOpen/NClose/Undo]: S
Command:
Step 8
Enter the commands shown below and your model will display as shown in the figure. (Figure Step 8)
Command: SURFTYPE
Enter new value for SURFTYPE <5: 8
Command: PEDIT
Select polyline or [Multiple]:
(Select the mesh.)
Enter an option [Smooth surface/Desmooth/MOpen/MClose/NOpen/NClose/Undo]: S
Command:
Step 9
Set the current visual style to Realistic. (Figure Step 9)
Step 10
Save and close the drawing.
Key Principles
The Key Principles in Module 15
1. Sometimes called a 2D polyline, a lightweight polyline is greatly improved over the older heavyweight or 3D A 2D polyline must lay on a single plane.
2. A 3D polyline is created with the 3DPOLY command using XYZ coordinates to locate each A 3D polyline is not restricted to lay on the same plane.
3. The command PEDIT and system variables SURFV, SURFU, SURFTYPE, and SPLFRAME are used to smooth and change the setting for the appearance of and mesh density of 3D meshes.
Lab Exercise 15-1
Time allowed: 3 hours.
Drawing Name Template Units
AutoCAD 3D Lab 15-1 3D Layout English Feet
Step 1
In this lab exercise, you will be creating a surface mesh on a plot of land that is 2500 X 2500 feet. There is an exiting 100 ft. road on the south side of the property. (Figure Step 1)
Step 2
Start a new drawing, using the template 3D Layout English. Insert the block: AutoCAD 3D Lab 15-1. Explode the block.
Step 3
Change the layer of all objects to layer: Model. (Figure Step 3)
Step 4
Change the current view to SE Isometric. (Figure Step 4)
Step 5
The 2D grid is located at sea level or Z=zero and is divided equally every 100 ft.
Step 6
On the layer: 3D Pline, draw 3D polylines between the top of each of the Z coordinate lines to construct a digital terrain model of the property as shown below. Try rotating the grid and lines to different positions to find the best view to insert the 3D polylines. (Figure Step 6)
Step 7
Turn off all layers except layers: 3D Pline and Surface 2.
Step 8
Change the view to Top. (Figure Step 8)
Step 9
Set layer: Surface 2 as the current layer. Using the EXPLODE command and a window, explode the 3D plines to convert them into lines.
Step 10
Using the 3DMESH command, draw a mesh by snapping to each of the 625 endpoints. Ensure to select the points in the correct sequence and zoom in to select very accurately. If an error is made, start over again. This will require about 30 minutes of uninterrupted work. Turn layer: 3D Pline off. Set the current view to SE Isometric and the current visual style to Realistic. (Figure Step 10)
Step 11
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/03%3A_Part_3/3.04%3A_Module_15-_Surface_Modeling__Part_4.txt |
Module 16 Competency Test No.3 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a five hour time limit, complete a written exam and the lab exercises without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. In a surface mesh, what is the intersection of a column and a row called?
1. Crossing
2. Point
3. Junction
4. Corner
5. Vertex
2. What command creates a surface mesh by selecting 4 edges?
1. EDGE
2. EDGESURF
3. REVSURF
4. TABSURF
5. RULESURF
3. What system variable(s) controls the surface mesh density of the M and N directions when a surface mesh is smoothed with the PEDIT command?
1. SURFMESH
2. SURFTAB1 and SURTAB2
3. SPLFRAME
4. SURFV and SURFU
5. SURFTYPE
4. What type of AutoCAD object is a two-dimensional solid created within a closed object? Choose the BEST answer.
1. Wireframe
2. Mesh
3. Region
4. Surface
5. Solid
5. A mesh is defined by rows and columns. What are the columns called?
1. M
2. S
3. R
4. C
5. N
6. What command creates a mesh from a path curve along a direction vector?
1. 3DMESH
2. EDGE
3. 3DFACE
4. REVSURF
5. TABSURF
7. What system variable(s) controls the mesh density of a surface mesh when the mesh is created?
1. SURFMESH
2. SURFTAB1 and SURTAB2
3. SPLFRAME
4. SURFV and SURFU
5. SURFTYPE
8. What command creates a surface face bounded by a minimum of three and a maximum of four edges?
1. 3DMESH
2. EDGE
3. 3DFACE
4. REVSURF
5. TABSURF
9. What system variable(s) controls the display of splines and meshes that have been smoothed with the PEDIT command?.
1. SURFMESH
2. SURFTAB1 and SURTAB2
3. SPLFRAME
4. SURFV and SURFU
5. SURFTYPE
10. What command creates an irregular complex surface mesh from a grid of XYZ coordinates?
1. 3DMESH
2. EDGE
3. 3DFACE
4. REVSURF
5. TABSURF
Lab Exercise 16-1A OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1A 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the Base. (Figure Step 1)
Step 2
On layer: Surface Base, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 2)
Step 3
Create a block of the model. Name it: AutoCAD 3D Lab 16-1A. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1B OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1B 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the Support. (Figure Step 1)
Step 2
On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.
Step 3
On layer: Surface Support, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)
Step 4
Create a block of the model. Name it:
AutoCAD 3D Lab 16-1B. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1C OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1C 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the Axel. (Figure Step 1)
Step 2
On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.
Step 3
On layer: Surface Axel, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)
Step 4
Create a block of the model. Name it:
AutoCAD 3D Lab 16-1C. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1D OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1D 3D Layout English Inches
Step 1
on layer Model, draw a wireframe model of the Wheel. (Figure Step 1)
Step 2
On layer Construction, add any necessary construction objects that may help insert the model into the assembly.
Step 3
On layer Surface Wheel, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)
Step 4
Create a block of the model. Name it:
AutoCAD 3D Lab 16-1D. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1E OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1E 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the Washer. (Figure Step 1)
Step 2
On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.
Step 3
On layer: Surface Washer, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)
Step 4
Create a block of the model. Name it:
AutoCAD 3D Lab 16-1E. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1F OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1F 3D Layout English Inches
Step 1
On layer: Model, draw a wireframe model of the Bolt. (Figure Step 1)
Step 2
On layer: Construction, add any necessary construction objects that may help to insert the model into the assembly.
Step 3
On layer: Surface Bolt, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)
Step 4
Create a block of the model. Name it:
AutoCAD 3D Lab 16-1F. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 16-1 OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 16-1 3D Layout English Inches
Step 1
Start a new drawing and save it with the name: AutoCAD 3D Lab 16-1.
Step 2
Open the six drawings that were created earlier in this lab exercise.
Step 3
Set the UCS to World and using DesignCenter, insert the following blocks into the drawing: AutoCAD 3D Lab 16-1.
1- AutoCAD 3D Lab 16-1A
2- AutoCAD 3D Lab 16-1B
1- AutoCAD 3D Lab 16-1C
1- AutoCAD 3D Lab 16-1D
4- AutoCAD 3D Lab 16-1E
4- AutoCAD 3D Lab 16-1F
Step 4
Close all drawings except for: AutoCAD 3D Lab 16-1
Step 5
Ensure that layers: Model and Construction are on and all surface layers are off. Move the blocks into their exact location to create the assembly using the model or construction objects and object snap to help locate them accurately.
Step 6
Turn on all surface layers and turn off the layers: Model and Construction. (Figure Step 6)
Step 7
With UCS set to World, copy the complete Caster Assembly 10 inches in the X direction. Rotate the copy of the assembly 180 degrees around the X axis. (Figure Step 7) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/03%3A_Part_3/3.05%3A_Module_16_Competency_Test_No.3_Open_Book.txt |
Module 17: Solid Modeling – Part 1
Learning Outcomes
When you have completed this module, you will be able to:
1. List the six solid primitives.
2. Apply the BOX, WEDGE, CYLINDER, UNION, and SUBTRACT commands to draw solid models using solid models using solid primitives.
Solid Modeling
A solid model is the best possible computerized representation of a real object. A solid model is one AutoCAD object. It is a much more complete model then a wireframe or a surfaced model. A solid model, unlike a hollow wireframe or surfaced model, is solid. A solid model can be rendered or shaded plus the mass properties can be obtained from it. Displaying the mass properties is taught in Module 25.
In a lot of ways, constructing a solid model is simpler than constructing a surfaced model. It is important to understand that when you construct solid models, you must still use all of the 3D construction techniques that were taught in the first 16 modules.
Solid Primitives
The most basic method of constructing solid models is to create a series of solid primitives and then add them together or subtract them from one another to complete the solid model. Using solid primitives is not the best method of solid modeling but at times they can be a very useful modeling tool. The six primitives are the box, wedge, cylinder, sphere, cone and torus. See Figure 17-1. In this module, you will be constructing solid boxes, wedges, and cylinders.
The next four modules teaches many different commands and techniques used to construct solid models. You can pick and choose how and when to use them to construct each model.
AutoCAD Command: BOX
The BOX command is used to create a solid box primitive.
Shortcut: none
AutoCAD Command: WEDGE
The WEDGE command is used to create a solid wedge primitive.
Shortcut: none
AutoCAD Command: ISOLINES
The ISOLINES system variable is used set the number of contour lines that a curved surface solid model will be constructed with. The valid settings are from 0 to 2047. After you change the setting with this variable, the drawing must be regenerated to display the revised setting.
Shortcut: none Command: ISOLINES
Enter new value for ISOLINES <8>: 32
Command:
AutoCAD Command: UNION
The UNION command is used to join two or more solids together to form one solid object.
Shortcut: none
AutoCAD Command: SUBTRACT
The SUBTRACT command is used to subtract one or more solids from another solid.
Shortcut: SU
AutoCAD Command: CYLINDER
The CYLINDER command is used to create a solid cylinder primitive.
Shortcut: none
WORK ALONG: Creating Solid Models Using Boxes, Wedges and Cylinders
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 17-1. (Figure Step 2A and 2B)
Step 3
Set the current view to SE Isometric, the current UCS to World and the current visual style to 2D Wireframe.
Step 4
Set the current layer to Solid 7.
Step 5
Enter the BOX command, as shown below, to draw the solid box. (Figure Step 5).
Command: BOX
Specify first corner or [Center]: 0,0,0 Specify other corner or [Cube/Length]: @6,4
(6 units in the positive X and 4 units in the positive Y.)
Specify height or [2Point] <3.1668>: 1
(1 unit in the positive Z.)
Command:
Step 6
Enter the BOX command, as shown below, to add a box to the model. (Figure Step 6A and 6B).
Command: BOX
Specify first corner or [Center]: (end) P1
Specify other corner or [Cube/Length]: @1,4
Specify height or [2Point] <1.0000>: 3
Command:
Step 7
Using on of the orbit commands, orbit the model slightly. Enter the WEDGE command, as shown below, to create a solid wedge primitive as shown in the figure. Using the MOVE command, move the wedge to centre it. Move the wedge by snapping to the midpoint of the wedge to the midpoint on the box. (Figure Step 7A, 7B, and 7C)
Command: WEDGE
Specify first corner or [Center]: (mid)
(See Figure Step 7A)
Specify other corner or [Cube/Length]: @2,1
Specify height or [2Point] <3.0000>: 2
Command:
Step 8
Draw three construction lines on the edges of the box. (Figure Step 8)
Step 9
Offset the construction lines to locate the centre of the holes. (Figure Step 9)
Step 10
Enter the ISOLINES system variable, as shown below, setting it to 16. Command: ISOLINES
Enter new value for ISOLINES <4>: 16
Command:
Step 11
Enter the CYLINDER command, as shown below, to construct a cylinder for the left hole. After you do that, construct the cylinder on the right side. (Figure Step 11A and 11B)
Command: CYLINDER
Current wire frame density: ISOLINES=16
Specify centre point for base of cylinder or [Elliptical] <0,0,0>: (int) P3
Specify radius for base of cylinder or [Diameter]: D
Specify diameter for base of cylinder: 0.75
Specify height of cylinder or [Center of other end]: -1
(Since the cylinder is constructed 1 unit in the -Z direction -1 is used here.)
Command:
Step 12
Turn layer Construction off and your model should appear as shown in the figure. (Figure Step 12)
Step 13
Enter the UNION command, as shown below, to create one solid from the two boxes and the wedge. (Figure Step 13)
Command: UNION
Select objects: 1 found
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
(Select one solid at a time by picking them.)
Select objects:
Command:
Step 14
Your model is now one solid and should appear as shown in the figure. (Figure Step 14)
Step 15
Enter the SUBTRACT command, as shown below, to subtract the two cylinders from the model to create the holes. (Figure Step 15A and 15B)
Command: SUBTRACT
Select solids and regions to subtract from ..
Select objects: 1 found
(Select the solid model. See Figure Step 15A)
Select objects:
(Press Enter to change to subtract mode.)
Select solids and regions to subtract .. Select objects: 1 found
Select objects: 1 found, 2 total
(Select each cylinder by picking them one at a time See Figure Step 15B.)
Step 16
Open the Properties window and select the solid model. Ensure it is one AutoCAD object only. (Figure Step 16)
Step 17
Set the current visual style to Realistic. (Figure Step 17)
Step 18
Save and close the drawing.
MUST KNOW: When two or more solid primitives are used to construct a solid model, the UNION and/or SUBTRACT commands must be used to create one solid object which is one AutoCAD object. When complete, a solid model must be only one object.
Key Principles
Key Principles in Module 17
1. A solid model is the best possible computerized representation of an object. It is a much more complete model then a wireframe or a surfaced model. A solid model can be rendered or shaded plus the mass properties can be obtained from it.
2. Using solid primitives is not the best method of solid modeling, but at times they can be a very useful modeling tool.
3. Ensure that you disable osnap mode when you are not using When working in 3D, an enabled osnap mode can cause a lot of problems.
4. The ISOLINES system variable is used set the number of contour lines that are used to construct curved surfaces in the solid model.
Lab Exercise 17-1
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 17-1 3D Layout English Inches
Step 1
On layer Solid 3, draw a solid model of the object. (Figure Step 1A, 1B, and 1C)
Step 2
Set the Isolines to 16.
Step 3
Use the UNION and SUBTRACT commands to create one solid object only.
Step 4
Set the current visual style to Realistic and check the model by orbiting it with the with the 3DFORBIT command.
Step 5
Check to ensure that the solid is one object only. See Step 16 in WORKALONG: Creating Solid Models Using Boxes, Wedges and Cylinders.
Step 6
Save and close the drawing.
Lab Exercise 17-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 17-2 3D Layout Metric Millimeters
Step 1
On layer Solid 1, draw a solid model of the object. (Figure Step 1A, 1B, and 1C)
Step 2
Set the Isolines to 20.
Step 3
If necessary, use the UNION and SUBTRACT commands to create one solid object only.
Step 4
Set the current visual style to Realistic and check the model by orbiting it with the with the 3DFORBIT command.
Step 5
Check to ensure that the solid is one object only. See Step 16 in WORKALONG: Creating Solid Models Using Boxes, Wedges and Cylinders.
Step 6
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/04%3A_Part_4/4.01%3A_Module_17-_Solid_Modeling__Part_1.txt |
Module 18 Solid Modeling – Part 2
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how solid models are created by extrusion or revolving.
2. Apply the JOIN command to create a single 2D or 3D object from existing objects.
3. Apply the EXTRUDE, PRESSPULL, and REVOLVE commands to draw solid models.
4. Set the DELOBJ system variable to control objects used to create solid models.
Constructing Solid Models Without Using Solid Primitives
Constructing most solid models using solid primitives would be to difficult and slow. It is much faster and simpler to construct most solid models using the EXTRUDE and/or the REVOLVE commands.
Extruding
Extruding involves drawing a closed object and, using the EXTRUDE or the PUSHPULL command, project it in the Z direction at a given distance. See Figure 18-1. The closed object can be a 2D polygon, a circle or an ellipse. Extruded solids can then be joined with the UNION command or subtracted using the SUBTRACT command to form the final solid model.
Revolving
Not all solid models can be extruded. A solid model that is symmetrical can be created by revolving a closed object. See Figure 18-2. The closed 2D object can be a polygon, a circle or an ellipse. It is then revolved around an axis. The contour of the object will create the solid as it is revolved around the axis. It can be revolved any angle from 1 degree to 360 degrees.
AutoCAD Command: JOIN
The JOIN combines a series of finite linear and open curved objects at their common endpoints to create a single 2D or 3D object.
Shortcut: J
AutoCAD Command: EXTRUDE
The EXTRUDE command is used to create a solid by projecting a closed 2D object along the Z axis of the current UCS.
Shortcut: EXT
AutoCAD Command: DELOBJ
The DELOBJ system variable controls whether the EXTRUDE or REVOLVE command deletes or retains the closed object when the command is executed.
Command: DELOBJ
Enter new value for DELOBJ <0>: Command:
Set to:
0 – Will retain the closed polygon
1 – Will delete the closed polygon
WORK ALONG: Creating a Extruded Solid Model Using the EXTRUDE Command
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 18-1.
Step 3
Set the current visual style to 2D Wireframe, set the layer: Pline as the current layer, the current view to SE Isometric, and the current UCS to World.
Step 4
Draw the top contour of the wireframe model only. Use the multiview drawing as a reference. (Figure Step 4A and 4B)
Step 5
Set the current UCS to Top and locate it at the centre of the circle as shown in the figure. (Figure Step 5)
Step 6
Enter the DELOBJ system variable as shown below. Ensure that it is set to 0. Command: DELOBJ
Enter new value for DELOBJ <1>: 0
Command:
Step 7
Set the system variable ISOLINES to 32, as shown below. Command: ISOLINES
Enter new value for ISOLINES <4>: 32
Command:
Step 8
Enter the JOIN command, as shown below, to create a single 2D polyline from the 8 lines and arcs. (Figure Step 8)
Command: JOIN
Select source object or multiple objects to join at once:
1 found
Select objects to join: 1 found, 2 total
Select objects to join: 1 found, 3 total
Select objects to join: 1 found, 4 total
Select objects to join: 1 found, 5 total
Select objects to join: 1 found, 6 total
Select objects to join: 1 found, 7 total
Select objects to join: 1 found, 8 total
Select objects to join:
8 objects converted to 1 polyline
Command:
Step 9
Click the newly created pline and insure it is closed using the Properties window. (Figure Step 9)
Step 10
Using what you learned in the last two steps join the inside 4 lines and arcs to create on 2D polyline. Check to ensure it is closed using the Properties window. (Figure Step 10)
Step 11
Set layer: Solid 3 as the current layer. Enter the EXTRUDE command, as shown below, to create the solid model.
Command: EXTRUDE
Current wire frame density: ISOLINES=32
Select objects: 6 found
(Select all of the objects in a window or pick then individually.)
Select objects:
Specify height of extrusion or [Path]: -0.75
(Use -0.75 since the extrusion in the negative Z direction.)
Specify angle of taper for extrusion <0>:
(Press Enter to select the default.)
Command:
Step 12
Turn layer: Pline off and your model should appear as shown in the figure. (Figure Step 12)
Step 13
Set the current visual style to Realistic. (Figure Step 13)
Step 14
Set the current visual style to 2D Wireframe. Enter the SUBTRACT command to subtract the five inner solids from the larger solid. (Figure Step 14)
Step 15
Set the current visual style to Realistic. Your model should now appear as shown in the figures. Using the ORBIT command, orbit the model to enure the holes go through the model. (Figure Step 15)
Step 16
Save and close the drawing.
AutoCAD Command: PRESSPULL
The PRESSPULL command is used to create a solid by either selecting an area formed by a closed boundary (or boundaries) or a closed 2D object.
Shortcut: none
WORK ALONG: Creating a Extruded Solid Model Using the PRESSPULL Command
Step 1
Using the NEW command, start a new drawing using template: 3D Layout Metric.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 18-2.
Step 3
Set the current visual style to 3D Wireframe, set layer: Pline, the current view to SE Isometric, and the current UCS to World.
Step 4
Draw the top contour of the wireframe model only. Use the multiview drawing as a reference. (Figure Step 4A and 4B)
Step 5
Use the JOIN command to create a single 2D polyline. Use the Properties window to ensure that the polyline is closed.
Step 6
Set layer: Solid 2 as the current layer.
Step 7
Enter the DELOBJ system variable as shown below and ensure that it is set to 0.
Command: DELOBJ
Enter new value for DELOBJ <1>: 0
Command:
Step 8
Enter the PRESSPULL command. When prompted, select the polyline. Move the cursor in the positive Z direction and the solid will extrude with it. Enter 30 for the height. (Figure Step 8A and 8B)
Command: PRESSPULL
Select object or bounded area:
Specify extrusion height or [Multiple]:
Specify extrusion height or [Multiple]: 30
1 extrusion(s) created
Select object or bounded area:
Command:
Step 9
Using the multiview drawing for the dimensions, draw the lines and arcs in the Front and Right Side of the model. Use the JOIN command to join the plines and ensure that they are closed. (Figure Step 9)
Step 10
Enter the PRESSPULL command and when prompted, select inside the closed pline as shown in the figure. Snap to the back corner to indicate the depth of the extrusion. (Figure Step 10A and 10B)
Step 11
Using the same principle as Step 10, use the PRESSPULL command to extrude the other pline. (Figure Step 11A, 11B, and 11C)
Step 12
Turn layer: Pline off.
Step 13
Your completed model should appear as shown on the figure. (Figure Step 13)
Step 14
Save and close the drawing
AutoCAD Command: REVOLVE
The REVOLVE command is used to create a solid model by revolving a 2D object around an axis.
Shortcut: REV
WORK ALONG: Creating a Revolved Solid Model
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 18-3. (Figure Step 2)
Step 3
Set layer Pline as the current layer and current visual style to 2D Wireframe.
Step 4
Set the current view to SE Isometric and the current UCS to Right. (Figure Step 4)
Step 5
Using the multiview drawing as a reference, draw one-half of the right side cross section of the solid part of the object. (Figure Step 5)
Step 6
On layer: Construction, from 0,0,0 draw a line, of any length, along the X axis. Use ortho mode to draw it quicker. This will be the axis for the revolution and is the centre line of the solid. (Figure Step 6)
Step 7
Using the JOIN command, create a closed polygon from the lines. Ensure that it is closed. (Figure Step 7)
Step 8
Set the ISOLINES system variable to 48 as shown below. Command: ISOLINES
Enter new value for ISOLINES <4>: 48
Command:
Step 9
Set layer Solid 3 as the current layer. Enter the REVOLVE command, as shown below. After completing the command, the model should appear as shown in the figure. (Figure Step 9)
Command: REVOLVE
Current wire frame density: ISOLINES=48
Select objects: 1 found
(Select the closed polyline.)
Select objects:
(Press Enter.)
Specify start point for axis of revolution or define axis by
[Object/X (axis)/Y (axis)]: O
Select an object:
(Select the axis (the construction line.)
Specify angle of revolution <360>:
(Press Enter to select the default.)
Command:
Step 10
Turn off layers: Construction and Pline and set the current visual style to Realistic. (Figure Step 10)
Step 11
Using 3D Orbit, orbit the model as shown in the figure. (Figure Step 11).
Step 12
Save and close the drawing.
Key Principles
Key Principles in Module 18
1. The object being extruded or revolved with the EXTRUDE, PRESSPULL, and REVOLVE commands must be closed polyline, a circle, or an ellipse.
2. Before entering the EXTRUDE command, ensure that UCS is located with the Z axis going in the direction of the extrusion.
Lab Exercise 18-1
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 18-1 3D Layout Metric Millimeters
Step 1
Set the system variable DELOBJ to 0.
Step 2
Draw the closed plines on layer: Pline.
Step 3
On layer: Solid 1, draw a solid model of the object. (Figure Step 3A and 3B)
Step 4
Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.
Step 5
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 7
Save and close the drawing.
Lab Exercise 18-2
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 18-2 3D Layout Metric Millimeters
Step 1
Set the system variable DELOBJ to 0.
Step 2
On layer: Solid 3, draw a solid model of the object. (Figure Step 2A, 2B, 2C, and 2D)
Step 3
On layer: Pline, draw the closed plines.
Step 4
Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.
Step 5
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 7
Save and close the drawing.
Lab Exercise 18-3
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 18-3 3D Layout English Inches
Step 1
Set the system variable DELOBJ to 0.
Step 2
On layer: Solid 4, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)
Step 3
On layer: Pline, draw the closed plines.
Step 4
Use the UNION command to complete the solid model. When complete, the solid must be one object.
Step 5
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 7
Save and close the drawing.
See steps below:
Lab Exercise 18-4
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 18-4 3D Layout Metric Millimeters
Step 1
Set the system variable DELOBJ to 0.
Step 2
On layer: Solid 5, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)
Step 3
On layer: Pline, draw the closed pline.
Step 4
When complete, the solid model must be one object.
Step 5
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 7
Save and close the drawing.
Lab Exercise 18-5
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 18-5 3D Layout English Inches
Step 1
Set the system variable DELOBJ to 0.
Step 2
On layer: Solid 3, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)
Step 3
On layer: Pline, draw the closed plines.
Step 4
Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.
Step 5
Turn layers: Construction and Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 7
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/04%3A_Part_4/4.02%3A_Module_18_Solid_Modeling__Part_2.txt |
Module 19 Solid Modeling – Part 3
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how the UNION, SUBTRACT, and INTERSECT commands are used and applied when solid modeling.
2. Apply the INTERSECT, FILLETEDGE, CHAMFEREDGE, and OFFSETEDGE commands to construct and modify solid models.
Working With Composite Solids
When you are constructing solid models, it is important to ensure that the completed solid model consists of only one object. The three commands used to help you to do this are UNION, SUBTRACT and INTERSECT. Study the following figures to help you understand how these commands affect the solid model.
Figure 19-1 shows two solid models in which parts of each one occupies the same 3D space. This, of course, would be impossible in real life.
Figure 19-2 shows the same model after the UNION command was used to join the two solids into one.
Figure 19-3 shows a shaded model and how the model in Figure 19-1 will appear when the two solids are joined together with the UNION command.
Figure 19-4 shows how the two solids in Figure 19-1 will appear when the cylinder is subtracted from the box using the SUBTRACT command.
Figure 19-5 shows how the two models in Figure 19-1 would appear when the box is subtracted from the cylinder using the SUBTRACT command.
Figure 19-6 shows how the solid models in Figure 19-1 would appear if the INTERSECT command is used. Notice how only the volume shared by the two models remains.
AutoCAD Command: INTERSECT
The INTERSECT command is used to create a solid by finding the volume shared by two or more solids.
Shortcut: none
WORK ALONG: Creating a Solid Model by Intersecting Two or Three Solid Models
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 19-1.
Step 3
Ensure that the DELOBJ system variable is set to 0.
Step 4
Set layer: Pline as the current layer, the current UCS to Front, the current view to SE Isometric, and the current visual style to 2D Wireframe.
Step 5
Set the current UCS to Front. Using the figures as a reference, draw the contour of the Front view. (Figure Step 5A and 5B)
Step 6
Using the JOIN command, create a closed polyline. (Figure Step 6)
Step 7
Set the current UCS to Right and relocate the UCS to the right side as shown in the figure. Using the PLINE command, draw a closed pline of the contour of the right side. (Figure Step 7)
Step 8
Set the current UCS to Top and relocate it to the top corner of the model as shown in the figure. Using the PLINE command, draw a closed pline of the contour of the top view. (Figure Step 8)
Step 9
Set layer: Solid 3 as the current layer. Extrude the Front view the depth of the model. (Figure Step 9)
Step 10
Set the current visual style to Realistic to see the extruded solid. (Figure Step 10)
Step 11
Set the current visual style to 2D Wireframe. Using PRESSPULL, extrude the Right Side and the Top view. Set the current visual style to Realistic to see all three extruded solids at the same time. (Figure Step 11A and 11B)
Save drawing.
Step 13
Set the current visual style to 2D Wireframe. Enter the INTERSECT command, as shown below, to create the common solid from the three intersecting solids. (Figure Step 13)
Command: INTERSECT
Select objects: 1 found
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
(Select each of the solid models.)
Select objects:
Command:
Step 14
Set the current visual style to Realistic. (Figure Step 14)
Step 15
Save and close the drawing.
AutoCAD Command: FILLETEDGE
The FILLETEDGE command is used to create a fillet (tangent arc) on the edge or edges of a solid model.
Shortcut: none
AutoCAD Command: CHAMFEREDGE
The CHAMFEREDGE command is used to create a chamfer on the edge or edges of a solid model.
Shortcut: none
WORK ALONG: Creating Fillets and Chamfers on Solid Models
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 19-2.
Step 3
Set layer: Pline as the current layer, the current UCS to Front, the current view to SE Isometric, and the current visual style to 2D Wireframe. Create a the closed pline on the Front view using the figures as a reference. Ignore the fillets and rounds. (Figure Step 3A, 3B, and 3C)
Step 4
On layer: Solid 2, create a solid model as shown in the figure. Do not include the fillets and rounds. For the hole, extrude a circle. Check to ensure that your model is one solid object only using the Properties window. (Figure Step 4A and 4B)
Step 5
Turn layer: Pline off.
Step 6
Set the current UCS to Top. Copy the solid model, that you completed in Step 4, 8 inches in the positive Y direction. The 8 inches is measured from the same point on model to the same point on the copy. The actual distance between the two model will be 5 inches. (Figure Step 6)
Apply Steps 7 to 10 to the model on the left side of Figure Step 6.
Step 7
Turn layer: Pline off. Enter the FILLETEDGE command, as shown below, to fillet the bottom corners. (Figure Step 7)
Command: FILLETEDGE
Radius = 1.2500
Select an edge or [Chain/Loop/Radius]: P1
Select an edge or [Chain/Loop/Radius]: P2
Select an edge or [Chain/Loop/Radius]:
2 edge(s) selected for fillet.
Press Enter to accept the fillet or [Radius]: R
Specify Radius or [Expression] <1.0000>: 1
Press Enter to accept the fillet or [Radius]:
Command:
Step 8
Enter the FILLETEDGE command, as shown below, to fillet the top edge. (Figure Step 8)
Command: FILLETEDGE
Radius = 1.0000
Select an edge or [Chain/Loop/Radius]: P3
select an edge or [Chain/Loop/Radius]: C
(Use the Chain option.)
Select an edge chain or [Edge/Radius]: E
Select an edge or [Chain/Loop/Radius]: P4
Select an edge or [Chain/Loop/Radius]: P5
Select an edge or [Chain/Loop/Radius]: P6
Select an edge or [Chain/Loop/Radius]: R
Enter fillet radius or [Expression] <1.0000>: .125
Select an edge or [Chain/Loop/Radius]:
4 edge(s) selected for fillet.
Press Enter to accept the fillet or [Radius]:
Command:
Step 9
Enter the FILLETEDGE command, as shown below, to fillet the top of the hole. (Figure Step 9)
Command: FILLETEDGE
Radius = 0.1250
Select an edge or [Chain/Loop/Radius]: P7
Select an edge or [Chain/Loop/Radius]:
1 edge(s) selected for fillet.
Press Enter to accept the fillet or [Radius]:
Command:
Step 10
Set the visual style to Realistic. The drawing should appear as shown in the figure. (Figure Step 10)
Step 11
Referring to the figures, edit the model shown in Steps 11 to 13. (Figure Step 11A and 11B)
Apply Steps 12 to 14 to the model on the right side in Figure Step 6.
Step 12
Enter the CHAMFEREDGE command, as shown below, to chamfer the bottom corner. (Figure Step 12A and 12B)
Command: CHAMFEREDGE
Distance1 = 1.2500, Distance2 = 1.2500
Select an edge or [Loop/Distance]: P1
Select another edge on the same face or [Loop/Distance]: D
Specify Distance1 or [Expression] <1.0000>: 1
Specify Distance2 or [Expression] <1.0000>: 1
Select another edge on the same face or [Loop/Distance]:
Press Enter to accept the chamfer or [Distance]:
Command:
Step 13
Enter the CHAMFEREDGE command, as shown below, to chamfer the hole. (Figure Step 13A and 13B)
Command: CHAMFEREDGE
Distance1 = 1.0000, Distance2 = 1.0000
Select an edge or [Loop/Distance]: P2
Select another edge on the same face or [Loop/Distance]: D
Specify Distance1 or [Expression] <1.0000>: .15
Specify Distance2 or [Expression] <1.0000>: .15
Select another edge on the same face or [Loop/Distance]:
Press Enter to accept the chamfer or [Distance]:
Command:
Step 14
Enter the CHAMFEREDGE command, as shown below, to create a loop chamfer around the top of the model. (Figure Step 14)
Command: CHAMFEREDGE
Distance1 = 0.1500, Distance2 = 0.1500
Select an edge or [Loop/Distance]: L
Select edge of loop or [Edge/Distance]:
Enter an option [Accept/Next] <Accept>: N
Enter an option [Accept/Next] <Accept>:
Select edge of loop or [Edge/Distance]: D
Specify Distance1 or [Expression] <0.1500>: 0.125
Specify Distance2 or [Expression] <0.1500>: 0.125
Select another edge on the same face or [Loop/Distance]:
Press Enter to accept the chamfer or [Distance]:
Command:
Step 15
Set the current UCS to Realistic. The final drawing should appear as shown in the figure. (Figure Step 15)
Step 16
Save and close the drawing.
AutoCAD Command: OFFSETEDGE
The OFFSETEDGE command is used to create a closed polyline that is offset at a specified distance from the edges of a selected planar face on a 3D solid or surface.
Shortcut: none
WORK ALONG: Creating Fillets and Chamfers on Solid Models
Step 1
Open the drawing: AutoCAD 3D Workalong 19-2. Using SAVEAS, save the drawing with the name: AutoCAD 3D Workalong 19-3 (Figure Step 1)
Step 2
Set layer: Pline as the current layer.
Step 3
Using the model on the left, enter the OFFSETEDGE command, as shown below, to create a closed polyline 0.25 inches from the edge. (Figure Step 3A and 3B)
Command: OFFSETEDGE
Corner = Sharp
Select face:
Specify through point or [Distance/Corner]: D
Specify distance <0.1250>: 0.25
Specify point on side to offset:
Select face:
Command:
Step 4
Set layer: Solid 2 as the current layer. Enter the PRESSPULL command. When prompted, select inside the polyline and enter the height of -0.35 as shown below. (Figure Step 4A and 4B)
Command: PRESSPULL
Select object or bounded area: Specify extrusion height or [Multiple]:
Specify extrusion height or [Multiple]: -0.35
1 extrusion(s) created
Select object or bounded area:
Command:
Step 5
Save and close the drawing.
Key Principles
Key Principles in Module 19
1. When constructing solid models, it is important to ensure that the completed solid model consists of one AutoCAD object.
2. The INTERSECT command is used to create a solid by finding the volume shared by two or more solids.
3. It is important to use the Chain option when starting a fillet on a solid model that starts and ends at the same That ensures that all the corners are filleted correctly.
4. It is important to use the Loop option when starting a chamfer on a solid model that starts and ends at the same That ensures that all the corners are chamfered correctly.
Lab Exercise 19-1
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 19-1 3D Layout Metric Millimeters
Step 1
On layer: Solid 3, draw a solid model of the object. (Figure Step 1A, 1B, and 1C)
Step 2
Draw the closed plines on layer: Pline.
Step 3
Use the INTERSECT command and the two extruded solids to create the solid model.
Step 4
Turn layer: Pline off and set the current visual style to Realistic.
Step 5
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 6
Save and close the drawing.
Lab Exercise 19-2
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 19-2 3D Layout Metric Millimeters
Step 1
Draw the closed plines on layer: Pline.
Step 2
On layer: Solid 3, draw a solid model of the object shown in the figures. (Figure Step 2A, 2B, and 2C)
Step 3
Use the INTERSECT command and the two extruded solids to create the solid model.
Step 4
Add the fillets and chamfers to the solid model.
Step 5
Turn layer: Pline off and set the current visual style to Realistic.
Step 6
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 7
Save and close the drawing.
Lab Exercise 19-3
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 19-3 3D Layout English Inches
Step 1
Draw the closed plines on layer Pline.
Step 2
On layer: Solid 3, draw a solid model of the object shown in the figures. (Figure Step 2A, 2B, and 2C)
Step 3
Add the fillets and chamfers to the solid model.
Step 4
Turn layer: Pline off and set the current visual style to Realistic.
Step 5
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 6
Save and close the drawing.
Lab Exercise 19-4
Time allowed: 40 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 19-4 3D Layout English Inches
Step 1
Draw the closed plines on layer: Pline.
Step 2
On layer: Solid 4, draw a solid model of the object shown in the figures. Figure Step 2A, 2B, 2C, and 2D)
Step 3
Turn layer: Pline off and set the current visual style to Realistic.
Step 4
Set the Insertion Units, change the current UCS to World, and check the model with the key.
Step 5
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/04%3A_Part_4/4.03%3A_Module_19_Solid_Modeling__Part_3.txt |
Module 20 Sectioning Solid Models
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the SLICE command to cut solid models into two individual solids.
2. Apply the SECTION command to create 2D cross sectional regions through solid models.
Sectioning
The SLICE and SECTION commands are used to create cross sections from solid models. They can be very useful commands and save you drawing time.
The SLICE command, see Figure 20-1A and 20-1B, cuts a solid model into two individual solids.
The SECTION command, see Figure 20-2, creates a two dimensional region along a selected cutting plane. The region can then be relocated to produce a cross section view in 2D and used as a detail drawing. See Figure 20-3 and 20-4.
AutoCAD Command: SLICE
The SLICE command is used to cut a solid into two individual solids.
Shortcut: none
AutoCAD Command: SECTION
The SECTION command is used to create a two- dimensional region along a specified plane in a solid object.
Shortcut: SEC
WORK ALONG: Sectioning Solid Models
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 20-1.
Step 3
Using the figures as a reference, draw the closed plines on layer: Pline. (Figure Step 3)
Step 4
Draw the solid model on layer: Solid 7. (Figure Step 4)
Step 5
Turn layer: Pline off. Set the current UCS set to World and make a copy of the solid model 12 inches along the X axis. (Figure Step 5)
Step 6
Set the current visual style to 2D Wireframe. On the original solid model, enter the SLICE command, as shown below, to slice it into two parts. (Figure Step 6A and 6B)
Command: SLICE
Select objects: 1 found
(Select the solid model.)
Select objects:
(Press Enter.)
Specify first point on slicing plane by [Object/Zaxis/View/XY/YZ/ZX/3points] <3points>: (mid) P1
Specify second point on plane: (mid) P2
Specify third point on plane: (mid) P3
(Ensure you snap to the midpoint of each edge. If you drew an imaginary line from P1 to P2 to P3 and back to P1, it would form a cutting plane. You will have to orbit the model to do this.)
Specify a point on desired side of the plane or [keep Both sides]: B
(Enter B to retain both sides of the slice.)
Command:
Step 7
Change the current visual style to Realistic. (Figure Step 7)
Step 8
Using the MOVE command, move the right half away from the left half. The distance you move it is not important. (Figure Step 8)
Step 9
Your model should now appear similar to the figure. (Figure Step 9)
Step 10
Set the current visual style to 2D Wireframe and set layer: Hatch as the current layer. Using the copied solid, enter the SECTION command, as shown below, to create a cross section. (Figure Step 10A and 10B)
Command: SECTION
Select objects: 1 found
(Select the solid.)
Select objects:
Specify first point on Section plane by
[Obj/Zaxis/View/XY/YZ/ZX/3points] <3points>: (mid) P4
Specify second point on plane: (mid) P5
Specify third point on plane: (mid) P6
Command:
Step 11
Using the MOVE command move the region, that you just created, outside of the solid. The distance you move it is not important. (Figure Step 11)
Step 12
Explode the region to convert it to lines. On layer: Hatch, add the lines to complete the cross section view as shown the figure. (Figure Step 12)
Step 13
Set the current UCS to Front, the visual style to 2D Wireframe and set layer: Hatch as the current layer. Using the HATCH command, insert the hatch pattern ANS131. (Figure Step 13)
Step 14
Your drawing should now appear similar to the figure. (Figure Step 14)
Step 15
Move the original solid back together using osnap to locate it exactly. Use the UNION command to join the two halves into one solid model. Using the Properties window, check to ensure that you only have one solid object. (Figure Step 15)
Step 16
Set the current UCS to Right and the visual style to 2D Wireframe. (Figure Step 16)
Step 17
Enter the SLICE command, as shown below, to cut the solid through the centre of the hole on the XY plane. (Figure Step 17)
Command: SLICE
Select objects: 1 found
(Select the solid.)
Select objects: Specify first point on slicing plane by
[Object/Zaxis/View/XY/YZ/ZX/3points] <3points>: XY
(The XY plane is selected to be the cutting plane. All that is required now is a point and the slice will occur. It will then slice at this point parallel to the XY plane.)
Specify a point on the XY-plane <0,0,0>: (cen) of P7
(The centre of the circle is the point selected. The solid will be sliced through centre of the circle, parallel to XY plane.)
Specify a point on desired side of the plane or [keep Both sides]: P8
(Only the left side is kept.)
Command:
Step 18
Set the current UCS to World and the current visual style to Realistic. (Figure Step 18)
Step 19
Save and close the drawing.
Key Principles
Key Principles in Module 20
1. The SLICE command cuts a solid model into two individual solids.
2. The SECTION command creates a two dimensional region along a selected cutting plane. The region can then be relocated to produce a cross section view in 2D and used as a detail drawing.
Lab Exercise 20-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 20-1 3D Layout Metric Millimeters
Step 1
Draw the closed plines on layer: Pline.
Step 2
On layer: Solid 3, draw a solid model of the object shown in the figures. (Figure Step 2A and 2B)
Step 3
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 4
On layer: Hatch, using the SECTION command, create a region at the cutting plane A-A. Crosshatch it with ANSI31. (Figure Step 4)
Step 5
Set the current UCS to World, make a copy of the solid model 180 millimeters apart in the X direction. Do not copy the region with the solid.
Step 6
Slice the model into two solids at cutting plane B-B. Move the two solids 30 millimeters apart. (Figure Step 6)
Step 7
Save and close the drawing.
Lab Exercise 20-2
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 20-2 3D Layout Metric Millimeters
Step 1
Draw the closed plines on layer: Pline.
Step 2
On layer: Solid 2, draw a solid model of the object shown in the figures. (Figure Step 2A and 2B)
Step 3
Set the Insertion Units, change the current UCS to World and check the model with the key.
Step 4
On layer: Hatch, create a 2D region section at the cutting plane B-B. Move the region away from the model and hatch it with ANS131. (Figure Step 4)
Step 5
Set the current UCS to World and make a copy of the solid model 400 millimeters from centre to centre in the X direction.
Step 6
Slice the model into two solids at cutting plane A-A. Keep only the back half of the slice. (Figure Step 6)
Step 7
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/04%3A_Part_4/4.04%3A_Module_20_Sectioning_Solid_Models.txt |
Module 21 Competency Test No.4 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a four hour time limit, complete a written exam and the lab exercises without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. Which one of the following best describes the INTERSECT command?
1. It create a solid by finding the volume shared by two or more solids.
2. It create a solid by subtracting one solid from another.
3. It create a solid by joining two or more solids together.
4. It create a solid by subtracting the largest solid from the smallest one.
5. It create a solid by subtracting the smallest solid from the largest one.
2. What command joins two or more solids into one solid object?
1. SUBTRACT
2. EXTRUDE
3. UNION
4. JOIN
5. INTERSECT
3. Which one of the following primitives cannot be created using the REVOLVE command?
1. Cone
2. Cylinder
3. Sphere
4. Torus
5. Box
4. What command creates a solid by revolving a 2D shape around an axis?
1. SUBTRACT
2. EXTRUDE
3. REVOLVE
4. JOIN
5. INTERSECT
5. What system variable is used to set the number of contour lines that will be used when a curved solid is constructed?
1. SOLIDLINES
2. SURTAB1
3. LINEISO
4. ISOLINES
5. SUFTAB2
6. Which direction, on the current UCS, does the EXTRUDE command project the closed object to create a solid model?
1. X
2. Y
3. Either X or Y
4. Z
5. Either X, Y or Z
7. Which one of the following statements is false?
1. A surfaced model is hollow.
2. The mass properties of a solid model can be obtained.
3. A solid model Is the best computerized representation of an object.
4. A solid model is solid.
5. The mass properties of a surfaced model can be obtained.
8. What type of object is created by the SECTION command?
1. Solid
2. Closed polyline
3. Region
4. Hatch
5. Open polyline
9. Which one of the following is not a solid primitive?
1. Wedge
2. Sphere
3. Rectangle
4. Box
5. Cylinder
10. What command removes one solid from another solid?
1. SUBTRACT
2. EXTRUDE
3. REVOLVE
4. JOIN
5. INTERSECT
Lab Exercise 21-1A OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1A 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer: Solid Base, create a solid model of the Base. (Figure Step 2A and 2B)
Step 3
Create a block of the model. Name it:
AutoCAD 3D Lab 21-1A. Pick an appropriate location for 0,0,0. Set 0,0,0 as the insert point for the block. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1B OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1B 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer: Construction, add any necessary construction objects that will help insert the model into the assembly.
Step 3
On layer: Solid Support, create a solid model of the Support. (Figure Step 3A and 3B)
Step 4
Create a block of the model. Name it: AutoCAD 3D Lab 21-1B. Pick an appropriate location for 0,0,0. Set 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1C OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1C 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer: Construction, add any necessary construction objects that will help insert the model into the assembly.
Step 3
On layer: Solid Axle, create a solid model of the Axle. (Figure Step 3A and 3B)
Step 4
Create a block of the model. Name it: AutoCAD 3D Lab 21-1C. Pick an appropriate location for 0,0,0. Set 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1D OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1D 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer: Construction, add any necessary construction objects that will help insert the model into the assembly.
Step 3
On layer: Solid Wheel, create a solid model of the Wheel. (Figure Step 3A and 3B)
Step 4
Create a block of the model. Name it: AutoCAD 3D Lab 21-1D. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1E OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1E 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer Construction, add any necessary construction objects that will help insert the model into the assembly.
Step 3
On layer: Solid Washer, create a solid model of the Washer. (Figure Step 3A and 3B)
Step 4
Create a block of the model. Name it: AutoCAD 3D Lab 21-1E. Pick an appropriate location for 0,0,0. Set 0,0,0 as the insert point for your block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1F OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1F 3D Layout English Inches
Step 1
Draw all plines on layer: Pline.
Step 2
On layer Construction, add any necessary construction objects that will help insert the model into the assembly.
Step 3
On layer: Solid Bolt, create a solid model of the Bolt. (Figure Step 3A and 3B)
Step 4
Create a block of the model. Name it: AutoCAD 3D Lab 21-1F. Pick an appropriate location for 0,0,0. Set 0,0,0 as the insert point for your block. Ensure that the current UCS is located at the World when creating the block.
Lab Exercise 21-1 OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 21-1 3D Layout English Inches
Step 1
Start a new drawing and save it with the name: AutoCAD 3D Lab 21-1.
Step 2
Open the six drawings that you created earlier in this lab exercise.
Step 3
Set the current UCS to World and using DesignCenter insert the following blocks into the drawing.
1- AutoCAD 3D Lab 21-1A
2- AutoCAD 3D Lab 21-1B
1- AutoCAD 3D Lab 21-1C
1- AutoCAD 3D Lab 21-1D
4- AutoCAD 3D Lab 21-1E
4- AutoCAD 3D Lab 21-1F
Step 4
Close all drawings except for: AutoCAD 3D Lab 21-1
Step 5
Ensure that layers: Pline and Construction are on and all solid layers are off. Move the blocks into their exact location to create the assembly using the model or construction objects locate them accurately.
Step 6
Turn on all solid layers and turn off the layers: Pline and Construction.
Step 7
With UCS in World, copy the complete Caster Assembly 10 inches in the X direction. Rotate the copy of the assembly 180 degrees around the X axis into the position it would be installed. (Figure Step 7) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/04%3A_Part_4/4.05%3A_Module_21_Competency_Test_No.4_Open_Book.txt |
Module 27 Editing Solid Models – Part 1
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how solid models are edited including the terms, body, face and edge.
2. Apply the SOLIDEDIT command to edit faces of solid models.
Editing Solid Models
The SOLIDEDIT command is used to edit solid models. This powerful command has many options and is used to do most of the editing of existing solid models. When editing solids, you must be able to identify and select the body, faces and edges of the solid model.
Body
A body is the solid model itself. See Figure 27-1.
Face
A face is the planer or curved 3D surfaces of the solid model. See Figure 27-2.
Edge
An edge is the shared object between two faces or surfaces of the solid. See Figure 27-3. Editing edges will be covered in Module 23.
AutoCAD Command: SOLIDEDIT
The SOLIDEDIT command is used to edit solid objects.
Shortcut: none
WORK ALONG: Using the SOLIDEDIT Command
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save the drawing and name it: AutoCAD 3D Workalong 27-1.
Step 3
Draw the plines on layer: Pline and the solid model on layer: Solid 6.
Step 4
Draw a solid model of the object shown in the figures. (Figure Step 4A and 4B)
Step 5
If you are using toolbars, enable the display of the Solids Editing toolbar. If you are using ribbons, use the Home tab. (Figure Step 5)
Step 6
Set the view to SE Isometric, the current visual style to 3D Wireframe and the UCS in World. (Figure Step 6)
Step 7
Click the Extrude Faces icon and, as shown below, to extrude the face on the right. (Figure Step 7A, 7B, and 7C)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/eXit] <eXit>: E
Select faces or [Undo/Remove]: P1 2 faces found.
(Select the face. Notice it finds 2 faces.)
Select faces or [Undo/Remove/ALL]: R
(Remove one of the faces.)
Remove faces or [Undo/Add/ALL]: P2 2 faces found, 1 removed.
Remove faces or [Undo/Add/ALL]:
Specify height of extrusion or [Path]: 2
(Extrude the face 2 units in the positive direction.)
Specify angle of taper for extrusion <0>:
Solid validation started.
Solid validation completed.
Command:
Step 8
Click the Extrude Faces icon and complete the command, as shown below, to extrude the face to the bottom. (Figure Step 8A and 8B)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/mAterial/Undo/eXit] <eXit>: E
Select faces or [Undo/Remove]: P3 1 face found.
Select faces or [Undo/Remove/ALL]:
Specify height of extrusion or [Path]: -1
Specify angle of taper for extrusion <0>:
Solid validation started.
Solid validation completed.
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/mAterial/Undo/eXit] <eXit>:
Command:
Step 9
Click the Move Faces icon and complete the command shown below to move the face on the top of the model higher. (Figure Step 9A, 9B, 9C, and 9D)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/eXit] <eXit>: M
Select faces or [Undo/Remove]: P5 2 faces found.
Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: 2 faces found, 1 removed.
Remove faces or [Undo/Add/ALL]:
Specify a base point or displacement: 0,0,0
Specify a second point of displacement: @0,0,1
(Move the in the positive Z or up 1 unit.)
Solid validation started. Solid validation completed.
Enter a face editing option
Command:
Step 10
Click the Offset Faces icon and complete the command, as shown below, to offset the face and the hole onthe right side 2 inches longer.(Figure Step 10A, 10B, 10C, and 10D)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/eXit] <eXit>: O
Select faces or [Undo/Remove]: P6 2 faces found.
Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: P7 2 faces found, 1 removed.
Remove faces or [Undo/Add/ALL]: A
(This time a face must be added in.)
Select faces or [Undo/Remove/ALL]: P8 2 faces found. Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: P9 1 face found, 1 removed.
Remove faces or [Undo/Add/ALL]:
Specify the offset distance: 2
(Offset distance is 2 units.)
Solid validation started.
Solid validation completed.
Enter a face editing option
Command:
Step 11
Click the Delete Faces icon and complete the command shown below to delete a the hole in the model. (Figure Step 11A, 11B, and 11C)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit]
<eXit>: F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/ eXit] <eXit>: D
Select faces or [Undo/Remove]: P10 2 faces found.
Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: P11 2 faces found, 1 removed.
(Remove the left face and keep the hole face.)
Remove faces or [Undo/Add/ALL]:
Solid validation started.
Solid validation completed.
Enter a face editing option
Command:
Step 12
Save and close the drawing.
Key Principles
Key Principles in Module 27
1. When editing solids, you must be able to identify and select the body, faces and edges of the solid model.
2. When editing solids, always use the Solids Editing toolbar instead of trying to enter the commands using another method.
3. One of the trickiest parts of using the SOLIDEDIT command is selecting the solid faces or edges that you want to edit.
Lab Exercise 27-1
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 27-1 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 18-5 and save it with the name: AutoCAD 3D Lab 27-1.
Step 2
Using the SOLIDEDIT command only, edit the solid to appear as shown in the figures. (Figure Step 2A, 2B, and 2C)
Lab Exercise 27-2
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 27-2 N/A Inches
Step 1
Open the drawing: AutoCAD 3D Lab 17-1 and save it with the name: AutoCAD 3D Lab 27-2
Step 2
Using the SOLIDEDIT command only, edit the solid to appear as in the figures. (Figure Step 2A, 2B, and 2C) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/05%3A_Part_6/5.01%3A_Module_27_Editing_Solid_Models__Part_1.txt |
Module 28 Editing Solid Models – Part 2
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the SOLIDEDIT and SOLIDCHECK commands to modify solid models.
2. Apply the INTERFERE command to find interferences between two or more solids.
AutoCAD Command: INTERFERE
The INTERFERE command is used to check if two or more solids occupy the same 3D space. If two or more solids occupy the same 3D space, they will interfere with one another which cannot exist in real life.
Shortcut: none
WORK ALONG: Editing Solid Models
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save the drawing and name it: AutoCAD 3D Workalong 28-1.
Step 3
Draw the plines on layer: Pline and the solid model on layer: Solid 6.
Step 4
Draw a solid model of the object shown in the figures. The location of 0,0,0 is the bottom left corner of the front view. The solid model should appear as shown in the figure. (Figure Step 4A and 4B)
Step 5
If you are using toolbars, enable the display of the Solids Editing toolbar. If you are using ribbons, use the Home tab. (Figure Step 5)
Step 6
With the UCS set to Front, draw a circle by snapping to the midpoint of the bottom edge for the centre and one of the bottom corners for the radius. (Figure Step 6)
Step 7
Click the Imprint icon and complete the command, as shown below, to attach the circle to the front face of the solid. (Figure Step 7A, 7B, and 7C).
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: B
Enter a body editing option
[Imprint/seParate solids/Shell/cLean/Check/Undo/eXit] <eXit>: I
Select a 3D solid: P1
(Select the solid model.)
Select an object to imprint: P2
(Select the circle.)
Delete the source object [Yes/No] <N>: Y
(Delete the original circle.)
Select an object to imprint:
Command:
Step 8
Using the Properties window, check to ensure that the arc and the solid are one solid model and not two separate objects.
Step 9
Using what you learned in Module 27, click the Extrude faces icon to extrude the arc 1 inch in the positive Z direction as shown in the command below. (Figure Step 9A and 9B)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>:F
Enter a face editing option
[Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/eXit] <eXit>: E
Select faces or [Undo/Remove]: P3 2 faces found.
Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: 2 faces found, 1 removed.
Remove faces or [Undo/Add/ALL]:
Specify height of extrusion or [Path]: 1
Specify angle of taper for extrusion <0>:
Solid validation started.
Solid validation completed.
Command:
Step 10
Using what you just learned, draw a 4 inch diameter circle locating its centre at the midpoint of the bottom edge. Imprint the circle to the solid to form the arc . Extrude the arc through the solid to create a slotted arc through the solid. (Figure Step 10A and 10B)
Step 11
Click the Check icon and enter the command, as shown below, to check your solid as a valid solid object. (Figure Step 11A and 11B)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: B
Enter a body editing option
[Imprint/seParate solids/Shell/cLean/Check/Undo/eXit] <eXit>: C
Select a 3D solid:
(Select the solid model.)
This object is a valid ShapeManager solid.
(This is a valid solid.)
Enter a body editing option
Command:
Step 12
Save and close the drawing.
WORK ALONG: Finding the Interference Between Two Solids
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save the drawing and name it: AutoCAD 3D Workalong 28-2.
Step 3
Draw the plines on layer: Pline and the solid model on layer: Solid 7.
Step 4
Draw two solid models using the multiview drawing as a reference. Start the bottom left corner of the cube at 0,0,0. (Figure Step 4A and 4B)
Step 5
If you are using toolbars, enable the display of the Solids Editing toolbar. If you are using ribbons, use the Home tab. (Figure Step 5)
Step 6
Using the UNION command, union the two solids to make them one solid model.
Step 7
Using the Properties window, check to ensure that the two 3D Solid objects are now one 3D Solid object. (Figure Step 7)
Step 8
Set layer: Solid 7 as the current layer. Click the Separate icon and enter the command shown below to separate the two solids. (Figure Step 8)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: B
Enter a body editing option
[Imprint/seParate solids/Shell/cLean/Check/Undo/eXit] <eXit>: P
Select a 3D solid:
(Select the solid.)
Enter a body editing option
Command:
Step 9
Using the Properties window, ensure that the two 3D Solid objects were separated as shown in the figure. (Figure Step 9)
Step 10
Set the current visual style to Realistic. Move the cylinder 3 inches towards the box as shown in the figure. (Figure Step 10)
Step 11
Set the current view to SE Isometric and the current visual style to 3D Wireframe. Enter the INTERFERE command, as shown below, to find the interfering solid. (Figure Step 11)
Command: INTERFERE
Select first set of solids:
(Select one solid.)
Select objects: 1 found
Select objects:
(Press Enter)
Select second set of solids:
Select objects: 1 found
(Select the other solid.)
Select objects:
(Press Enter)
Comparing 1 solid against 1 solid.
Interfering solids (first set): 1
(second set): 1
Interfering pairs: 1
Create interference solids? [Yes/No] <N>: Y
(Enter Y.)
Command:
Step 12
Using the MOVE command, move the 3D Solid object created by the INTERFERE command. Where you move it is not important. (Figure Step 12)
Step 13
Use the UNION command the join the two solids to one. (Figure Step 13)
Step 14
Set the current visual style to Realistic. (Figure Step 14)
Step 15
Save and close the drawing.
System Variable: SOLIDCHECK
The SOLIDCHECK system variable toggles the solid validation on and off when a solid model is selected to be edited in the SOLIDEDIT command.
When the SOLIDEDIT command is executed, the current setting of the SOLIDCHECK system variable is displayed as shown below.
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
(SOLIDECHECK=1 solidcheck is enabled)
(SOLIDECHECK=0 solidcheck is disabled)
Key Principles
Key Principles in Module 28
1. The Separate option of the SOLIDEDIT command is used to separate two solids that have been joined together.
2. The INTERFERE command is used to check if two or more solids occupy the same If two or more solids occupy the same space, they will interfere with one another and in real life could not exist. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/05%3A_Part_6/5.02%3A_Module_28_Editing_Solid_Models__Part_2.txt |
Module 29 Shell
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the SOLIDEDIT command and the Shell option to create a hollow cavity, with a specified wall thickness, in a solid model.
Shell
A shell is preformed when material is removed from the interior of a solid model leaving a hollow cavity with a specify wall thickness. This is done using the Shell option in the SOLIDEDIT command. See Figures 29-1, 29-2, and 29-3.
After entering the Shell option, you can specify one or more faces to be removed. That leaves the remaining faces for the shell walls. If no faces are specified for removal, the shell creates a hollow model. The thickness of the shell wall can also specified.
WORK ALONG: Shelling
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save the drawing with the name: AutoCAD 3D Workalong 29-1.
Step 3
On layer: Solid 3, draw the two solid models using the multiview drawing as a reference. Start the bottom left corner of the cube at 0,0,0. (Figure Step 3A and 3B)
Step 4
If you are using toolbars, enable the display of the Solids Editing toolbar. If you are using ribbons, enable the Home Tab. (Figure Step 4A and 4B)
Step 5
Click the Shell option and enter the command shown below. Enter the wall thickness 0.1 inches. Remove the top face only. (Figure Step 5A, 5B, 5C, and 5D)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>:B
Enter a body editing option
[Imprint/seParate solids/Shell/cLean/Check/Undo/eXit] <eXit>: S
Select a 3D solid:
(Select the box.)
Remove faces or [Undo/Add/ALL]: 2 faces found, 2 removed.
(Select the to of the box.)
Remove faces or [Undo/Add/ALL]: A
Select faces or [Undo/Remove/ALL]: 1 faces found.
(Select the side below the top.)
Select faces or [Undo/Remove/ALL]:
Enter the shell offset distance: 0.1
Solid validation started.
Solid validation completed.
Enter a body editing option
Command:
Step 6
Using what you just learned, click the Shell option again but this time, create a pipe with a 0.25 inch wall thickness. You will have to remove both ends of the pipe. See the command below. (Figure Step 6A, 6B, and 6C)
Command: SOLIDEDIT
Solids editing automatic checking: SOLIDCHECK=1
Enter a solids editing option [Face/Edge/Body/Undo/eXit] <eXit>: B
Enter a body editing option
[Imprint/seParate solids/Shell/cLean/Check/Undo/eXit] <eXit>: S
Select a 3D solid:
Remove faces or [Undo/Add/ALL]: 2 faces found, 2 removed.
Remove faces or [Undo/Add/ALL]: A
Select faces or [Undo/Remove/ALL]: 1 face found.
Select faces or [Undo/Remove/ALL]: R
Remove faces or [Undo/Add/ALL]: 2 faces found, 2 removed.
Remove faces or [Undo/Add/ALL]: A
Select faces or [Undo/Remove/ALL]: 1 face found.
Select faces or [Undo/Remove/ALL]:
Enter the shell offset distance: 0.25
Solid validation started.
Solid validation completed.
Enter a body editing option.
Command:
Step 7
Orbit the model to check for completeness. Set the current view to SE Isometric. (Figure Step 7)
Step 8
Save and close the drawing.
Key Principles
Key Principles in Module 29
1. A shell is preformed when material is removed from the interior of a solid model leaving a hollow cavity with a specify wall This is done using the Shell option in the SOLIDEDIT command.
2. The Shell option is one of the trickiest options to The problem most student have is not knowing how to remove and add the faces back in.
Lab Exercise 29-1
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 29-1 N/A Millimeters
Step 1
Open drawing: AutoCAD 3D Lab 24-1. Save and name the drawing with the name: AutoCAD 3D Lab 29-1. (Figure Step 1)
Step 2
Shell the solid model with a wall thickness of 1.0 mm. Remove the top and bottom to create a funnel. (Figure Step 2A and 2B)
Lab Exercise 29-2
Time allowed: 30 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 29-2 N/A Inches
Step 1
Open drawing: AutoCAD 3D Lab 24-2. Save and name the drawing with the name: AutoCAD 3D Lab 29-2. (Figure Step 1)
Step 2
Shell the solid model with a wall thickness of 0.1 inches. Remove the top to create a bottle. (Figure Step 2A and 2B)
Lab Exercise 29-3
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 29-3 3D Layout English Inches
Step 1
Start a new drawing using the template shown above. Save and name it: AutoCAD 3D Lab 29-3.
Step 2
On layer: Solid Wall Plate, draw the solid model shown in the figures. (Figure Step 2A, 2B, and 2C) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/05%3A_Part_6/5.03%3A_Module_29_Shell.txt |
Module 30 Creating 2D Drawings from Solid Models
Learning Outcomes
When you have completed this module, you will be able to:
1. Apply the SOLVIEW, SOLDRAW, and SOLPROF commands to automatically create 2D working multiview drawings, including pictorial views, from solid models.
Creating 2D Drawings from Solid Models
After an object is constructed as a solid 3D model, there are AutoCAD commands and features available to create and dimension a 2D working multiview drawing. Before you go any farther in this module, you must know and understand the following concepts:
1. Creating and modifying AutoCAD layout drawings.
2. Working in paper space.
3. Creating, editing and setting the scale of viewports.
These three concepts are covered in the AutoCAD 2D book.
AutoCAD Command: SOLVIEW
The SOLVIEW command is used to create views and the necessary layers of a 3D solid model.
Shortcut: none
Important: Before you use the SOLVIEW command, ensure that the current visual style is 2D Wireframe and the Hidden linetype is loaded into the drawing.
AutoCAD Command: SOLPROF
The SOLPROF command is used to create a profile of edges of straight and curved surfaces of a solid model as it is viewed from a selected viewpoint.
Shortcut: none
Important: Before you use the SOLPROF command, ensure that the current visual style is 2D Wireframe and the Hidden linetype is loaded into the drawing.
AutoCAD Command: SOLDRAW
The SOLDRAW command is used to convert views created by the SOLVIEW command by projecting the 3D objects onto a 2D plane and changing hidden objects onto the hidden layer.
Shortcut: none
WORK ALONG: Creating 2D Drawings from a Solid Model
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 30-1.
Step 3
Set the current UCS as World, the current view as SE Isometric, and the current visual style to 2D Wireframe.
Step 4
Using the LINETYPE command, ensure that the Hidden linetype is loaded in the current drawing.
Step 5
Set the Insertion Units to inches and insert the block: AutoCAD 3D Workalong 30-1 at 0,0,0.
Step 6
Explode the block and change the layer that the solid model is on to layer: Solid 7. Using the Properties window, check to ensure that the object is a 3D solid. (Figure Step 6)
Step 7
Save the drawing but do not close it.
Step 8
Enable layout: Module Layout D. (Figure Step 8)
MUST KNOW: VERY IMPORTANT Before you use either the SOLVIEW and the SOLPROF commands, ensure that the current visual style is 2D Wireframe and the Hidden linetype is loaded into the current drawing.
Step 9
Enter the SOLVIEW command, as shown below, to create the top view of the model. Name it: Top. (Figure Step 9)
Command: SOLVIEW
Enter an option [Ucs/Ortho/Auxiliary/Section]: U
(Enter U to draw the view from the UCS.)
Enter an option [Named/World/?/Current] <Current>:
(Accept the default Current.)
Enter view scale <1.0000>:
(Accept the scale of 1.)
Specify view center: P1
(Select a location for the centre of the view.)
Specify view centre <specify viewport>:
(Press Enter to accept the location.)
Specify first corner of viewport: P2
Specify opposite corner of viewport: P3
Enter view name: Top
(The view must be named.)
Command:
Step 10
Enter the SOLVIEW command again, but this time create the front view by projecting orthographically from the top view. Name it: Front. When done that way, the two views will be aligned. (Figure Step 10A and 10B)
Command: SOLVIEW
Enter an option [Ucs/Ortho/Auxiliary/Section]: O
Specify side of viewport to project: (mid)
Specify view center: P4
Specify view centre <specify viewport>:
Specify first corner of viewport: P5
Specify opposite corner of viewport: P6
Enter view name: Front
Command:
Step 11
Using what you just learned, create the right side view and name it: Right. (Figure Step 11A and 11B)
Command: SOLVIEW
Enter an option [Ucs/Ortho/Auxiliary/Section]: O
Specify side of viewport to project:(mid)
Specify view center:
Specify view centre <specify viewport>:
Specify first corner of viewport:
Specify opposite corner of viewport:
Enter view name: Right
Enter an option [Ucs/Ortho/Auxiliary/Section]:
Command:
Step 12
Use the MVIEW command to create a viewport in the top right corner of the drawing. Change the scale of the viewport to 1:1 and the current view to SE Isometric. Pan the model in the viewport to centre it. (Figure Step 12)
Step 13
Using the UNITS command, set the length precision to 8 decimal places. Open the Properties window and select all four viewports as shown in the figure. Check to ensure that the scale of all viewports are set to 1:1. Lock their display. (Figure Step 13)
Step 14
Enter the SOLDRAW command, as shown below, to change the multiviews viewports to 2D. (Figure Step 14A and 14B)
Command: SOLDRAW
Select viewports to draw.
Select objects: 1 found
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
(Select the three multiview viewports.)
Select objects:
One solid selected.
One solid selected.
One solid selected.
Command:
Step 15
Change to current space to Model and select the isometric view as the current viewport. Enter the SOLPROF command as shown below. (Figure Step 15A and 15B)
Command: SOLPROF
Select objects: 1 found
(Select the solid model.)
Select objects:
Display hidden profile lines on separate layer? [Yes/No] <Y>:
(Select the default.)
Project profile lines onto a plane? [Yes/No] <Y>:
(Select the default.)
Delete tangential edges? [Yes/No] <Y>:
(Select the default.)
Enter an option
Command:
Step 16
Change the colors of the layers as shown in the figure. (Figure Step 16)
Step 17
Turn Layer: VPORT off and your completed drawing should appear similar to the figure. (Figure Step 17)
Step 18
Save and close the drawing.
Key Principles
Key Principles in Module 30
1. Before you use the SOLVIEW and the SOLPROF commands, ensure that the current visual style is 2D Wireframe and the Hidden linetype is loaded into the current drawing.
Lab Exercise 30-1
Time allowed: 45 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 30-1 3D English Layout Inches
Step 1
Start a new drawing using the template shown above.
Step 2
Draw the plines on layer: Pline and the solid model on layer: Solid 3.
Step 3
Using the figures as a reference, draw the solid model. (Figure Step 3A, 3B, and 3C)
Step 4
Enable layout: Module Layout D and using the command SOLVIEW, create the three multiviews. Set the scale of the viewports to 1.5:1 and lock their display.
Step 5
Use the SOLDRAW command to change the views to 2D.
Step 6
Using the MVIEW command, create two views and set their view to SE Isometric. Scale the viewports to 1:1 and lock their display. Set one of the views to display shaded.
Step 7
Use the SOLPROF command to create the hidden lines in the isometric viewport. (Figure Step 7)
Step 8
Change the color of the layers to Red for object lines and Blue for the hidden lines. (Hint: See Step 16 of WORKALONG: Creating 2D Drawings from a Solid Model)
Step 9
Fill in the titleblock in paper space.
Step 10
Turn layer: VPORT off. (Figure Step 10)
Step 11
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/05%3A_Part_6/5.04%3A_Module_30_Creating_2D_Drawings_from_Solid_Models.txt |
Module 31 Competency Test No.6 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a three hour time limit, complete a written exam and the lab exercises without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. Which three terms, of a 3D Solid, must the user be able to identify and select when using the SOLIDEDIT command?
1. bodies, faces and solids
2. faces, edges and regions
3. bodies, edges and wireframes
4. bodies, faces and edges
5. edges, solids and regions
2. What visual style must be current when the SOLVIEW command is used to create a 2D multiview(s) of a solid model?
1. Realistic
2. 2D Wireframe
3. Hidden
4. 3D Wireframe
5. Any visual style
3. Which one of the following item(s) must be set in the current drawing before the SOLDRAW and SOLPROF commands are used? Select the best answer.
1. The Hidden linetype is loaded.
2. The current visual style is 2D Wireframe.
3. The current visual style is 3D Wireframe.
4. A and B
5. A and C
4. What command is used to find out if two or more solids occupy the same 3D space?
1. SAMESPACE
2. SUBTRACT
3. INTERFERE
4. UNION
5. EXPLODE
5. Which SOLIDEDIT command option is used to divide two non-touching solid models back into individual solid models that have been joined with the UNION command?
1. Separate
2. Extrude
3. Imprint
4. Shell
5. Check
6. Which SOLIDEDIT command option is used to attach a 2D object onto an existing solid model?
1. Imprint
2. Extrude
3. Separate
4. Shell
5. Check
7. What two commands are used to a create 2D viewport(s), complete with hidden lines, of a solid model?
1. SOLVIEW and MSPACE
2. SOLVIEW and SOLDRAW
3. MVIEW and SOLVIEW
4. SOLPROF and MS
5. MVIEW and PSPACE
8. Which SOLIDEDIT command option is used to create a hollow cavity, with a specified wall thickness, in a solid model?
1. Imprint
2. Extrude
3. Separate
4. Shell
5. Check
9. What linetype must be loaded into the current drawing when using the SOLVIEW and SOLPROF commands?
1. hidden
2. center
3. continuous
4. dashed
5. There is no specific linetype that has to be loaded.
10. Which one of the following terms does the SOLIDEDIT command use when it prompts the user to select a solid model?
1. Model
2. Face
3. Body
4. Solid
5. Edge
Lab Exercise 31-1
Time Allowed: 3 Hours
Drawing Name Template Units
AutoCAD 3D Lab 31-1 3D Layout English Inches
Step 1
Start a new drawing using the template shown above. Save the drawing with the name: AutoCAD 3D Lab 31-1.
Step 2
Draw the polylines on layer: Pline.
Step 3
On layer: Solid 1, draw a solid model of the object shown in the figures. (Figure Step 3A and 3B)
Step 4
On layout: Module Layout C, use the SOLVIEW command to create the three viewports of the model.
Step 5
On layer: VPORT, using the MVIEW command to create viewport. Set the view, in the viewport, to SE Isometric and the visual style Realistic.
Step 6
Set the scale of all four viewports to 1.25 and lock their display. (Figure Step 6)
Step 7
Use the SOLDRAW command to change the three multiviews views to 2D views.
Step 8
Set the current space to Paper and fill in the titleblock. (Figure Step 8)
Step 9
On layout: Module Layout D, using the SOLVIEW and SOLDRAW commands, create the three multiviews of the model.
Step 10
On layer: VPORT, using the MVIEW command, create two viewports. Set the visual style to Realistic and orbit them to match the figure the best you can by eye.
Step 11
Set the scale to 2:1 for the multiviews and 1.5:1 for the isometric views. Lock their display.
Step 12
Change the color of the layers so that the object lines are red and the hidden lines are blue. (Hint: See Module 30, WORKALONG: Creating 2D Drawings from a Solid Model, Step 16)
Step 13
Turn layer VPORT off.
Step 14
Set the current space to Paper and fill in the titleblock. (Figure Step 14)
Step 15
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/05%3A_Part_6/5.05%3A_Module_31_Competency_Test_No.6_Open_Book.txt |
Module 22 Sweeping
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the SWEEP command to create solid models by sweeping a closed profile along a path.
Sweeps
Sweeps are created by sweeping (moving) one or more profiles along a selected path. See Figure 22-1 and 22-2. The path can be an open or closed drawing object but must be one object. If the profile is a closed object, the sweep will create a solid. If the profile is an open object, the sweep will create a surface.
Sweeps are used to create models like pipes, tubbing, drain pipes, gasket grooves, and threads.
Objects that can be used for the path are 2D and 3D splines, 2D and 3D polylines, solids, surfaces and mesh edge sub-objects, helices, arcs, circles, ellipses, elliptical arcs and lines.
Objects that can be used for the profile are 2D and 3D splines, 2D polylines, 2D solids, 3D solid face subobjects, arcs, circles, ellipses, elliptical arcs, lines, regions, solids, surface mesh edge sub-objects and traces.
The system variable DELOBJ can be used to automatically delete or keep the original profile and path geometry used in the SWEEP command.
AutoCAD Command: SWEEP
The SWEEP command is used to create a 3D solid or surface model by sweeping a profile along a path.
Shortcut: none
WORK ALONG: Using the SWEEP Command – Part 1
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 22-1. (Figure Step 2A, 2B, and 2C)
Step 3
Ensure that the DELOBJ system variable is set to 0.
Step 4
Change the visual style to 3D Wireframe.
Step 5
Set layer: Path as the current layer, the current view to SE Isometric, and the current UCS to Front.
Step 6
Using Figure Step 2A as a reference, enable Ortho mode, enter the PLINE command, as shown below, to draw a pline on the front UCS. Start the pline at 0,0,0. (Figure Step 6A and 6B)
Command: PLINE
Specify start point: 0,0,0
Current line-width is 0.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: <Ortho on> 6
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 18
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 8
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:
Command:
Step 7
Using the Properties windows, check to ensure that the object is one polyline. (Figure Step 7)
Step 8
Using the FILLET command and the Polyline option, as shown below, fillet the corners with a radius of 2. (Figure Step 8)
Command: FILLET
Current settings: Mode = TRIM, Radius = 0.0000
Select first object or [Undo/Polyline/Radius/Trim/Multiple]: R
Specify fillet radius <0.0000>: 2
Select first object or [Undo/Polyline/Radius/Trim/Multiple]: P
Select 2D polyline:
(Select the polyline.)
2 lines were filleted
Command:
Step 9
Set layer: Profile as the current layer and the current UCS to Right.
Step 10
Using the Figure Step 2C as a reference, draw a closed pline with its centre at the end of the path. The pline is 2 inches square. (Figure Step 10)
Step 11
Using what you learned earlier in the workalong, fillet the four corners of the pline with a radius of 0.25. (Figure Step 11)
Step 12
Using what you learned earlier, use the Properties windows and insure that object is a closed polyline.
Step 13
Offset the pline, towards the inside, at a distance of 0.05 inches. (Figure Step 13A and 13B)
Step 14
Set layer: Solid 4 as the current layer and the current visual style to Realistic.
Step 15
Use the SWEEP command, as shown below, to sweep both profiles along the path in one command. (Figure Step 15A and 15B)
Command: SWEEP
Current wire frame density: ISOLINES=4, Closed profiles creation mode = Solid
Select objects to sweep or [MOde]: 1 found
(Select one profile.)
Select objects to sweep or [MOde]: 1 found, 2 total
(Select the other profile.)
Select objects to sweep or [Mode]:
(Press Enter)
Select sweep path or [Alignment/Base point/Scale/Twist]:
(Select the path.)
Command:
Step 15
Turn layers: Path and Profile off.
Step 16
Using what you learned earlier in the book, use the SUBTRACT command to subtract the inner solid from the outer solid. (Figure Step 16A, 16B, and 16C)
Step 17
Save and close the drawing.
WORK ALONG: Using the SWEEP Command – Part 2
Step 1
Using the NEW command, start a new drawing using template: 3D Layout Metric.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 22-2. (Figure Step 2)
Step 3
Set the current view to SE Isometric, the current UCS to World, the layer: Path as the current layer, and the current visual style to 2D Wireframe.
Step 4
Using Figure Step 2 as a reference, draw a closed pline as shown in the figure. (Figure Step 4)
Step 6
Using what you learned in the first workalong, fillet all of the corners, in one step, with a radius of 10. (Figure Step 6)
Step 7
Offset the closed pline 5 mm towards the inside. (Figure Step 7)
Step 8
Set the system variable ISOLINES to 24.
Step 9
Set layer: Solid 1 as the current layer. Extrude the outer pline 25 mm in the negative Z. (Figure Step 9)
Step 10
Freeze layer: Solid Off. Change the layer of the extruded outer solid that you created in Step 9 to layer: Solid Off.
Step 11
Extrude the inner pline 20 mm in the negative Z. (Figure Step 11)
Step 12
Change the layer of the first solid from layer: Solid Off to layer: Solid 1. Turn layer: Path off. Your drawing should match the figure. (Figure Step 12)
Step 13
Change the visual style to Realistic. (Figure Step 13)
Step 14
Using the SUBTRACT command, subtract the inner solid from the outer solid. (Figure Step 14)
Step 15
Change the layer of the solid on layer: Solid 1 to layer: Solid Off. Turn layer: Path on and set layer: Profile as the current layer. Set the visual style to 2D wireframe. (Figure Step 15)
Step 16
Change the current UCS to Right.
Step 17
Draw a closed pline 2.5 x 2.5 inches. Start it by snapping to endpoint of the inner pline. (Figure Step 17A, 17B, and 17C)
Step 18
Set layer: Solid 1 as the current layer.
Step 19
Using the SWEEP command, sweep the 2.5 inch closed pline using the inner pline as the path. (Figure Step 19)
MUST KNOW: The SWEEP command requires at least one profile and a path. The path can be an open or closed object. The profile must be closed object to create a solid. The path must pierce or touch the profile.
Step 20
Change the layer of the solid on layer: Solid Off to layer: Solid 1. Turn layers: Path and Profile off and change the visual style to Realistic. (Figure Step 20)
Step 21
Using the SUBTRACT command, subtract the solid that was created using the SWEEP command from the original solid. (Figure Step 21)
Step 22
Save and close the drawing.
Key Principles
Key Principles in Module 22
1. Sweeps are created by sweeping (moving) one or more profiles along a selected path. The path can be an open or closed object but must be one object. If the profile is a closed object, the sweep will create a solid. If the profile is an open object, the sweep will create a surface.
Lab Exercise 22-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 22-1 3D Layout English Inches
Step 1
On layer: Profile, draw the profile as a closed pline and on layer: Path, draw the path as a single pline. (Figure Step 1A and 1B)
Step 2
On layer: Solid 6, create the solid using the SWEEP command.
Step 3
Create the slots by first creating one and mirror it to create the opposite slot. Subtract them to complete the object.
Step 4
Save and close the drawing.
Lab Exercise 22-2
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 22-2 3D Layout English Inches
Step 1
On layer: Path, draw the paths as a circles, and on layer: Profile, draw the closed plines. (Figure Step 1A and 1B)
Step 2
On layer: Solid 3, create the original solid.
Step 3
On layer: Solid 3, create the solids that are to be subtracted using the SWEEP command.
Step 4
Subtract the sweep solids from the original solid.
Step 5
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/06%3A_Part_5/6.01%3A_Module_22_Sweeping.txt |
Module 23 Helix
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the HELIX command to create solid models of springs, coils, and threads.
Helix
Coils, springs, and threads are constructed by drawing a profile and then using the SWEEP command, sweeping it along a path that is a helix drawn with the HELIX command. See Figure 23-1. The shape of the coil, spring or thread is controlled by the shape of the profile. See Figure 23-2, 23-3 and 23-4.
The HELIX command is used to construct a helix. A helix is constructed by specifying one or more setting that consist of the base radius, top radius, height, number of turns, turn height or twist direction.
If the same value for both the base radius and the top radius is specified, a cylindrical helix is created. If different values are specified for the top radius and the base radius, a conical helix is created. If a height value of zero is specified, a flat 2D spiral is created.
AutoCAD Command: HELIX
The HELIX command is used to create a helix.
Shortcut: none
Drafting Lesson: Springs and Threads
Study the Figure 23-5, shown below, to learn the terms used when drawing coil, springs and threads. Pitch is an important term that must be understood and is required when drawing a helix using the HELIX command. AutoCAD’s HELIX command uses the term turn height for the pitch.
Figure 23-6 shows four common thread types and their specifications.
WORK ALONG: Creating Coils
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 23-1. (Figure Step 2A and 2B)
Step 3
Set layer: Helix as the current layer, the current view to SE Isometric, the current UCS to Top, and the current visual style to 3D Wireframe.
Step 4
Enter the HELIX command, as shown below, to draw the coil shown in Figure Step 2A. (Figure Step 4)
Command: HELIX
Number of turns = 3.0000 Twist=CCW
Specify centre point of base: 0,0,0
Specify base radius or [Diameter] <0.5000>: @1,0,0
(I used coordinates to ensure that the helix start along the X axis.)
Specify top radius or [Diameter] <1.0000>: 1
(Diameter of the coil is 2 inches.)
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <4.0000>: H
Specify distance between turns <1.000>: 0.5
(The pitch is 0.5 inches.)
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <4.0000>: T
Enter number of turns <3.0000>: 8
(8 turns means that the coil is 4 inches long.)
Command:
Step 5
Change the current UCS to Front and set layer: Profile as the current layer. Draw a 0.25 diameter circle with its centre located at the end of the helix. (Figure Step 5)
Step 6
Set layer: Solid 8 as the current layer.
Step 7
Using what you learned in Module 22, create the coil by entering the SWEEP command. Select the circle as the profile and the helix as the path. (Figure Step 7)
Step 8
Turn layers: Helix and Profile off. Set the current visual style to Realistic. Your completed 3D solid coil should appear as shown in the figure. (Figure Step 8)
Step 9
Save and close the drawing.
WORK ALONG: Creating Square Threads
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 23-2. (Figure Step 2A and 2B)
Step 3
Set layer: Pline as the current layer, the current UCS to Right, the current view to SE Isometric, and the current visual style to 3D Wireframe.
Step 4
Draw a circle, with a diameter of 1 inch. Locate its centre at 0,0,0. (Figure Step 4)
Step 5
Set layer: Solid 8 as the current layer and extrude the circle 5 inches in the negative Z direction. (Figure Step 5)
Step 6
Change the layer of the solid, that you created in Step 5, to layer: Solid Off. Turn off layers: Solid off and Pline. Set layer: Helix as the current layer.
Step 7
Enter the HELIX command, as shown below, to draw a helix for the thread. (Figure Step 7)
Command: HELIX
Number of turns = 3.0000 Twist=CCW
Specify centre point of base: 0,0,0
Specify base radius or [Diameter] <1.0000>: @0,0.5,0
(This starts the helix at the top at the radius of 0.5 inches.)
Specify top radius or [Diameter] <0.5000>:
(Press Enter)
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <1.0000>: T
Enter number of turns <3.0000>: 20
(Since there are 4 turns per inch and the shaft is 5 inches long, there are 20 turns.)
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <1.0000>: A
Specify axis end point: @0,0,-5
(The end of the axis is 5 inches in the negative Z direction.)
Command:
Step 8
Set layer: Profile as the current layer and the current UCS to Front.
Step 9
Using the figures as a reference, draw a closed pline starting at the end of the helix. (Figure Step 9A, 9B, and 9C)
Step 10
Set layer: Solid 8 as the current layer. Using the SWEEP command, create the square thread by sweeping the profile along the helix. (Figure Step 10)
Step 11
Turn layers: Helix and Profile off. Change the solid on layer: Solid Off to layer: Solid 8.
Step 12
Using the UNION command, union the two solids to form one solid model. (Figure Step 12)
Step 13
Turn layer: Pline on and set it as the current layer.
Step 14
Change the current UCS to Right. Draw a 2 Inch diameter circle with its centre located at 0,0,0. (Figure Step 14)
Step 15
Change the current view to Front. (Figure Step 15)
Step 16
Using the MOVE command, move the 2 inch diameter circle 0.125 inches in the negative Z direction. Using the SLICE command, as shown below, slice the solid model using the 2 inch diameter circle as the Object to create a plane at the slice location. (Figure Step 16)
Command: SLICE
Select objects to slice: 1 found
(Select the solid model.)
Select objects to slice:
(Press Enter.)
Specify start point of slicing plane or [planar Object/Surface/Zaxis/View/XY/YZ/ZX/3points]
<3points>: O
Select a circle, ellipse, arc, 2D-spline, 2D-polyline to define the slicing plane:
(Select the circle.)
Specify a point on desired side or [keep Both sides] <Both>:
(Press Enter.)
Command:
Step 17
Delete the end of the solid that you sliced off. (Figure Step 17)
Step 18
Move the circle 4 inches in the negative Z direction. Using what you learned in the last two steps, slice the solid and delete the portion you sliced off. Set the current view to SE Isometric. (Figure Step 18A, 18B, and 18C)
Step 19
Locate the UCS at the centre of the end of the solid thread. Draw a 0.75 inch diameter circle locating the centre at 0,0,0. On layer: Solid 8, extrude the circle 0.5 inches in the positive Z direction. (Figure Step19)
Step 20
On layer: Pline, draw a 1.5 inch diameter circle locating its centre at the end of the extrusion that you created in Step 19. On layer: Solid 8, extrude the circle 1 inch in the positive Z direction. (Figure Step 20A and 20B)
Step 21
Using what you just learned, orbit the model, relocate the UCS and extrude a 1 inch diameter circle 0.5 inches in the negative Z direction. (Figure Step 21A, 21B, and 21C)
Step 22
Chamfer the end of the shaft 0.125 inches at 45 degrees. (Figure Step 22)
Step 23
Fillet the two edges of the head of the bolt using the radius 0.0625.
Step 24
Change the current view to SE Isometric. Using the UNION command, union the four solids to create on solid model. Your completed model should appear as shown in the figure. (Figure Step 24)
Step 25
Save and close the drawing.
WORK ALONG: Using the HELIX Command – Part 3
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 23-3. (Figure Step 2A and 2B)
Step 3
Using what you learned in the last workalong and using Figure Step 2A as a reference, draw the solid model on layer: Solid 8 to match the figure. Ensure that you union the hexagon and cylinder to create one solid model. (Figure Step 3)
Step 4
Using what you learned in the last workalong, on layer: Helix, draw the helix using the figure as a reference. (Figure Step 4A and 4B)
Step 5
Change the layer of the solid that you drew in Step 3 to layer: Solid Off. Turn off layers: Solid off and Pline.
Step 6
Set layer: Construction as the current layer and the current UCS to Front. (Figure Step 6)
Step 7
On layer: Construction, draw the construction lines for the thread profile. (Figure Step 7A and 7B)
Step 8
On layer: Profile, snapping to the ends of the construction lines, draw the thread profile as a closed pline. (Figure Step 8)
Step 9
Turn layer: Construction off. (Figure Step 9A and 9B)
Step 10
Set layer: Solid 8 as the current layer and the current UCS to Top.
Step 11
Using the SWEEP command, sweep the profile using the helix as a path. (Figure Step 11)
Step 12
Turn layers: Helix and Profile off. Change the solid from layer: Solid Off to layer: Solid 8.
Step 13
Using the SUBTRACT command, subtract the solid thread, that you created in the SWEEP command, from the solid model to create the bolt. (Figure Step 13)
Step 14
Using what you learned in the last workalong, on layer: Pline, draw 1.5 diameter circle locating its centre at the centre of the bottom of the bolt. (Figure Step 14)
Step 15
Set the current view to Front. Move the circle 0.0625 inches in the positive Z direction. (Figure Step 15)
Step 16
Slice the bolt and delete the end. (Figure Step 16)
Step 17
Draw a circle at the end of the threaded shaft and extrude it 0.0625 inches. (Figure Step 17)
Step 18
Union the two solids together and chamfer the end of the bolt using the dimensioned drawing as a reference. (Figure Step 18A and 18B)
Step 19
On layer: Solid 8, anywhere in model space, draw the solid model of the nut to match the figure. Do not draw the hole in the centre. (Figure Step 19A and 19B)
Step 20
On layer: Center Line, draw a line on the centerline of the bolt and the nut. The length of the lines is not important. (Figure Step 20)
Step 21
Using the centerlines to snap to, copy the bolt exactly in the centre of the nut. The vertical location is not important as long as the nut is totally in the threaded area. (Figure Step 21)
Step 22
Using the SUBTRACT command, Subtract the bolt from the nut to leave the nut threaded. (Figure Step 22)
Step 23
Using the centerlines, copy the solid models to create an assembly solid model. After you assemble the two parts by snapping to the centerlines, with Ortho enabled, move the nut, by eye, to locate it vertically. Do not union the bolt and nut together. (Figure Step 23A and 23B)
Step 24
Save and close the drawing.
Key Principles
Key Principles in Module 23
1. Coils, springs and threads are constructed by drawing a profile and then using the SWEEP command, sweeping it along a path that is a helix drawn with the HELIX command.
2. A helix is constructed by specifying one or more setting that consist of the base radius, top radius, height, number of turns, turn height or twist direction. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/06%3A_Part_5/6.02%3A_Module_23_Helix.txt |
Module 24 Loft
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the LOFT command to create solid or surface models by blending them between two or more cross sections.
Loft
A loft is a blend or transition solid or surface that connects two or more cross sections. The cross sections, also called profiles, can be the same or different shapes. See Figure 24-1. The cross sections can also be projected along a path.
The most common drawing objects that can be used for the cross sections are 2D and 3D splines, 2D polylines, 2D solids, arcs, circles, ellipses, elliptical arcs, and lines. For a complete list, see the AutoCAD Help files.
The path must be a single open or closed object. The most common objects that can be used for the path are 2D and 3D splines, 2D and 3D polylines, helices, arcs, circles, ellipses, elliptical arcs, and lines. See AutoCAD’s Help.
AutoCAD Command: LOFT
The LOFT command is used to create a solid or surface by blending two or more cross sections with the same or different shapes.
Shortcut: none
WORK ALONG: Using the LOFT Command
Step 1
Using the NEW command, start a new drawing using template: 3D Layout English.
Step 2
Save and name the drawing: AutoCAD 3D Workalong 24-1.
Step 3
Set the current visual style to 3D Wireframe, the current layer to Profile, the current view to SE Isometric, and the current UCS to Right.
Step 4
Using Figure Step 4A as a reference, draw a 12 × 12 inch closed pline. Start the bottom left corner at 0,0,0 as shown in the figure. (Figure Step 4A and 4B)
Step 5
Using the Properties window, ensure that the square is a closed pline.
Step 6
Copy the closed pline 6 inches in the positive Z direction. (Figure Step 6)
Step 7
Draw a 6 inch diameter circle exactly in the centre of the copied square. (Figure Step 7)
Step 8
Move the circle 8 inches in the positive Z direction. (Figure Step 8)
Step 9
Change the current UCS to Front and the set layer: Path as the current layer.
Step 10
Draw a pline 36 inches in the positive X direction and then 24 inches in the negative Y direction. Start it at the centre of the circle. (Figure Step 10)
Step 11
Fillet the pline with a radius of 12 inches. (Figure Step 11)
Step 12
Change the current UCS to Top and the set layer: Profile as current layer.
Step 13
Draw a 6 diameter circle locating its centre at the bottom end of the pline that you just drew. (Figure Step 13)
Step 14
After drawing the necessary construction lines, draw a 3 x 8 closed rectangular pline with its centre located at the end of the pline. (Figure Step 14A and 14B)
Step 15
Move the rectangular pline 10 inches in the negative Z direction. (Figure Step 15)
Step 16
Set the current view to SE Isometric. (Figure Step 16)
Step 17
Ensure that the system variable DELOBJ is set to 0.
Step 18
Set the current layer to Solid 4 and the system variable ISOLINES to 4.
Step 19
Enter the LOFT command, as shown below, and select the two squares for the cross sections. (Figure Step 19)
Command: LOFT
Current wire frame density: ISOLINES=4, Closed profiles creation mode = Solid
Select cross sections in lofting order or [POint/Join multiple edges/MOde]: 1 found
Select cross sections in lofting order or [POint/Join multiple edges/MOde]: 1 found, 2 total
Select cross sections in lofting order or [POint/Join multiple edges/MOde]: 2 cross sections selected
Enter an option [Guides/Path/Cross sections only/Settings] <Cross sections only>:
(Press Enter)
Command:
Step 20
Turn off layer: Solid Off. Change the layer of the solid that you just created in Step 18 to layer: Solid Off. (Figure Step 20)
Step 21
Using the LOFT command, create a loft selecting the square and circle as the cross sections. (Figure Step 21)
Step 22
Change the layer of the solid that you just created in the loft to layer: Solid Off.
Step 23
Enter the LOFT command, as shown below, to draw a loft between two cross sections that follow a path. Select the two circles for the cross sections, and the pline as the path. (Figure Step 23A and 23B)
Command: LOFT
Current wire frame density: ISOLINES=4, Closed profiles creation mode = Solid
Select cross sections in lofting order or [Point/Join multiple edges/MOde]: 1 found
Select cross sections in lofting order or [POint/Join multiple edges/MOde]: 1 found,2 total
Select cross sections in lofting order or [POint/Join multiple edges/MOde]: 2 cross sections selected
Enter an option [Guides/Path/Cross sections only/Settings] <Cross sections only>: P
Select path profile: 1 found
(Select the pline.)
Command:
Step 24
Using what you already learned in the workalong, change the layer of the solid created in Step 23 to layer: Solid off. Create a solid using the loft command between the circle and the rectangle. (Figure Step 24)
Step 25
Turn off layers: Profile and Path.
Step 26
Change the layer of all solids, that are on layer: Solid Off, to layer: Solid 4.
Step 27
Using the UNION command, union all solids to form a single solid. (Figure Step 27)
Step 28
Save and close the drawing.
Key Principles
Key Principles in Module 24
1. A loft, created with the LOFT command, is a blend or transition solid or surface that connects two or more cross sections. The cross sections, sometimes called profiles, can be the same or different shapes. The cross sections can also be projected along a path.
Lab Exercise 24-1
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 24-1 3D Layout Metric Millimeters
Step 1
On layer: Solid 3, draw a solid model of the object shown in the figure by drawing cross sections and then using the LOFT command. (Figure Step 1)
Step 2
Draw the cross sections on layer: Profile.
Step 3
Union the solids to create one single solid model. (Figure Step 3)
Step 4
Save and close the drawing.
Lab Exercise 24-2
Time allowed: 60 minutes.
Drawing Name Template Units
AutoCAD 3D Lab 24-2 3D Layout English Inches
Step 1
On layer: Solid 2, draw a solid model of the object shown in the figure by drawing cross sections and then using the LOFT command. (Figure Step 1)
Step 2
Draw the cross sections on layer: Profile.
Step 3
Draw the text on layer: Text after you create the solid. Use the font: Tohoma. Select the height of your choice.
Step 4
Union the solids together to create one single solid model. (Figure Step 4)
Step 5
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/06%3A_Part_5/6.03%3A_Module_24_Loft.txt |
Module 25 Mass Properties
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the MASSPROP commands to find the mass properties of solid models.
Geometry Lesson: Mass Properties
The mass properties of a solid object are its mass, centre of gravity, centroid, volume, moments of inertia, products of inertia and radii of gyration. Since the mass refers to a solid object, you can only find the mass properties of a solid model. AutoCAD expresses the mass properties in inches. The mass properties include the following:
Mass the quantity of the matter contained in the solid object. This is determined by the density of the material and the volume of the solid. Mass is not dependent on gravity which makes it different but proportional to weight. Mass is used when considering a measure of a solid’s resistance to inertia.
Volume The amount of space occupied by the solid object.
Bounding box The smallest possible box that the object will fit inside. The box is constructed on the XYZ axis.
Centroid Geometrical centre of the object. If the density of the object is uniform, the centroid is the centre of the mass or the centre of gravity.
Moments of Inertia Is the measure of how the mass is distributed around XYZ axis of the current UCS. The values in the moments of inertia are a measure of the objects resistance to angular acceleration and are used when calculating the stress on the object.
Products of Inertia Similar to moments of inertia, the products of inertia measures the objects resistance to the angular acceleration, except it measures it around each 2D Axis (XY YZ XZ).
Radii of Gyration If the object was a uniform solid, with no holes, the radii of gyration would be the radius the moments of inertia would use to perform its calculations around each axis.
Principal Moments of XYZ Direction This is a measure of the maximum moments of inertia around an axis. When they are maximum, the principle moments are zero.
MUST KNOW: Since AutoCAD cannot assign a material to a solid model, the volume and mass of a solid will be identical. This is because AutoCAD assigns the density of 1 to all solids. To calculate the weight of the solid model, do the following:
The formula to calculate mass or weight of the solid is:
mass= volume X density
Following is a list of the density for three common materials. You can find the density of all materials by searching for lists on the internet.
Steel – 0.2836 lb/in3
Copper – 0.3237 lb/in3
Aluminum – 0.0975 lb/in3
For example, the weight of a cubic foot of steel compared to a cubic foot of aluminum:
Steel – 1728 in3 x 0.2836 = 490.06 lbs
Aluminum – 1728 in3 x 0.0975 = 168.48 lbs
Hint: (12″X12″X12″=1728 in3)
Keep in mind that AutoCAD always works in inches.
AutoCAD Command: MASSPROP
The MASSPROP command is used to compute and display the mass properties of a solid model or a region.
Shortcut: none
WORK ALONG: Finding the Mass Properties of Solids and Regions
Step 1
Start a new drawing using the template: 3D Layout English. Save the drawing with the name: AutoCAD 3D Workalong 25-1
Step 2
Using the INSERT command, insert the block: AutoCAD 3D Workalong 25-1 at the coordinates 0,0,0. Explode the block. Do not explode the solids. Change the solid models to layer: Solid 2.
Step 3
Set the current view to SE Isometric, the current UCS to World and the current visual style to Realistic. Your drawing should appear as shown in the figure. (Figure Step 3)
Step 4
Enter the MASSPROP command, as shown below, selecting the solid model on the left side.
Command: MASSPROP
Select objects: 1 found
(Select the solid model on the left.)
Select objects:
SOLIDS
Mass: 19.0166
Volume: 19.0166Creating Solid Models Using Boxes, Wedges and Cylinder
Bounding box: X: 0.0000—– 4.0000
Y: 0.0000—– 3.0000
Z: 0.0000—– 4.0000
Centroid:X: 1.1528
Y: 1.5000
Z: 1.8564
Moments of inertia: X: 159.7292
Y: 147.0995
Z: 101.3495
Products of inertia: XY: 32.8824
YZ: 52.9538
ZX: 35.1506
Radii of gyration: X: 2.8982
Y: 2.7812
Z: 2.3086
Principal moments and X-Y-Z directions about centroid: I: 52.9685 along [0.9625 0.0000 0.2712]
J: 56.2930 along [0.0000 1.0000 0.0000]
K: 31.7293 along [-0.2712 0.0000 0.9625]
Write analysis to a file? [Yes/No] <N>:
(Accept No as the default.)
Command:
Step 5
Enter the MASSPROP command again and select the solid model on the right side.
Command: MASSPROP
Select objects: 1 found
(Select the solid on the right.)
Select objects:
SOLIDS
Mass: 18.8792
Volume: 18.8792
Bounding box: X: 0.0000—– 4.0000
Y: 8.0000—– 11.0000
Z: 0.0000—– 4.0000
Centroid:X: X: 1.1424
Y: 9.5154
Z: 1.8485
Moments of inertia: X: 1824.7216
Y: 144.5649
Z: 1766.8808
Products of inertia: XY: 205.9529
YZ: 331.6084
ZX: 34.1723
Radii of gyration: X: 9.8312
Y: 2.7672
Z: 9.6741
Principal moments and X-Y-Z directions about centroid: I: 52.3639 along [0.9426 0.1825 0.2795]
J: 55.5396 along [-0.1827 0.9828 -0.0257]
K: 31.1772 along [-0.2793 -0.0269 0.9598]
Write analysis to a file? [Yes/No] <N>: Y
(This time enter Y to write the data to a file.)
Command:
Step 6
Entering Y for yes will open the Create Mass and Area Properties File dialogue box. Save the file in the Lab Exercises folder assign it the same name as the drawing. The extension .mpr is automatically added.
Step 7
Start Notepad. (Figure Step 7)
Step 8
In Notepad, open the file: AutoCAD 3D Workalong 25-1.mpr in the folder you saved it in. (Figure Step 8A, 8B, and 8C)
Step 9
In the Notepad window, you can find the centroid as shown below. This is the centre of gravity of the model.
Centroid: X: 1.1424
Y: 9.5154
Z: 1.8485
Step 10
On layer: Construction, insert a point at the centroid of the model using the POINT command as shown below. Change the point style and your model should appear similar to the figure. The shaded model rotated also is displaying a point at the centroid. (Figure Step 10A and 10B)
Command: POINT
Current point modes: PDMODE=34
PDSIZE=0.0000
Specify a point: 1.1424,9.5154,1.8485
Command:
Step 11
Calculate and record the weight of the solid model made out of aluminum and steel. See MUST KNOW in Geometry Lesson: Mass Properties. Check your answers after Step 18.
Steel -_____________ lbs
Aluminum -________ lbs
Step 12
Using what you learned previously, offset a construction line 0.5 units from the far chamfered edge of the model on its right side. (Figure Step 12)
Step 13
Locate the Top UCS at the end of the line (Figure Step 13)
Step 14
Using what you learned in Module 20, use the SECTION command, as shown below, to create a section at the location of the construction line you just drew. (Figure Step 14)
Command: SECTION
Select objects: 1 found
Select objects: Specify first point on Section plane by
[Object/Zaxis/View/XY/YZ/ZX/3points] <3points>: ZX
Specify a point on the ZX-plane <0,0,0>:
Command:
Step 15
Move the region you just created outside of the model. It is not important where you locate it. Shaded and rotated, your model should appear similar to the figure. (Figure Step 15).
Step 16
Using the MASSPROP command, as shown below, find the mass properties of the region.
Command: MASSPROP
Select objects: 1 found
(Select the region.)
Select objects:
REGIONS
Area: 6.4844
Perimeter: 19.8536
Bounding box X: 3.8918 — 7.8918
Y: 0.0000 — 0.0000
Z: -4.0000 — 0.0000
Centroid: X: 5.0834
Y: 0.0000
Z: -2.1397
Write analysis to a file? [Yes/No] <N>: N
Command:
Step 17
Using what you learned earlier in this module, insert a point at the centroid of the region as shown in the figure. (Figure Step 17)
Step 18
Save and close the drawing.
Answers from Step 11
Steel – 5.3541 lbs
Aluminum – 1.8407 lbs
Key Principles
Key Principles in Module 25
1. Mass properties can only be found for solid models and regions.
2. The formula to calculate mass or weight of a solid is: mass= volume X density
3. AutoCAD always works in inches and reports the mass properties in inches regardless of the what units the drawing was constructed in. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/06%3A_Part_5/6.04%3A_Module_25_Mass_Properties.txt |
Module 26 Competency Test No.5 Open Book
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a three hour time limit, complete a written exam and the lab exercise without the aid of a key.
The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.
Multiple Choice Questions
Select the BEST answer.
1. For which AutoCAD objects can Mass Properties be found?
1. Wireframes and Solids
2. Regions and Faces
3. Solids and Regions
4. Regions and Wireframes
5. Edges and Faces
2. What command is used to create a solid model by moving a profile along a selected path?
1. LOFT
2. SHELL
3. HELIX
4. SWEEP
5. MOVEP
3. What formula is used to find the weight of a solid object?
1. inertia x mass + density
2. density x mass
3. volume + density
4. mass x volume
5. volume x density
4. By default, what extension file name will be assigned to the mass properties report generated from the MASSPROP command?
1. .MRP
2. .MAP
3. .TGA
4. .MPR
5. .MPP
5. What system variable setting controls if the original profile and path geometry are kept or deleted after being selecting in the SWEEP command?
1. DBMODE
2. ISOLINES
3. DELOBJ
4. SURFTAB
5. OBJDEL
6. What command is used to create a coil?
1. HELIX
2. SHELL
3. LOFT
4. SWEEP
5. MOVEP
7. What command is used to create a solid by blending two or more cross sections, that are closed objects, of different shapes?
1. SHELL
2. LOFT
3. HELIX
4. SWEEP
5. MOVEP
8. Which one of the following objects cannot be used as a path for the SWEEP command?
1. 2D Polyline
2. Ellipse
3. Circle
4. Trace
5. 3D Polyline
9. Which two of the following commands are most important commands used to create a thread?
1. LOFT and SHELL
2. SHELL and HELIX
3. HELIX and SWEEP
4. SWEEP and LOFT
5. MOVEP and HELIX
10. When creating a thread, which one of the following objects is used as the path in the SWEEP command?
1. Arc
2. Circle
3. Helix
4. 3D Spline
5. 3D Polyline
Lab Exercise 26-1 OPEN BOOK
Drawing Name Template Units
AutoCAD 3D Lab 26-1 3D Layout English Inches
Step 1
Complete the following steps to draw the individual solid models and assemble them. They can be drawn anywhere in model space. (Figure Step 1A and 1B)
Step 2
Set the system variable DELOBJ to 0.
Step 3
For all solid models, draw the profiles on layer: Profile, the paths on layer: Path, the helixes on layer: Helix, the plines on layer: Pline, and the centre lines on layer: Center Line.
Step 4
Draw a solid model of the bolt on layer: Solid 9 using the dimensioned drawings as a reference. Draw a centre line in the model. (Figure Step 4A, 4B, and 4C)
Step 5
Draw a solid model of the nut on layer: Solid 9 using the dimensioned drawing as a reference. Draw a centre line in the model. (Figure Step 5A and 5B)
Step 6
Draw a solid model of the washer on layer: Solid 8 using the dimensioned drawing as a reference. Draw a centre line in the model. (Figure Step 6A and 6B)
Step 7
Draw a solid model of the spring on layer: Solid 8 using the dimensioned drawing as a reference. Draw a centre line in the model. (Figure Step 7A and 7B)
Step 8
Draw a solid model of the lock washer on layer: Solid 4 using the dimensioned drawing as a reference. Draw a centre line in the model. (Figure Step 8A, 8B, and 8C)
Step 9
Using the centerlines as guide, copy the solid models to create an assembly solid model. After you assemble all the parts, by snapping to the centerlines. Change the current view to Right, the current UCS to Right and with Ortho enabled, move the parts ,by eye, to locate them vertically. (Figure Step 9A and 9B)
Step 10
Save and close the drawing. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_AutoCAD_3D_(Baumback)/06%3A_Part_5/6.05%3A_Module_26_Competency_Test_No.5_Open_Book.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe an Inventor project.
2. Create the Inventor project that you will be using to organize and manage the files that you create while completing the Inventor book.
An Inventor Project
An Inventor project is a user named process to logically organize, store, and manage the valid links to the files created for an undertaking. For each project a user created name and a home folder is assigned. Inventor creates a project file that contains the project’s parameters and the paths to the locations of the files in that project. There is no limit to the number of projects that can be created. Inventor assigns a shortcut for each project so that you can easily select the appropriate project when required.
A project should be created so that it has a logical connection between the files in it. For example, if you were designing and drawing an office chair, all the individual parts of that chair, the assembly drawings, the design data, and the 2D working drawings would be stored in a project that you might name ‘ Office Chair ‘.
When a project is created, Inventor automatically creates a project file and saves it in the home folder of the project. A project file is automatically given the extension .ipj and contains the project parameters data as shown in Figure 1-1. This file also specifies the paths to the templates and files in the project. The information, parameters and data contained in the project file can be edited as required.
MUST KNOW: When a project is created, Inventor automatically creates a project file and saves it in the home folder of the project. A project file is automatically given the extension.ipj and contains the data list of the project’s parameters. The extension .ipj is an acronym for Inventor Project.
Inventor Command: PROJECTS
The PROJECTS command is used to create or manage Inventor projects.
Shortcut: None
WORK ALONG: Creating the Project for the Inventor book
Step 1
Start Inventor and enable the Get Started tab. In the ribbon menu, click Projects. This will display the Projects window. (Figure Step 1)
Step 2
Click the New button along the bottom of the dialogue box. The Inventor project wizard window will open. Enable the New Single User Project button and then click Next. (Figure Step 2A and 2B)
Step 3
Name the project: Inventor Course. (Figure Step 3)
Step 4
Set the location for the Project (Workspace) Folder. To do that, click the Browse button (the one with the 3 dots at the right-hand of the Project (Workspace) Folder) window. In the Browse for Folder dialogue box, locate the folder: C:\CAD Courses\Inventor\Lab Exercises. Highlight it by selecting it and click OK. (Figure Step 4A and 4B)
Step 5
You should now see the Project (Workspace) Folder location as follows: C:\CAD Courses\Inventor\Lab Exercises (Figure Step 5)
Step 6
The Project File to be created will automatically be created by Inventor. (Figure Step 6)
Step 7
Check the completed page and ensure it matches the figure. Click the Finish button to complete the project setup. (Figure Step 7)
Step 8
The Project window will show the new project that you just created. Double click Inventor Course in the Projects name column and note how the check mark icon beside the Inventor Course project indicates it is the current project. (Figure Step 8)
Step 9
Down near the bottom, expand Folder Options and click the Templates folder to select it. (Figure Step 9)
Step 10
While the Templates folder is selected, right-click the mouse. In the right-click menu, click Edit. (Figure Step 10)
Step 11
Click the Browse icon. (Figure Step 11)
Step 12
In the Browse For Folder dialogue box, locate and select the Templates folder: C:\CAD Courses\Inventor\Templates (Figure Step 12)
MUST KNOW: The folder location for the templates in the Inventor book should be set to C:\CAD Courses\Inventor\Templates\ in the Inventor Course project.
Step 13
Click OK and the dialogue box will appear similar to the figure. (Figure Step 13)
Step 14
Click Apply and Done to complete the new project.
Exit Inventor.
Step 16
Open Windows Explorer and locate the folder Lab Exercises in the folder list. The file Inventor Course.ipj, that was automatically created by Inventor in this workalong, should appear in the file list. (Figure Step 16)
MUST KNOW: In the Projects window dialogue box, Inventor Course should always be the current project when you are working on all exercises in the Inventor book.
Key Principles
Key Principles in Module 1
1. An Inventor project is designed to logically organize, store, and manage the valid links to the files created for each undertaking. For each project, a name and a home folder must be assigned.
2. A project file is automatically given the extension .ipj and contains the project’s specifications.
3. check mark beside the Inventor Course project means it is the current project. Ensure that this project is always the current project when working on all exercises in the Inventor book. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.01%3A_Module_1_Projects.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe template files, part files, sketches, and 3D solid models.
2. Describe and configure Inventor’s user interface, its menus, and use of the mouse.
3. Apply the NEW, SAVE, and CLOSE commands to create a new part file using a template plus name, save, and close a file.
Inventor’s Graphic Window
When a file is active, Inventor will display the Graphic window. The Graphic window has two different modes, the Sketch mode and the Model mode. The Sketch mode is used to create and edit 2D sketches that are then extruded or revolved to create 3D solid models. The Model mode is used to view, manipulate and modify 3D solid models. You can switch between these two modes to construct or edit and create the solid model. The mode that is currently displayed is called the current mode. The Model mode must be the current mode to save the file.
A 3D Solid Model
A 3D solid model, Figure 2-1, is the best possible computerized representation of a real object. A solid model can be colored or rendered plus the mass properties can be obtained from it. Mass properties are attributes such as volume, weight, surface area, moments of inertia, and centre of gravity. They are taught in Module 20.
An Inventor File
Regardless of the type of files that are created using Inventor, they are called files as compared to files created on a CAD system which are typically called drawings. A file can be a 3D solid model (called a part), an assembly, a presentation, or a drawing created in Inventor and saved in digital format. The four types of files, taught in this book, that Inventor can create and save are part files, assembly files, presentation files, and drawing files.
A Part File
A part file is one 3D solid model. A part file has the file extension .ipt which is an acronym for Inventor ParT. A part file can be used on its own, used to create a working drawing, used as part of an assembly file, or used as part of a presentation file. Assembly and presentation files are taught in Module 21 to Module 26.
Starting a New File
A new file is started using the NEW command. The NEW command forces you to select the template file that will be used to create the new file. Every new Inventor file must be created from an existing template file. The file currently being editing in Inventor is called the current file or sometimes the active file.
Templates
A template file is simply an Inventor file, set with the desired parameters by its creator, named, and saved. As part of the Inventor book there are two distinct sets of templates provided. One set is in english units and the other set is in metric units. The English templates use the base unit of inches and the metric templates use the base unit of millimeters. Template files can also contain modelling objects so that several similar parts can easily be started from a common pre-built unit.
Saving Files
Inventor keeps the current file in RAM memory. If the computer cashes or the power fails while the operator is working on a file, all the work on the file, since the last time it was saved, will be lost. When the file is saved it saves the current file that is in RAM memory onto the disk drive.
Ensure that the current file is saved frequently to avoid losing production time. You should get into the habit of saving the current file every 5 to 10 minutes.
Inventor Command: NEW
The NEW command is used to start a new file.
Inventor Command: SAVE
The SAVE command is used to save the current file from RAM memory onto the disk drive.
Shortcut: CTRL-S
Inventor Command: CLOSE
The CLOSE command is used to close the current file.
Shortcut: None
Inventor’s Menus
Inventor has many different menus that are used by you to give instructions to Inventor while constructing and editing files. The Inventor menus taught in the Inventor book are the Pull-down menu, the Ribbon menu, the Quick Access toolbar, the Browser bar, and the Right-click menu.
Inventor’s Pull-Down Menu
To pull down Inventor’s Pull-down menu, click the File tab. If the pull down menu item has a small solid triangle at the end, it has a flyout menu associated with it. If you move the cursor on the triangle, the flyout menu will display. See Figure 2-2.
Ribbon Menu
The Ribbon menu is used for most of your work in Inventor. See Figure 2-3.
Browser Bar
The Browser bar displays the hierarchical structure of the model or assembly of the current file. It is your most important and most-used tool to create and modify objects within files. The Browser bar will be taught in more detail in future modules. It is normally docked on the left side of the Graphic window. See Figure 2-4.
Right-Click Menu
When the right mouse button is clicked, it displays the Right-click menu. See Figure 2-5. It is sometimes called the Cursor menu since it displays at the current location of the cursor. This menu changes automatically depending on the current command or operation being performed. It usually takes the new user a bit of time to get used to using this menu.
Status Bar
The Status bar is permanently located along the bottom of the Graphic window. It displays the prompts that the current command is issuing, as shown in Figure 2-6, as well as the coordinate locations, as shown in Figure 2-7. These prompts help you understand what information Inventor requires and the cursor location, length, and angle in the current command.
The Graphic Cursor
The Graphic cursor is used to select menu items or objects on the sketch or model. See Figure 2-8.
Dialogue Boxes
Inventor commands use many different dialogue boxes to obtain information to be used by the command or current operation. A typical dialogue box is shown in Figure 2-9.
The Mouse
Inventor is programed to use the three buttons on the mouse as follows:
Left Button: This is the pick button. Use it to pick objects, pick menu items, or select locations on the sketch or model.
Middle Button: The middle button or the wheel is used to zoom and pan around the Graphic window. This will be discussed in detail in Module 3.
Right Button: The right button displays the Right-click menu. See Figure 2-10. The Right-click menu will change depending on the current command or operation being preformed. It is a very helpful menu and should be used as often as possible when working in Inventor.
Inventor Commands
An Inventor command is an instruction from you to Inventor instructing it what operation to perform. Commands can be entered by selecting an item from a Pull-down menu, a Right-click menu, an icon on a Toolbar, an item on the Panel menu, or entering a shortcut on the keyboard. Since there are usually many different ways of entering the same command, you should select the method that works the best for you. There is no right or wrong way to enter a command. You should experiment to find the fastest method to improve your drawing speed and productivity.
Ending the Current Command
When you enter a command, it becomes the current command or sometimes called the active command. Inventor must be instructed to end the current command. There are two methods available to do this. The first is to press the Esc key on the keyboard and the second is click to Done or Cancel on the Right-click menu as shown in Figure 2-10.
Undo and Redo Commands
In the current file, any Inventor command or commands can be undone to reverse any changes that they may have made. To do this, click the Undo icon in the Quick Access toolbar as shown in Figure 2-11. Each click will undo the previous step. If the Undo icon was used to undo a command or a series of commands, it can be reversed by clicking the Redo icon. See Figure 2-12.
WORK ALONG: Creating and Saving a Part File
Step 1
Start Inventor and check the current project. If required, set it to Inventor Course. (Figure Step 1)
Step 2
Click the NEW command icon in the upper left corner of the screen or under the File tab. In the Create New File dialogue box, enable the folder: Templates – English. (Figure Step 2A and 2B)
Step 3
Select the template: Modules Part (in).ipt icon and click OK. (Figure Step 3)
Step 4
Inventor will display the Graphic window, in Sketch mode, as shown in the figure. (Figure Step 4)
Step 5
Click the Finish Sketch icon to change to Model mode. (Figure Step 5A and 5B)
Step 6
Click the Save icon. It will open the Save As dialogue box. In the File name: box, enter the name: Inventor Workalong 02-1 and click Save. (Figure Step 6A and 6B)
Step 7
The file name should now display on top bar of the Graphic window similar to what is shown in the figure. (Figure Step 7)
Step 8
Click the File tab and then the Close icon to close the current part file. (Figure Step 8)
Step 9
Click the Inventor icon to pull down the menu. On the Pull-down menu, click Exit Autodesk Inventor Professional to exit Inventor. (Figure Step 9)
WORK ALONG: Configuring and Working with Inventor’s Interface
Step 1
Start Inventor and check the current project. If required, set it to Inventor Course.
Step 2
Click the New icon. In the New File dialogue box, enable the folder: Metric Templates.
Step 3
Select the template: Module Part (mm).ipt. (Figure Step 3)
Step 4
Click Finish Sketch to exit Sketch mode. While in Model mode, save the part file with the name: Inventor Workalong 02-2. (Figure Step 4)
Step 5
Move the cursor onto the space between the plus (+) sign and the magnifying glass at the top of the Browser bar and press and hold the left mouse button down. While holding the button down, drag the Browser bar into the Graphic window. The Graphic window should appear similar to the figure. (Figure Step 5)
USER TIP: The Status bar displays Inventor prompts to the you. Watch it closely as it will display what information the current command is looking for from you or coordinate information of the current cursor location.
Step 6
Move the cursor onto the space between the plus (+) sign and the magnifying glass at the top of the Browser bar and press and hold the left mouse button down. While holding the button down, drag the Browser bar to the left until its colors fade. Release the left mouse button and the browser bar will dock on the left edge of the screen. (Figure Step 6)
MUST KNOW: Either the Esc key on the keyboard or the Cancel on the Right-click menu must be used to end the current command. You must always let Inventor know when to terminate the current command.
Step 7
Click Sketch1 in the Browser bar to select it and right click the mouse. In the Right-click menu, click Edit Sketch. (Figure Step 7)
Step 8
The Graphic window will change to Sketch mode and should appear similar to the figure. (Figure step 8)
Step 9
Change to Model mode. Save and close the part file.
MUST KNOW: The Browser bar displays the hierarchical structure of the model or assembly of the current file. It is your most important and most-used tool to create and modify files.
MUST KNOW: A part file is one 3D solid model. A part file has the file extension .ipt. The extension .ipt is an acronym for Inventor ParT. Working drawings can be created from the part file or part of an assembly or presentation file.
Key Principles
Key Principles in Module 2
1. When a file is active, Inventor will display the Graphic window. The Graphic window has two different modes, the Sketch mode and the Model mode. They are used to create 3D solid models, called
2. A part file is one 3D solid model. A part file has the file extension .ipt. The file extension .ipt is an acronym for Inventor ParT. Working drawings can be created from the part file or part of an assembly or presentation file.
3. Every new Inventor file must be created from an existing template
4. Inventor keeps the current file in RAM memory. If the computer cashes or the power fails, all the work on the file, since the last time it was saved, will be lost. When the file is saved, Inventor saves what is in RAM memory onto the disk drive. Ensure that the current file is saved frequently to avoid losing production Saving it every 5 to 10 minutes is a good habit to get into.
5. The Browser bar displays current file’s hierarchical
6. The Status bar, located across the bottom of the Graphic window, is a very important part of the operator’s day-to-day work in Inventor.
7. Inventor must be instructed to end the current command. There are two methods available to do this. The first is to press the Esc key on the keyboard and the second is to click Cancel or Done on the right-click menu. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.02%3A_Module_2_Inventors_User_Interface.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how to change the viewing position of the 2D sketch and the 3D model by zooming, panning, and orbiting.
2. Apply the OPEN command to open existing Inventor files.
3. Apply the ZOOM, ORBIT, ZOOM ALL, PAN, and HOME VIEW commands or use the wheel on the mouse to change the viewing position of the 2D sketch and 3D model.
Viewing the 2D Sketch and 3D Model
In Sketch mode, you are viewing and working on a two dimensional plane. In Model mode, you are viewing and working in three dimensions the same way the human eye see real objects. It is essential for you to be able to change the viewing position of the 2D sketch and the 3D model as required. This is done by zooming, panning, and orbiting to change the viewpoint of the 2D sketch and the 3D model.
Zooming
Zooming is the process of changing the viewable size of the sketch or model to make it appear either smaller or larger. It is an important tool for you and is used extensively in the drawing and modeling process. As it is zoomed, the size of the sketch or model not changed, Inventor is simply adjusting the distance the object is from your eyes making it appear larger or smaller. I wondered why the Frisbee was getting bigger, and then it struck me…
Panning
Panning is the process of moving the sketch or model around the Graphic window without actually physically moving it from its location in space. It is an important tool for you and is used extensively while working in Inventor.
Orbiting
Orbiting is the process of changing the orientation of the sketch or model in relation to your eyes. Rather then changing the orientation of your eyes, Inventor orbits the sketch or model and your eyes remain stationary. The model and sketch are not physically rotated or their orientation in space changed. Orbiting is used extensively when working in Inventor.
Home View
The Home view is important to you while working in Inventor. It is the viewing position of the sketch or model to a known isometric view. This view re-establishes your bearings to better visualize the sketch or model because you are viewing it in a known viewing position.
Inventor Command: OPEN
The OPEN button under the Get Started tab command is used to open an existing Inventor file.
Shortcut: CTRL+O
Inventor Command: ZOOM
The ZOOM command is used to zoom the sketch or model.
Shortcut: F3
Inventor Command: ZOOM ALL
The ZOOM ALL command is used display the current sketch or model to fit inside the Graphic window.
Shortcut: HOME
Inventor Command: ORBIT
The ORBIT command is used to orbit the sketch or model around the X, Y, or Z axes. The sketch or model can be orbited while another command is active.
Shortcut: F4
Inventor Command:PAN
The PAN command is used to move the sketch or model in the Graphic window.
Shortcut: F2
Inventor Command: HOME VIEW
The HOME VIEW command is used to display the sketch or model in the home view.
Shortcut: F6
WORK ALONG: Viewing the Model
Step 1
Start Inventor and check the current project. If required, set it to Inventor Course.
Step 2
Click the Open icon. In the Open dialogue box, select the file:
Inventor Workalong 03-1.ipt . Note how the file name will appear in the File name: box as shown in the figure. (Figure Step 2)
Step 3
If you are asked to convert the appearance, click Yes. (Figure Step 3).
Step 4
The part will open and display in Model mode and appear similar to the figure. (Figure Step 4).
Step 5
Move the cursor to approximately the centre of the solid model as shown in the figure. While keeping the cursor in the centre, rotate the mouse wheel back and forth. Note how the model appears larger and smaller. (Figure Step 5A and 5B)
USER TIP: When opening a file in Inventor, ensure that the Open File dialogue box is listing the correct file type(s). To list part files which have the extension .ipt , ensure that *.ipt file type is listed in the File of type: box as shown below. The * means that all files that have the extension .ipt.
Step 6
Move the cursor near the model and press and hold the wheel down. A small Hand icon will replace the arrow cursor as shown in the figures. While the Hand icon is displayed, move the mouse to pan the model as shown. (Figure Step 6A, 6B, and 6C)
MUST KNOW: The HOME VIEW command (F6) is a very important command. It is used to change the viewing position of the 2D sketch or 3D model to a known isometric view. By doing this, it re-establishes your bearings to a known viewing position.
Step 7
Press F6 to return the model to its Home view. (Figure Step 7)
Step 8
Press F4 and hold it down. While holding it down, move the cursor outside the orbit circle, as shown below. The cursor will change as shown in the figures. Press and hold down the left mouse button. While holding it down, move the mouse and the model will orbit. (Figures 8A, 8B, and 8C)
Step 9
Press F4 and hold it down. While holding it down, move the Graphic cursor somewhere inside the orbit circle. The icon will change in appearance as shown in the figures. Press the left mouse button and while holding it down, move the mouse. The model will orbit. (Figure Step 9A, 9B, and 9C)
USER TIP: Many Inventor commands have shortcut keys to speed the drawing process. For example, the F4 is the shortcut for the ORBIT command. Using shortcuts are faster than using a menu. It is best to learn and use the shortcuts whenever possible to shorten the drawing time. Inventor shortcuts are shown in the Inventor book and on tooltips in the Inventor menus.
Step 10
Press F6 to return the model to its home view. (Figure Step 10)
Step 11
Close the part without saving it.
USER TIP: While it is not absolutely necessary, it is very helpful to have a mouse with a wheel as the middle button. Rather then using the ZOOM and PAN commands, you can zoom and pan the sketch or model using the wheel. Using the wheel rather then the commands to zoom and pan, will greatly improve your drawing productivity.
Key Principles
The Key Principles in Module 3
1. It is essential for you to be able to change the viewing position of the 2D sketch and 3D This is done by zooming, panning, and orbiting to change viewpoint of the sketch or model.
2. The HOME VIEW command is a very important command. Use it to change the viewing position of the 2D sketch or 3D model to a known isometric view. You can re-establish your bearings to better visualize the sketch or model.
3. Use shortcut keys whenever possible to speed your production. Shortcut keys taught in this module are Home – Zoom All, F2 – Pan, F3 – Zoom, F4 – Orbit, and F6 – Home View. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.03%3A_Module_3_Viewing_the_2D_Sketch_and_3D_Model.txt |
Wally Baumback
idLearning Outcomes
When you have completed this module, you will be able to:
1. Describe the Cartesian Coordinate System, parametric solid modeling, the Base sketch, and geometrical constraints.
2. Describe snapping onto grids, lines, endpoints, and midpoints.
3. Describe and apply the PROJECT GEOMETRY command to project the Center Point onto the Base sketch.
4. Following Inventors 2D sketching rules, describe and apply the LINE command to draw the Base sketch of simple solid models.
Geometry Lesson: Points and Lines
A point is defined as a single XY coordinate. It does not have width, height, or depth. A line is the shortest distance between two XY coordinates. Lines can be horizontal, vertical, or inclined. Lines that are the same distance apart are called parallel lines. Perpendicular lines are at right angles to each other or 90 degrees apart. See Figure 4-1 and 4-2.
The Cartesian Coordinate System
To accurately draw two dimensional (2D) Base sketches, you must understand the Cartesian Coordinate System.
The Cartesian Coordinate System consists of two numbered lines crossing perpendicular to one another at their zero values. The horizontal axis is the X axis and the vertical axis is the Y axis. See Figure 4-3. A coordinate value is assigned to each location on the current construction plane. Each coordinate value consists of a pair of numbers, the first is the X coordinate and the second is the Y coordinate, written X,Y. The X and Y values are separated by a comma. For example, X2,Y4 is the location 2 units to the right and 4 units up from X0,Y0 or 0,0.
The values can be either positive or negative. Positive numbers are default so the plus sign is not required. If the value is negative, the minus sign must precede the number. For example, -3,5 is X minus 3 and Y positive 5.
Parametric Solid Modeling
Inventor is a true Three Dimensional Parametric Solid Modeling system. A parametric solid model is a 3 dimensional solid model designed with geometrical and dimensional constraints rather then hard dimensions. A model designed in this way can then be modified by changing the dimensions, and/or constraints during or after the design is complete. When one or more constraints are modified, all other dependant constraints will automatically modify the model to conform to the new constraints. Geometric constraints are taught in this modules and dimensional constraints are taught in Module 5.
Geometrical Constraints
Geometrical constraints are used to apply geometrical relationships to the objects in the 2D sketch. They specify the geometrical relationship that the objects have to the sketching plane and to one another. Relationships like horizontal, vertical, parallel, or perpendicular are used. By applying geometrical constraints the number of dimensional constraints required to fully constrain the model is reduced. Applying the correct geometrical constraints prevents unwanted changes to a feature when geometry or dimensions are modified.
Since the geometrical constraint symbol displays and the constraints are automatically applied as the sketch is drawn, you have control on which constraints are applied to the objects as you are drawing the sketch. Constraints can be added while creating the sketch or by editing the sketch after the solid model is constructed. The geometrical constraints taught in this module are shown in Figure 4-4. Additional geometrical constraints will be taught throughout the Inventor book.
USER TIP: If you draw an incorrect line, you can click the Undo icon to remove it and insert it again. See Module 2, Undo and Redo Commands. It is sometimes easier to undo rather than deleting the line. This will only work if you click Undo icon immediately after you inserted the line and have not exited the LINE command.
Projecting Reference Geometry
Projected reference geometry is geometry that has its position fixed relative to the sketching plane it resides on. Objects in the sketch are constrained with geometrical or dimensional constraints to the reference geometry to constrain it to the sketching plane. If the objects in the sketch are not constrained to the sketching plane, they will free float. A sketch that is not constrained to the sketching plane can never be fully constrained.
Inventor allows reference geometry to be projected in many different methods and uses. Many of these methods will be covered in the Inventor book. In this module, projecting the Center Point onto the plane of the Base sketch is taught.
Snapping
It is absolutely imperative that, when required, you snap to grids or locations on objects when drawing 2D sketches. Snapping to these locations ensures that the sketch is drawn accurately and constrained correctly. Inventor has many different snapping locations and they will be taught throughout the Inventor book. For now, the snap locations shown in Figure 4-5 should be used when drawing sketches. Study the figure before starting the workalong.
Inventor Command: PROJECT GEOMETRY
The PROJECT GEOMETRY command is used to project geometry to a fixed position on the 2D sketch plane.
Shortcut: none
Inventor Command: LINE
The LINE command is used to draw lines on a sketch.
Shortcut: L
Inventor Command: LOOK AT
The LOOK AT command is used to change the users viewpoint to view the model or sketch perpendicular to the selected object, edge, or plane.
Shortcut: PAGE UP
Lines
Lines are the drawing objects that are used the most when drawing 2D sketches. A line is defined as the shortest distance between two XY coordinate locations. Once a line is drawn, Inventor knows the location of its endpoints as well as the midpoint of the line. Other lines or drawing objects can be drawn by snapping to those locations. See Figure 4-6.
Base Sketch
The Base sketch is the first 2D sketch drawn in a new part. After the Base sketch is complete, it is extruded or revolved to create the Base model. Before drawing the Base sketch, you should study the model being constructed to determine the best plane to draw it on. The best view to use is the view with the most complex contour shape that does not contain arcs and curves. Draw the lines using lengths close to the finished dimensions. They do not have to be 100% accurate in length. The following rules should be followed when drawing the base sketch.
1. The objects in the sketch must meet exactly at their endpoints and cannot overlap.
2. The objects must form a perfect closed polygon and cannot contain any gaps.
3. The objects must have geometrical constraints applied to control the shape of the sketch.
4. Leave fillets and chamfers out of the original sketch. They can be added to the model after it is created. This is taught in Module 15.
X0Y0Z0
The two bold grid lines on the sketching plane represents the X and Y axis of the Cartesian Coordinate System. The axis lines display can be either enabled or disabled. It should currently be enabled. The horizontal line is the X axis and the vertical line is the Y axis. The point where they intersect is X0Y0Z0 of the sketch. Z is always zero since it is a 2D sketch.
The location of X0Y0Z0 on the Base sketch is a very important. You should pick its location on sketch carefully since it dictates the location of X0Y0Z0 on the completed model. See Figure 4-7.
The Coordinate System Indicator shows the X, Y, and Z axis. The arrows always point in the positive X, Y, and Z direction. The red arrow is the X axis , the green arrow is the Y axis, the blue arrow is the z axis. See Figure 4-8 and 4-9.
MUST KNOW: Inventor allows files to be created in the units of inches, feet, millimeters, centimeters, meters, and microns. In the Inventor book, the units that are used are either inches or millimeters. When you start a new file, the template file you select sets the default units for that file.
WORK ALONG: Drawing the Base Sketch
Step 1
Start Inventor. Ensure that the current project is Inventor Course.
Step 2
Click the NEW command and start a new part using the template: English-Modules Part (in).ipt.
Step 3
Change to Model mode by clicking in the Finish sketch icon.
Step 4
Save the part file with the name: Inventor Workalong 04-1. The Graphic window should appear similar to the figure. (Figure Step 4)
Step 5
Change to Sketch mode by right clicking Sketch1 in the Browser bar and click Edit Sketch. (Figure Step 5A and 5B)
Step 6
The 3D model that you are constructing in this workalong is shown in the figure. (Figure Step 6A)
Step 7
Press F6 to change to the Home view. (Figure Step 7)
Step 8
Click the PROJECT GEOMETRY command. Note the Status bar, it displays the command prompt. Expand the Origin folder in the Browser bar and click Center Point. Press Esc to end the command and note that after you do that, the Status bar displays the Ready prompt. That means there is no current command. (Figure Step 8A, 8B, 8C, and 8D)
Step 9
Click the LOOK AT command. Move the cursor onto the Browser bar and click the XY Plane. The Graphic window will change to display the top view. Press Esc to end the command. (Figure Step 9A, 9B, and 9C)
Step 10
Press F8. It enables the display of the geometrical constraint icons. To this point, there is only one geometrical constraint applied to sketch. It is the Reference constrain that was applied when you projected the Center Point using the PROJECT GEOMETRY command in Step 8. (Figure Step 10)
Step 11
Press F9 to disable the display of the geometrical constraint icons.
Step 12
Move the cursor somewhere in the Graphic window and right click the mouse. In the Right-click menu, ensure that Snap to Grid is enabled. (Figure Step 12)
Step 13
Click the LINE command. Note the Status bar prompt. Move the cursor to X0Y0Z0 and hold it there. A green snap point will display. That means it is snapping to the Center Point geometry that was projected in Step 8. While the green snap point is displayed, click the left mouse button. (Figure Step 13A, 13B, and 13C)
Step 14
Move the cursor about 4 inches along the positive X axis. Watch the Status bar and it will display the length of the line as the cursor is moved. When it is about 4 inches long and the Horizontal geometrical constraint symbol and the yellow snap point displays, click the left mouse button. (Figure Step 14A and 14B)
Step 15
Move the cursor about 2 inches in the positive Y direction. When the Perpendicular geometrical constraint symbol displays at the same time as the yellow grid snap point, click the left mouse button. (Figure Step 15A and 15B)
Step 16
Move the cursor about 2 inches in the negative X direction. When the Perpendicular constraint symbol displays and the yellow snap grid point displays, click the left mouse button. (Figure Step 16A and 16B)
Step 17
Move the cursor about 2 inches in the positive Y direction. When the Parallel constraint symbol and the yellow snap grid point displays, click the left mouse button. (Figure Step 17A and 17B)
Step 18
Move the cursor about 2 inches in the positive X direction. When the Perpendicular constraint symbol and the yellow snap grid point displays, click the left mouse button. (Figure Step 18A and 18B)
Step 19
Move the cursor about 2 inches in the positive Y direction. When the Perpendicular constraint symbol and the yellow snap grid point displays, click the left mouse button. (Figure Step 19)
Step 20
Move the cursor about 4 inches in the negative X direction. When the Perpendicular constraint symbol and the yellow snap grid point displays, on the Y axis, click the left mouse button. (Figure Step 20)
Step 21
Move the cursor to X0Y0Z0. When the green snap point and the Perpendicular constraint symbol displays, click the left mouse button. (Figure Step 21)
Step 22
Press Esc to end the LINE command. Note that the Status bar prompts Ready meaning there is no current command. (Figure Step 22)
MUST KNOW: When the Snap to Grid feature is enabled, the points selected will snap to locations on the grid. As a beginner, it is best to draw by snapping to the grid to control the location and size of the sketch.
Step 23
Click the LOOK AT command and change the view to the top or XY plane. If you have trouble, see Step 9.
Step 24
Press F8 to display the geometrical constraint icons. They should appear similar to the figure. (Figure Step 24)
MUST KNOW: A correctly drawn Base sketch must form a closed polygon. There can be no gaps. Each object in the sketch must meet exactly at their endpoints and cannot overlap.
Step 25
Move the cursor onto the Horizontal geometrical constraint icon. Note how the bottom line display red to indicate that the constraint is applied to that line. (Figure Step 25)
Step 26
Move the cursor onto a Parallel geometrical constraint icon and note how another Parallel geometrical constraint icon will highlight showing you which two icons match one another. Note how the two parallel lines will also highlight to indicate that the upper line is constrained to the lower line with a Parallel geometric constraint. (Figure Step 26)
Step 27
Move the cursor onto the Perpendicular geometrical constraint icon. Note how the two lines highlight. The vertical line is constrained perpendicular to the horizontal line. (Figure Step 27)
Step 28
Move the cursor onto the small square icon at the bottom right corner of the object. Note how two Coincident geometrical constraint icons will display indicating both line’s endpoints are at the exact same XY location. (Figure Step 28)
Step 29
Press F9 to disable the display of the geometrical constraint icons. Press F6 to display the Home view. The completed sketch should appear as shown in the figure. (Figure Step 29)
Step 30
Return to Model mode.
Step 31
Save and close the file.
Deleting Lines
There are two methods to delete any unwanted drawing object.
Method 1
Ensure that there is no active command and without entering a command, select the drawing object with the cursor. If it is successfully selected, it will change colour. Right click the mouse. In the Right-click menu, click Delete as shown in Figure 4-9.
Method 2
Select the drawing object the same way as in Method 1. When the selected object changes colour, press the Delete key on the keyboard.
Key Principles
Key Principles in Module 4
1. Inventor is a true Three Dimensional Parametric Solid Modeling system. A parametric solid model is a 3 dimensional solid model designed with parameters and constraints rather then hard dimensions.
2. Geometrical constraints are used to apply geometrical relationships on or between the objects in the 2D sketch. They specify the geometrical relationship the objects have to the sketching plane or one another.
3. It is absolutely imperative that, when required, you snap to grids or pre-defined locations on objects when drawing 2D sketches. Snapping ensures that the sketch is drawn accurately and constrained correctly.
4. The Base sketch is the first sketch drawn. The Base sketch is extruded or revolved to create the Base model. Before drawing the Base sketch, you should select the view with the most complex contour shape to draw the sketch on.
5. Projected geometry is geometry that has its position fixed relative to the sketching plane where it originates. Drawing objects in the sketch are constrained or dimensioned to the projected geometry to constrain it to the sketching plane.
Lab Exercise 4-1
Time allowed: 40 minutes.
Part Name Project Units Template Color Material
Inventor Lab 04-1 Inventor Course Inches English-Modules Part (in).ipt N/A N/A
Step 1
Start a new part file with the template: English – Modules Part(in).ipt save the file with the name: Inventor Lab 04-1 as shown above.
Step 2
Project the Center Point onto the Base sketch.
Step 3
Draw the Base sketch for the 3D model shown below and apply all of the necessary geometrical constraints. Note the location of X0Y0Z0. (Figure Step 3A and 3B)
Lab Exercise 4-2
Time allowed: 40 minutes.
Part Name Project Units Template Color Material
Inventor Lab 04-2 Inventor Course Inches English-Modules Part (in).ipt N/A N/A
Step 1
Start a new part file with the template: English – Modules Part(in).ipt and save the file with the name: Inventor Lab 04-2 as shown above.
Step 2
Project the Center Point onto the Base sketch.
Step 3
Draw the Base sketch for the 3D model shown below and apply all of the necessary geometrical constraints. Note the location of X0Y0Z0. (Figure Step 3A and 3B) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.04%3A_Module_4_Sketching_Lines.txt |
Wally Baumback
Learning Outcomes
When you have completed this module you will be able to:
1. Describe dimensional constraints, linear dimensions, driving and driven dimensions.
2. Apply the GENERAL DIMENSION command to insert the necessary linear dimensions to fully constrain Base sketches.
3. Describe and apply the EXTRUDE command to extrude Base sketches to create the 3D Base model.
Dimensional Constraints
Unlike geometrical constraints, that are used to apply geometrical relationships between the objects in the sketch, dimensional constraints control and report the size of the geometry. Dimensional constraints are sometimes called parametric dimensions. To fully constrain a 2D sketch, driving dimensions must be applied. A driving dimension is a parametric dimension controlling the size of the object. Inventor will automatically change the overall model to conform to the driving dimensions maintaining the existing geometrical constraints that were assigned in the sketch. Objects of the sketch that are not dimensioned will change to adapt when a driving dimension is applied or an existing driving dimension is changed.
Add only the number of driving dimensions that are required to ensure that the model maintains the desired size and shape. Inventor will issue a warning when a dimension is added that over-constrains the sketch. Only driven dimensions will be allowed to be added to a fully constrained sketch.
A driven dimension is a non-parametric dimension that does not constrain the object. It only displays the current value of the geometry that it is applied to. Driven dimensions are automatically enclosed in parentheses to distinguish them from driving dimensions. You can add as many driven dimensions to the sketch as you wish.
Base Model
After the Base sketch is complete and is fully constrained, it is ready to be extruded or revolved to create the base model. The Base model is the solid model created from the base sketch by extruding or revolving it. In this module, only extruding the Base sketch to create the Base model is taught. The simplest definition of an extrusion is it adds depth to the Base sketch to create the Base model. See Figure 5-1.
Inventor Command: EXTRUDE
The EXTRUDE command is used to extrude a 2D sketch to create or edit a 3D solid model.
Shortcut: E
Dimensioning Sketches
There are many different types of dimensions available to the operator to dimension sketches. The different dimensioning types will be taught throughout the Inventor book. In this module, inserting object linear dimensions is taught.
Linear Dimensions
A linear dimension is a dimension measuring the delta X or the delta Y distance between the two XY locations or endpoints of a line. See Figure 5-2. Linear dimensions are always either horizontal (delta X) or vertical (delta Y). A linear dimension cannot be used to dimension the true length of an inclined line. It will only dimension the true length of a line if the line is horizontal or vertical. If both endpoints of a line lie on the same axis, it can only be dimensioned in one delta direction. Since all lines that were drawn to this point in the book were either horizontal or vertical, linear dimensions will be used for all of the dimensions inserted in this module.
Object Linear Dimensions
To insert an object linear dimension, enter the GENERAL DIMENSION command and move the cursor onto the line to be dimensioned. When the two headed arrow icon appears, click the left mouse button to select the line as shown in Figure 5-3. After selecting the line, move the cursor in the direction to select the location of the dimension. Click the mouse at the desired location of the dimension.
Inventor Command: GENERAL DIMENSION
The GENERAL DIMENSION command is used to create driving or driven dimensions on a sketch.
Shortcut: D
WORK ALONG: Dimensioning and Extruding the Base Sketch
Step 1
Using the OPEN command, open the part file: Inventor Workalong 04-1 that you completed in Module 4.
Step 2
Change to Sketch mode by editing Sketch1 in the Browser bar. Press F6 to change the view to the Home view. (Figure Step 2)
Step 3
Enter the LOOK AT command and when prompted, select one of the lines on the sketch as shown in the figure. (Figure Step 3A and 3B)
Step 4
Enter the GENERAL DIMENSION command by pressing D on the keyboard. Move the cursor onto the left vertical line. When the Two Headed Arrow icon appears, select the line by clicking the left mouse button. (Figure Step 4)
Step 5
Move the cursor to the left and drag the dimension. Inventor will measure the delta Y length of the line, since it is a vertical line, and display its actual length. In this case, it is 6.0 inches long. Since that is the desired length, accept it by clicking the green Check icon. (Figure Step 5)
Step 6
Continue to add linear dimensions to fully constrain your sketch. If the length of the lines are correct, accept the dimension. If they are incorrect, change the dimension in the edit box to the actual dimension of the line and then accept it by clicking the green Check icon. (Figure Step 6A, 6B, 6C, and 6D)
Step 7
When complete, there should be six driving dimensions. (Figure Step 7)
Step 8
Add one more dimension as shown in the figure. Note that Inventor will issue a warning that the dimension over-constrains the sketch. Click the Accept button to add it as a driven dimension. (Figure Step 8A and 8B)
Step 9
Without entering a command, move the cursor onto the 2.000 dimension as shown in the figure. When the Move icon displays, click and hold the mouse button down and drag the dimension to the new location shown in the figure. (Figure Step 9A and 9B)
USER TIP: Instead of clicking the green Check icon to accept the displayed dimension in the Edit Dimension dialogue box it is faster to press the Enter key.
Step 10
The completed sketch should appear as shown in the figures. (Figure Step 10A, 10B, and 10C)
Step 11
Press F6 to change to the Home view. (Figure Step 11)
Step 12
Click the LOOK AT command and change the view to the top or XY plane.
Step 13
Press F8 to display the geometrical constraint icons. You figure should appears similar as shown in the figure. (Figure Step 13)
Step 14
Enter the EXTRUDE command. The Extrude dialogue box will display. The model being drawn is 5 inches high as shown in the figure. Set the Output box to Solid, the Extents to Distance of 5 and the Extrude Direction to positive Z as shown in the figures. (Figure Step 14A and 14B)
Step 15
The completed solid model should now appear as shown in the figure. (Figure Step 15)
Step 16
Find the Appearance pull-down menu and select the arrow to pull down the Color list. Ensure that the library: Inventor Material Library is enabled at the bottom of the list. (Figure Step 16A and 16B)
Step 17
In the Appearance pull-down menu, select the color: Aluminum Polished as shown in the figure. (Figure Step 17)
Step 18
The completed part or model should appear as shown in the figure. (Figure Step 18)
Step 19
Save and close the part file.
MUST KNOW: A driving dimension is a parametric dimension controlling the size of the object. Inventor will automatically change the overall sketch to conform to the driving dimensions maintaining the existing geometrical constraints that were used in the design.
A driving dimension is shown below. A driven dimension is a non-parametric dimension that does not constrain the object. It is inserted for reference only and is always displayed enclosed in brackets as shown below.
USER TIP: When you open the Extrude dialogue box for the first time, the Marking menu will display on top of the extruded model. You will not be using that menu in the Inventor book.
USER TIP: Click the bottom right arrow and enable Pin Mini-Toolbar Position and Auto Fade.
Drag the Marking menu to bottom right corner of the Graphic window. It will remain there for the duration while you working on the Inventor book. After you complete the book, you can use change the settings to use the menu any way the works for you.
MUST KNOW: Knowing When the Sketch is Fully Constrained It is very important to know when a sketch is fully constrained. A fully constrained sketch is complete and is ready to be extruded or revolved to create or edit the solid model. When the colour scheme is set to High Contrast, the background is black and the lines that are constrained will display purple. The lines that are not yet constrained will display blue. When the sketch is fully constrained, all of the lines in the sketch will display purple. Inventor also reports the current constraint status on the Status bar. See the figures below.
A special Pinned icon will display in Browser bar on sketches that are fully constrained as shown to the figures.
Key Principles
Key Principles in Module 5
1. Unlike geometrical constraints, that are used to apply geometrical relationships of the objects in a 2D sketch, dimensional constraints control and report the size of the geometry.
2. To fully constrain a 2D sketch, driving dimensions must be applied. A driving dimension is a parametric dimension controlling the size of the object. Inventor will automatically change the overall object to conform to the driving dimensions maintaining the existing geometrical constraints that were assigned in the sketch.
3. A driven dimension is a non-parametric dimension that does not constrain the sketch.
4. It is very important to know when the sketch is fully When it is fully constrained, the sketch is complete and it is ready to be extruded or revolved to create the Base model. When the background colour scheme is set to High Contrast the constrained lines will display purple and lines that are not yet constrained will display blue. When the sketch is fully constrained, all of the lines in the sketch will display purple.
5. After the Base sketch is complete and is fully constrained, it is ready to be extruded to create the Base model. The Base model is the solid model created from the Base sketch.
Lab Exercise 5-1
Time allowed: 40 minutes.
Part Name Project Units Template Color Material
Inventor Lab 04-1 Inventor Course Inches English-Modules Part (in).ipt Zinc Chromate 2 N/A
Step 1
Open the file: Inventor Lab 04-1.ipt that you saved in Lab Exercise 4-1 in Module 4.
Step 2
Using the SAVEAS command, save the file with the name: Inventor Lab 05-1.ipt.
Step 3
Insert the necessary driving dimensions to fully constrain the sketch. Add at least one driven dimension. (Figure Step 3A, 3B, and 3C)
Step 4
Extrude the sketch to create the Base model and apply the colour shown above. (Figure Step 4)
Lab Exercise 5-2
Time allowed: 40 minutes.
Part Name Project Units Template Color Material
Inventor Lab 04-2 Inventor Course Inches N/A Chrome – Polished Blue N/A
Step 1
Open the file: Inventor Lab 04-2.ipt that you saved in Lab Exercise 4-2 in Module 4.
Step 2
Using the SAVEAS command, save the file with the name: Inventor Lab 05-2.ipt.
Step 3
Insert the necessary driving dimensions to fully constrain the sketch and add at least two driven dimensions. (Figure Step 3A, 3B, and 3C)
Step 4
Extrude the sketch to create the Base model and apply the colour shown above. (Figure Step 4) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.05%3A_Module_5_Extruding__Part_1.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a one hour time limit, complete a written exam and a lab exercise.
The Inventor book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are Completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after you have completed this module.
Multiple Choice Questions
Select the BEST answer.
1. What keyboard key is used to end the current command?
1. CTRL
2. TAB
3. ESC
4. SHIFT
5. ENTER
2. An Inventor _______________is designed to logically organize, store and manage the valid links to the files that are created for each undertaking.
1. 3D Model
2. Project
3. Design
4. 2D Sketch
5. Menu
3. What command is used to zoom the model or the 2D sketch to display the complete model or sketch in the graphic window?
1. ZOOM
2. PAN
3. ISOMETRIC
4. ZOOM ALL
5. LOOK AT
4. What are all files created in Inventor called?
1. Designs
2. Drawings
3. Files
4. 3D Models
5. 2D Sketches
5. What command is used to change the viewing position of the model or sketch to a known home view or isometric view?
1. ZOOM
2. PAN
3. HOME VIEW
4. ZOOM ALL
5. LOOK AT
6. What is the name of the Inventor file that must be used by the operator when creating any new file?
1. Design file
2. Drawing file
3. Model file
4. Template file
5. Sketch file
7. What term describes the process of applying geometrical relationships of objects to one another in a 2D sketch?
1. Object snapping
2. Dimensional constraints
3. Parametric solid modeling
4. Driven dimensions
5. Geometrical constraints
8. What file extension is assigned to a part file?
1. .IPT
2. .IJP
3. .IAM
4. .IDW
5. .IPN
9. When drawing a base sketch that must be extruded to create the solid model there is a list of rules that should be used. Which one of the following rules is false?
1. Select the view with the most complex contour shape.
2. Draw the lines using dimensions close to finished dimensions.
3. The objects in the sketch must meet at their endpoints and cannot overlap.
4. The objects in the sketch must have geometrical constraints applied to control the shape.
5. The objects in the sketch cannot be a closed polygon.
10. What term describes the process of controlling and reporting the size of the geometry in a 2D sketch?
1. Object snapping
2. Dimensional constraints
3. Parametric solid modeling
4. Driven dimensions
5. Geometrical constraints
Lab Exercise 6-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 06-1 Inventor Course Inches English-Modules Part (in).ipt Aluminum – Flat N/A
Step 1
Start a new part file with the template: English- Modules Part(in).ipt, and save the file with the name: Inventor Lab 06-1, as shown above.
Step 2
Project the Center Point onto the Base sketch.
Step 3
Draw the Base sketch for the object shown in the figure and apply all of the necessary geometrical constraints to maintain the shape of the sketch. Note the location of X0Y0Z0. (Figures Step 3A and 3B)
Step 4
Insert the necessary driving dimensions to fully constrain the sketch. Add at least 1 driven dimension.
Step 5
Ensure that the sketch is fully constrained and all lines display purple. (Figure Step 5)
Step 6
Extrude the sketch to complete the Base model and apply the color: Aluminum – Flat (Figure Step 6) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/01%3A_Part_1/1.06%3A_Module_6_Competency_Test_No._1_Open_Book.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how to construct a solid model using multiple sketches, linear dimensions, plus joining and cutting extrusions.
2. Describe and apply the 2DSKETCH command to create 2D sketches on a solid model. Extrude the sketches to either join them to or cut them from the solid model.
Point to Point Linear Dimensions
A point to point linear dimension is a dimension measuring the delta X or the delta Y distance between two points of an existing object or objects. The points, which are normally the endpoints of a line, could also be centre points of circles or arcs as you will see in future modules. If the points both lie on the same X or Y axis, the dimension can only inserted in one direction. If the points do not lie on the same axis, you have the choice of inserting either the delta X or the delta Y dimension. See Figure 7-1. The three steps used to insert a point to point linear dimension are shown below.
Inventor Command: 2D SKETCH
The 2D SKETCH command is used to create a 2D sketch on a sketching plane or onto an existing 3D solid model.
Shortcut: S
WORK ALONG: Constructing a Solid Model Using Multiple Sketches
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Enter the NEW command to start a new part file using the template: Metric-Modules Part (mm).ipt.
Step 3
Save the file with the name: Inventor Workalong 07-1. (Figure Step 3A and 3B)
Step 4
Edit Sketch 1 and enter the PROJECT GEOMETRY command and project the Center Point onto the sketching plane. Press Esc to exit the command. (Figure Step 4)
Step 5
Draw the Top view of the model starting at X0Y0Z0. This is the Base sketch. (Figure Step 5)
Step 6
Add 4 driving dimensions to fully constrain the sketch. Add 2 driven dimensions.
Step 7
Press F8 to display the constraints. (Figure Step 7)
Step 8
The sketch should now be fully constrained and all the lines display purple on a black background. (Figure Step 8)
Step 9
Press F6 to change the view to the Home view. Click the FINISH SKETCH command to return to Model mode. (Figure Step 9)
Step 10
Enter E to execute the EXTRUDE command and extrude the model 100 mm in the positive Z direction. (Figure Step 10)
Step 11
The solid model should appear as shown in the figure. (Figure Step 11)
Step 12
Click the 2D SKETCH icon and when prompted, select the right side plane as shown in the figure. Exit the command and the grid will display on the plane in Sketch mode. Press F6 to change to the Home view. (Figure Step 12A, 12B, and 12C)
Step 13
Enter L for the LINE command and start the first endpoint of the line by snapping onto the plane edge line. (Figure Step 13)
Step 14
Draw three lines, applying perpendicular geometrical constraints and snapping back onto the edge. Guess at the length of the lines making them approximately the correct length. (Figure Step 14)
Step 15
Press F8 to display the constraint icons. (Figure Step 15)
Step 16
Enter D for the GENERAL DIMENSION command. Move the cursor to bottom corner of the model. When a small point highlights, click the mouse. (Figure Step 16)
Step 17
For the second point of the dimension, click the end of the line as shown in the figure. Locate and set the dimension to 25. (Figure Step 17A and 17B)
Step 18
Add two additional dimensions to fully constrain it. (Figure Step 18A, 18B, and 18C)
Step 19
Enter E for the EXTRUDE command. (Figure Step 19)
Step 20
Set the Extents to To, the type to Cut and select the back face to locate where to extrude to. (Figure Step 20)
Step 21
Your model should appear as shown in the figure. (Figure Step 21)
Step 22
Click the 2D Sketch icon and select the top plane to start a new sketch. Orbit the model to match the figure. (Figure Step 22)
Step 23
On the sketch, draw a line across the corner. Make sure that you snap both ends of the line to the edges. Guess at the distance from the corner. (Figure Step 23)
Step 24
Draw a line on the opposite side and dimension both lines using four point to point dimensions. (Figure Step 24)
Step 25
Your sketch should be fully constrained as shown in the figure. (Figure Step 25)
Step 26
Press F8 to display the constraint icons. (Figure Step 26)
Step 27
Extrude the sketch using the To Next extents. Select the two profiles to extrude and ensure that you enable the Cut icon. (Figure Step 27)
USER TIP: Drawing lines on the plane of a 3D model works a little different then drawing lines on a 2D sketch before the model is extruded. In most cases, Inventor will only allow you to draw one line segment at time when you are drawing a line on the 3D model. Watch the prompts in the Status bar and you will know when you have to reenter the start point again or you can draw the next segment continuous.
Step 28
Change to the Home view by pressing F6. Change the colour of the completed model to color: Light Steel Blue. (Figure Step 28)
Step 29
Expand the Browser bar. You can see that the model hierarchy shows the three sketches and an extrusion of each one. (Figure Step 29)
Step 30
Save and close the file.
Key Principles
Key Principles in Module 7
1. A point to point linear dimension is a dimension measuring the delta X or the delta Y distance between two points of an existing object or objects.
2. The 2D SKETCH command is used to create a 2D sketch on a sketching plane or onto an existing 3D solid model.Lab Exercise 7.1
Lab Exercise 7-1
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab 07-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Steel N/A
Step 1
Project the Center Point onto the sketching plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3)
Lab Exercise 7-2
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab 07-2 Inventor Course Millimeters Metric-Modules Part (mm).ipt Chrome – Polished N/A
Step 1
Project the Center Point onto the base sketching plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A, 2B, and 2C)
Step 3
Apply the colour shown above. (Figure Step 3)
Step 4
Save the file with the name: Inventor Lab 07-2 as shown above. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/02%3A_Part_2/2.01%3A_Module_7_Extruding__Part_2.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe multiview drawings, the glass box principle, the three standard views, object lines, and hidden lines.
2. From a 3D pictorial of an object, draw a multiview drawing using the three standard views.
NOTE: If you understand multiview drawings, object lines, hidden lines, and you can draw the three standard views of an object, skip this module.
Multiview Drawing
The drafting and design world uses a system of representing a three- dimensional object by drawing two-dimensional views. It is called a multiview drawing. To explain this system of drawing, the object shown in Figure 8-1 will be used in this module. To draw a two-dimensional view of one side of the object, place a imaginary plane parallel to the side and project the view of the object perpendicular onto the plane. This is called orthographic projection. Imagine the plane to a sheet of glass. See Figure 8-2.
The Glass Box Principle
To carry this principal further, place a plane on each side of the object for a total of six planes or sheets of glass to form a glass box. This is called the Glass Box Principle, see Figure 8-3. Picture unfolding the glass box onto a flat two-dimensional plane as shown in Figure 8-4. All six views are now visible at the same time.
The Three Standard Views
In almost all objects, three views are adequate to describe it. In fact, there are many objects that only need two views and some that only need one view to describe it. The six views are Top, Front, Right Side, Left Side, Rear, and Bottom. The three standard views are the Top, Front, and Right Side. They must be drawn in the positions shown in Figure 8-5 and they must be aligned.
Picking the Standard Three Views
The three standard views are always selected as shown in Figure 8-6.
Drawing the Views
Usually it is best to draw the view with the most irregular shape first and then project lines to the other two views. For the object in Figure 8-7, the front view should be drawn first and then the top and right side views are projected. Notice how the views have to align. Figure 8-7 shows two different methods of projecting lines from the top view to the right side view or vise versa. The distance between the views is not important.
Drafting Lesson Object and Hidden Lines
Lines and features that can be seen in the views are drawn with continuous or solid lines. They are called object lines. Even though they are called object lines, they can be circular in shape. To completely describe an object in a multiview drawing, the drafter must also show all lines or features that are hidden in that view. They are called hidden lines and their linetype is dashed. Study the multiview drawing below and take note how the holes going through the object are shown with hidden lines. See Figures 8-8 and 8-9.
Key Principles
Key Principles in Module 8
1. The drafting and design world uses a system of representing a three-dimensional object by drawing two-dimensional This is called a multiview drawing.
2. The three standard views of a multiview drawing are the Top, Front, and Right Side.
3. When drawing a multiview drawing, the three standard views of an object must be drawn in the correct position and must be aligned. The distance between the views is not important.
Lab Exercise 8-1
Time allowed: 15 minutes.
Step 1
Sketch the Top, Front and Right Side views of the Object 8-1.
Step 2
Use one grid on the model equal to one grid on the drawing. See the example.
Step 3
When complete, check your answers at the end of this chapter.
Lab Exercise 8-2
Time allowed: 60 minutes.
Step 1
Sketch the Top, Front, and Right Side views of each model.
Step 2
Use one grid on the model equal to one grid on the drawing.
Step 3
Check your answers at the end of this chapter. Do not look at the answers until you have completed your sketch. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/02%3A_Part_2/2.02%3A_Module_8_Multiview_Drawings.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Using multiview drawings, visualize and sketch isometric drawings of 3D models on isometric grid paper.
Visualizing 3D Models
In the first six modules, all of the wireframe models that you constructed were referenced to a given 3D view of the model. Since most technical drawings used in the drafting and design world are 2D multiview drawings, 3D models must be able to be drawn using a multiview drawing as a reference to find the model’s shape and dimensions. To construct a 3D model, you must be able to mentally visualize the 3D model using a multiview drawing as a reference.
.A good way for you to learn to visualize a 3D model from a 2D multiview drawing is to first draw the model as an isometric drawing. By doing this, it is easier to form a mental image from the multiview drawing. After practicing this for while, you will be able to visualize and construct 3D models without drawing the isometric first.
An isometric drawing is a 2-dimensional drawing that has the XYZ axis drawn at 120 degrees apart as shown in Figure 9-1. In this module, drawing the isometric on an isometric grid will be taught. An isometric grid has the grid lines drawn at 120 degrees as shown in Figure 7-2. Figure 9-3 shows a rectangular box drawn on the isometric grid.
WORK ALONG: Sketching an Isometric Drawing of a 3D Model – Part 1
This workalong demonstrates how the multiview drawing of the 3D model, shown in Figure 9-4, is drawn as an isometric drawing.
Step 1
Using a pencil and eraser, complete this workalong to create the isometric sketch of the 3D model. (Figure Step 1)
Step 2
Sketch the rectangular box using the length, width, and height of the overall size of the 3D model. The overall size of the 3D model is 6 grids long, 5 grids wide and 5 grids high. (Figure Step 2)
Step 3
Cut the shape away, one view at a time. Draw the Front view first. (Figure Step 3A and 3B)
Step 4
In the Right Side view, remove the top left side of the object to match the multiview’s right side view. (Figure Step 4)
Step 5
In the Top view, remove the bottom right corner to complete the isometric drawing. (Figure Step 5A and 5B)
WORK ALONG: Sketching an Isometric Drawing of a 3D Model – Part 2
This workalong demonstrates how the multiview drawing of the 3D model, shown in Figure 9-5, is drawn as an isometric drawing.
Step 1
Using a pencil and eraser, complete this workalong to create the isometric sketch of the 3D model. (Figure Step 1)
Step 2
The figures show the necessary steps. Try to complete the isometric without looking at the figure. (Figure Step 2A, 2B, 2C, and 2D)
Key Principles
Key Principles in Module 9
1. 1 An isometric drawing is a 2-dimensional drawing that has the XYZ axis drawn 120 degrees apart.
2. To sketch an isometric circle, first consider which one of the three isometric planes it is located on.
Lab Exercise 9-1
Time allowed: 90 minutes.
Step 1
Using the 4 multiview drawings shown below, using pencil and eraser and the graph paper you printed, sketch the isometric drawing of each 3D model.
Step 2
Using what was just taught, draw isometric drawings of the four objects: Object 9-1 to Object 9-4. For the answers, see the end of this chapter. Try to visualize the 3D model by looking at the multiview drawing and then draw the isometric. Do not look at the answers until you have done your best to complete the isometric drawing of each object. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/02%3A_Part_2/2.03%3A_Module_9_Visualizing_3D_Models.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe the three predefined 2D sketching planes and the view of the model that they are on.
2. Construct solid models by drawing the Base sketch on either the Front or Right Side instead of the default Top view.
3. Describe a consumed and an unconsumed sketch.
2D Sketching Planes
Up to this point in the book, the Base sketch has been drawn on the XY plane. The XY plane is the Top view of the model and the default plane as configured in the templates that are being used to complete the workalongs and lab exercises in the Inventor book. The models that have been constructed up to this point in the modules were all designed so that the Base sketch was drawn on the XY plane or the Top view. In this module, learning how to construct solid models by drawing the Base sketch on either the front or right side planes will be taught.
Inventor has p three predefined planes that can be used to draw the Base sketch. They are the XY, XZ, and YZ planes. The XY plane is the Top view, the XZ plane is the Front view and the YZ is the Right Side view of the model.
Keep in mind the rule that was taught in Module 4. ‘ It is best to draw the Base sketch on the plane that has the most complex contour. Contours with arcs and curves should be avoided ‘.
The Three Predefined Planes
To help visualize the three predefined planes used in Inventor, the 3D model shown in Figure 10-1 is used in this module. The glass box principle that was taught in Module 8 is used to help you visualize Inventor’s three predefined planes. See Figure 10-2.
Consumed and Unconsumed Sketches
A consumed sketch is a 2D sketch that has been extruded or revolved to create a 3D solid model. An unconsumed sketch is a 2D sketch that is blank or one that has not been extruded or revolved.
The Browser bar will display which sketches have been consumed and which ones are unconsumed. See Figure 10-3. Sketch1 is unconsumed while Sketch2, Sketch3, and Sketch4 have been extruded and are consumed.
USER TIP: A 2D sketch can be drawn in the orthographic view or in the 3D Home view. In fact, any 3D orbited view can be used. When drawing in a 3D view, it is always best to draw in the Home view since this helps you maintain a good mental picture of the model.
MUST KNOW: Inventor has three predefined planes that can be used to draw the Base sketch on. They are the XY, XZ and YZ planes. The XY plane is the Top view, the XZ plane is the Front view and the YZ is the Right Side view of the Base model.
WORK ALONG: Working with 2D Sketching Planes
Step 1
Start a new part file using the template: English-Modules Part (in).ipt.
Step 2
In Sketch mode, press F6 to change to the Home view. The Graphic window and the Browser bar will appear as shown in the figure. (Figure Step 2)
Step 3
In the Browser bar, expand the folder: Origin as shown in the figure. Place the cursor on the XY Plane. Note the orientation of the plane on the sketch. (Figure Step 3)
Step 4
Place the cursor on the XZ Plane in the Browser bar. Note the orientation of the plane on the sketch. The XZ Plane is the Front view. (Figure Step 4)
Step 5
Place the cursor on the YZ Plane in the Browser bar. Note the orientation of the plane on the sketch. This is the Right Side view. (Figure Step 5)
Step 6
Place the cursor anywhere in the Graphic window and right click the mouse. In the Right-click menu, click Finish 2D Sketch.
Step 7
Save the part file with the name: Inventor Workalong 10-1. In Model mode, expand the folder: Origin in the Browser bar and right-click the XZ plane. In the Right-click menu, click New Sketch as shown in figure. (Figure Step 7)
Step 8
The Graphic window will change to Sketch mode. Change to the Home view. Note that in the Browser bar a new sketch will appear and named Sketch2. (Figure Step 8)
Step 9
Project the Center Point onto the sketch plane. Draw the Base sketch for the model applying all of the necessary geometrical constraints to maintain the shape of the sketch. Note the location of X0Y0Z0. Insert the necessary driving dimensions to fully constrain the sketch. (Figure Step 9)
Step 10
Press PAGE UP key to execute the LOOK UP/VIEW FACE command. Select one of the lines to change the sketch to the 2D view of the the XZ plane. Press F8 to display the geometrical constraint icons. They should appear similar to the figure. (Figure Step 10)
Step 11
Right-click anywhere in the Graphic window. In the Right-click menu, click Finish 2D Sketch to return to Model mode. (Figure Step 11)
Step 12
Save the part with the name: Inventor Workalong 10-1. Extrude the sketch to create the solid model as shown in figure. (Figure Step 12)
Step 13
Using the 2D SKETCH command, or even better the shortcut S, start a new sketch and select the right side as the plane to draw it on. (Figure Step 13)
Step 14
The grid will display on the right side. It will be Sketch3 in the Browser bar. (Figure Step 14)
Step 15
Draw three lines for the slot. Apply all of the necessary geometrical and dimensional constraints to fully constrain the sketch. (Figure Step 15)
Step 16
Press F8 to enable the display of the constraint icons. They should be similar to the figure. (Figure Step 16)
Step 17
Press F9 to disable the display of the constraint icons. Extrude the sketch using the To next. (Figure Step 17)
Step 18
Start a new sketch on the top plane as shown in the figure. (Figure Step 18)
Step 19
Draw the 2D sketch on the new sketching plane and insert the necessary dimensions to fully constrain it. (Figure Step 19)
Step 20
Extrude the top sketch to complete the solid model. (Figure Step 20)
Step 21
Change the view to the Home view and apply the color: Chrome – Polished Black. Orbit the model to check the bottom. (Figure Step 21)
Step 22
Save and close the file.
Key Principles
Key Principles in Module 10
1. Inventor has three predefined planes that can be used to draw the Base sketch on. They are the XY, XZ and YZ planes. The XY plane is the Top view, the XZ plane is the Front view, and the YZ is the Right Side view of the Base model.
2. A consumed sketch is a 2D sketch that has been extruded or revolved. An unconsumed sketch is a 2D sketch that is blank or one that has not been extruded or revolved.
Lab Exercise 10-1
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 10-1 Inventor Course Inches English-Modules Part (in).ipt Titanium – Polished N/A
Step 1
Project the Center Point onto the base sketching plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour as shown above. (Figure Step 3)
Lab Exercise 10-2
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 10-2 Inventor Course Millimeters Metric-Modules Part (mm).ipt Zinc Chromate 2 N/A
Step 1
Project the Center Point onto the base sketching plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3)
2.05: Module 11 Competency Test No. 2 Open Book
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a one hour time limit, complete a written exam and the lab exercise.
If you are Completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after you have completed this module.
Multiple Choice Questions
Select the BEST answer.
1. What view of the model is the XZ plane in Inventor?
1. Left Side
2. Right Side
3. Top
4. Bottom
5. Front
2. Which one of Inventor’s menus shows if a sketch is consumed or unconsumed?
1. Status bar
2. Standard menu
3. Browser bar
4. Panel bar
5. 2D Sketch panel
3. What command is used to draw a 2D Sketch on the existing solid model?
1. NEW
2. LOOK AT
3. 2D SKETCH
4. EXTRUDE
5. LINE
4. Which plane is the default plane used in the templates supplied with the Inventor book?
1. ZY
2. XZ
3. XY
4. YX
5. YZ
5. Which of the following best describes a consumed 2D sketch?
1. It is blank.
2. It has been extruded or revolved to create a 3D feature.
3. It has been deleted.
4. It cannot be edited.
5. It has been dimensioned.
6. In Figure 11-1, what is the purpose of the middle icon in the EXTRUDE dialogue box?
1. Cut
2. Subtract
3. Add
4. Join
5. Intersect
7. What kind of dimension does a linear dimension insert?
1. Line
2. Object
3. Horizontal only
4. Vertical only
5. Delta X or Delta Y
8. What view of the model is the XY plane in Inventor?
1. Left Side
2. Right Side
3. Top
4. Bottom
5. Front
9. On the colour scheme High Contrast, what colour will the sketch appear when it is fully constrained?
1. Black
2. White
3. Purple
4. Blue
5. Green
10. What view of the model is the YZ plane in Inventor?
1. Rotated
2. Right Side
3. Top
4. Bottom
5. Front
Lab Exercise 11-1 Part B
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 11-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Orange N/A
Step 1
Project the Center Point onto the Base sketch.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. Ensure that all lines on all sketches display purple on a black background. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3A, 3B, and 3C) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/02%3A_Part_2/2.04%3A_Module_10_2D_Sketching_Planes.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe construction objects and their use in a 2D sketch.
2. Describe drawing circles and offsets in a 2D sketch.
3. Apply the CENTER POINT CIRCLE and OFFSET commands to complete 2D sketches.
Geometry Lesson: Circles
A circle is defined as a closed curve in which all points are the same distance from its centre point. The centre point is a single XY coordinate. A circle is 360 degrees and can be divided into four quadrants. All points on a circle are at a given distance from is centre point. The distance between any of the points and the centre is called the radius.
Study the drawings in Figure 12-1, 12-2, 12-3, and 12-4 for a description of the geometry of a circle.
Drafting Lesson: Reading Dimensions for Circles and Arcs
When reading the dimensions for circles and arcs, consider the following: Circles are dimensioned as diameters. For example: 2.0 DIA.
Arcs are dimensioned as radii. For example: 1.5 R
When there is more than one circle of the same diameter, they are only dimensioned once. For example: 0.5 DIA., 4 PLACES
Sometimes multiple arcs are dimensioned as typical (TYP.). For example: 2.0 R TYP. This simply means that there is at least one additional arc of the same size, See Figure 12-5.
Inventor Command: CENTER POINT CIRCLE
The CENTER POINT CIRCLE command is used to draw a circle by entering the location of its centre point and its radius.
Shortcut: C
Inventor Command: OFFSET
The OFFSET command is used to draw an object parallel to an existing object.
Shortcut: O
Construction objects are objects that are drawn in the sketch to assist you to complete the sketch but will be ignored by Inventor when the sketch is extruded or revolved to create the Base model. Geometrical and dimensional constraints can be applied to construction objects the same as they are to drawing objects. Construction objects and drawing objects only differ in the properties of the objects. They are both drawn and manipulated the same way in a 2D sketch.
There are two methods of creating construction objects as follows:
Method 1
Enable the Construction icon, see Figure 12-6, and then draw the objects. All objects drawn while the Construction icon is enabled, will be created as construction objects.
Method 2
Draw the object with the Construction icon disabled. After the drawing object(s) is created, select it. While it is selected, click the Construction icon. Construction objects will appear as a dashed lines as shown in Figure 12-7.
USER TIP: Some commands require you to select one or more drawing objects when there is no command active. For example, the DELETE command. The Status bar will display Ready when there is no command active. To select one object at a time, select the object by clicking it with the left mouse button. The selected object will highlight and change colour. To select more then one object at time, hold down either the CTRL or SHIFT key while selecting the objects. When all objects have been selected, click the command icon or enter the command on the command line.
WORK ALONG: Drawing Circles and Cylindrical Models
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Enter the NEW command to start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 12-1. (Figure Step 3A and 3B)
Step 4
Draw the Base sketch on the Top view. Since this is the XY plane (the default plane), use Sketch1.
Step 5
Project the Center Point onto the sketching plane.
Step 6
Enter the CENTER POINT CIRCLE command and draw a 4.0 inch diameter circle. Watch the Status bar. The first prompt will be to select the centre point for the circle. For the centre point location, snap to the Center Point that was projected onto the sketching plane. Select the radius by guessing 2 inches from the centre. (Figure Step 6)
Step 7
Click the OFFSET command and when prompted, select the circle. Right-click the mouse. In the Right-click menu, ensure that Loop Select is enabled. Move the mouse towards the centre, guess at the diameter size of the 1.0 inch. (Figure Step 7A, 7B, and 7C)
Step 8
Click the Construction icon to enable it. (Figure Step 8)
Step 9
Using what you just learned, enter the OFFSET command and offset the large circle to draw the 3 inch diameter construction circle. (Figure Step 9)
Step 10
Click the Tools menu. Click the Applications Options icon to open the Applications Options dialogue box. Enable the Sketch tab. In the Display area, disable Axes. Click OK to close the dialogue box. (Figure Step 10A and 10B)
Step 11
Dimension the three circles. Press F8 to display the geometrical constraint icons. (Figure Step 11)
Step 12
Using the LINE command, draw a line by first snapping to the Center Point and ending it by snapping onto the circle. Make sure that the Horizontal constraint icon displays when you are drawing the line. The constraint icons should appear similar to the figure. (Figure Step 12)
Step 13
Using the LINE command, draw three additional construction lines by first snapping to the Center Point and ending them by snapping onto the circle. The constraint icons should appear similar to the figure. (Figure Step 13)
Step 14
Press F8 to display the constraint icons. (Figure Step 14)
Step 15
Click the Construction icon to disable it.
Step 16
Enter the CENTER POINT CIRCLE command. With the cursor in the sketching window, right-click the mouse. In the Right-click menu, select Intersection. Select the construction circle and then the construction line. Notice how the cursor will display a plus sign beside it. When you select the line, the green snap indicator will display. Select a location for the radius of the circle by guessing at its size. (Figure Step 16A, 16B, 16C, and 16D)
Step 17
Using what you just learned in Step 14, insert the 3 additional circles. For now, the diameter of the circles is not important. (Figure Step 17)
Step 18
Dimension one circle only. (Figure Step 18)
Step 19
Ensure that there is no active command and select the Equal constrain icon. (Figure Step 19)
Step 20
For the first circle, select the top (dimensioned circle) and for the second circle select one of the other circles. It will constrain the second circle as equal in size to the dimensioned circle. (Figure Step 20A and 20B)
Step 21
Using what you learned in Step 20, constrain the additional 2 circles with the Equal constraint to equal the dimensioned circle. The constraint icons should appear similar to the figure. (Figure Step 21)
Step 22
Change the view to the Home view. The sketch should be fully constrained and display purple. (Figure Step 22)
Step 23
Extrude the sketch as shown in the figure. (Figure Step 23A and 23B)
Step 24
Start a new sketch on the top plane of the model. Using the OFFSET command, offset the outside diameter of the object to insert a 1.5 inch circle. Add the diameter dimension as shown in figure. (Figure Step 24)
Step 25
Extrude the sketch as shown in figure. (Figure Step 25)
Step 26
Change the colour to: Chrome -Polished Black. (Figure Step 26)
Step 27
Save and close the file.
Key Principles
Key Principles in Module 12
1. Construction objects are objects that are drawn in the sketch to assist you in completing the sketch but will be ignored by Inventor when the sketch is extruded or revolved. Geometrical and dimensional constraints can be applied to construction objects the same as they are to drawing Construction objects and drawing objects only differ in the properties of the objects. They are both drawn and manipulated the same way in a 2D sketch.
2. To select more then one object at time, hold down either the CTRL or SHIFT key while selecting the objects.
Lab Exercise 12-1
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 12-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Aluminum – Flat N/A
Step 1
Project the Center Point onto the Base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3A and 3B)
Hint:
The small holes do NOT go all the way through the flange.
Lab Exercise 12-2
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 12-2 Inventor Course Inches English-Modules Part (in).ipt White N/A
Step 1
Project the Center Point onto the base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Hint
Draw the base sketch on the Front view or XZ plane.
Step 3
Apply the colour shown above. (Figure Step 3A and 3B) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/03%3A_Part_3/3.01%3A_Module_12_Circles.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe the geometry of an arc and how arcs are drawn in Inventor.
2. Describe how to snap to midpoints of lines.
3. Apply the CENTER POINT ARC command to draw arcs in 2D sketches.
Drawing Arcs
There are three commands available to draw arcs in Inventor. In this module, drawing arcs using the CENTER POINT ARC command will be taught. Similar to the CIRCLE command, the CENTER POINT ARC command also requires you to select the centre point and the radius. Drawing arcs additionally require you to locate the start point and end point or the arc. Arcs can be constructed clockwise or counterclockwise.
Geometry Lesson: Arcs
An ARC is defined as an open curve in which all points are the same distance from its centre point. Study the drawings in Figure 13-1 and 13-2.for a description of the geometry of an arc.
Inventor Command: CENTER POINT ARC
The CENTER POINT ARC command is used to draw an arc by entering the location of its centre point, radius, start point and end point.
Shortcut: A
WORK ALONG: Drawing Models with Arcs
Step1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Enter the NEW command to start a new part file using the template: Metric-Modules Part (mm).ipt.
Step 3
Save the file with the name: Inventor Workalong 13-1. (Figure Step 3A and 3B)
USER TIP: When drawing arcs, do your best to tie the centre point, the start point, and the end point to existing geometry. It will decrease the number of dimensions that are required to constrain the arc.
Step 4
Edit Sketch1. Project the Center Point onto the sketch.
Step 5
Draw a sketch of the Top view of the model. Apply all of the geometrical and dimensional constraints to fully constrain it. (Figure Step 5)
Step 6
Extrude the sketch in the positive Z direction. (Figure Step 6)
Step 7
Start a new sketch on the right side as shown in the figure. (Figure Step 7)
Step 8
Enter the CENTER POINT ARC command and when prompted for the centre point, right click the mouse. In the Right-click menu, select Midpoint. (Figure Step 8)
Step 9
Move the cursor onto the vertical edge. When the green snap icon appears, click the left mouse button. (Figure Step 9)
Step 10
Move the cursor approximately 10 mm along the edge and when the Snap onto icon displays, click the mouse. (Figure Step 10)
Step 11
Move the cursor to the other side of the centre and when the Snap onto icon displays, click the mouse. (Figure Step 11)
Step 12
Press F8 to display the constraint icons. (Figure Step 12)
Step 13
Move the cursor onto the Coincident icon and note the display of two coincident icons. (Figure Step 13)
Step 14
In the Graphic window, right click the mouse. In the Right-click menu, click Create Constraint and then Coincident. (Figure Step 14)
Step 15
Select the edge for the first point. (Figure Step 15)
Step 16
For the second point, move the cursor onto the endpoint of the arc. When a small red point will displays, click the mouse. (Figure Step 16)
Step 17
Press F8. Locate the cursor onto the Coincident icon and note the display of two coincident icons. (Figure Step 17)
Step 18
The arc should now display purple indicating it is fully constrained. (Figure Step 18)
Step 19
Finish the sketch and extrude the arc by using the Cut option. (Figure Step 19)
Step 20
Start a new sketch on the front side. (Figure Step 20)
Step 21
Draw a line perpendicular from the midpoint of the edge. (Figure Step 21)
Step 22
Change the line to a construction line by selecting the line and then click the Construction icon. (Figure Step 22A, 22B, and 22C)
Step 23
Offset the construction line on each side. (Figure Step 23)
Step 24
Insert two dimensions. (Figure Step 24)
Step 25
Draw an arc locating the centre at the end of the construction line. (Figure Step 25)
Step 26
Insert the required dimensions to constrain the sketch. (Figure Step 26)
Step 27
Enable the display of the constraint icons. (Figure Step 27)
Step 28
Use what you learned in Step 14 to 17, create the additional Coincident constraints to fully constrain the sketch. (Figure Step 28)
Step 29
Extrude the sketch to complete the model. (Figure Step 29)
Step 30
Change the colour to: Titanium – Polished. (Figure Step 30).
Step 31
Save and close the file.
Key Principles
Key Principles in Module 13
1. There are three commands available to draw arcs in Inventor. Similar to the CIRCLE command, the CENTER POINT ARC command also requires you to select the location of the centre point and the radius. Drawing arcs additionally requires you to locate the start point and end point or the arc. Arcs can be constructed clockwise or counterclockwise.
2. When drawing arcs, do your best to tie the centre point, the start point, and the end point to existing geometry. This will decrease the number of dimensions that are required to constrain the arc.
Lab Exercise 13-1
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 13-1 Inventor Course Inches English-Modules Part (in).ipt Chrome – Polished N/A
Step 1
Project the Center Point onto the Base sketch.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3)
Lab Exercise 13-2
Time allowed: 45 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 13-2 Inventor Course Millimeters Metric-Modules Part (mm).ipt Copper – Satin N/A
Step 1
Project the Center Point onto the Base sketch.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/03%3A_Part_3/3.02%3A_Module_13_Arcs.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe a centerline object and explain how it is inserted and used in a 2D Sketch.
2. Describe how a Base sketch is revolved with and without the use of a centerline to create a solid model.
3. Apply the REVOLVE command to create a solid model from a Base sketch.
Revolving
When drawing symmetrical objects it is much easier to create the model by revolving the Base sketch around an axis rather then extruding it. The axis, which can be one of the lines in the sketch or a centerline, must always be located in the centre of the symmetrical model. The sketch can be revolved any angle between 0 and 360 degrees.
In this module, the basic features of the REVOLVE command are taught. The Inventor Advanced book will cover the more advanced features.
The models in Figure 14-1 and 14-2 were created by revolving the same Base sketch around an axis. Take note how the two solid models that were created using the same sketch are quite different. In Figure 14-1, the line on left side of the sketch was used as the axis while in Figure 14-2, it was the centerline that was used as an axis or revolution.
Inventor Command: REVOLVE
The REVOLVE command is used to create a solid model by revolving the Base sketch around an axis.
Shortcut: R
Centerlines
A centerline is a line with its properties set to act as a centerline. In the REVOLVE command, a centerline is automatically recognized as the axis for the revolution. The two methods of drawing a centerline, which is similar to drawing construction a line, are as follows:
Method 1
Draw the line using the LINE command and then select it. While it is selected, click the Centerline icon.
Method 2
Enable the Centerline icon and then draw the line, using the LINE command. The Centerline icon is shown in Figure 14-3. A centerline will display as the centerline linetype.
WORK ALONG: Revolving a Sketch Without using a Centerline
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command, start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 14-1. (Figure Step 3A and 3B)
Step 4
Start a new sketch on the Front or XZ Plane. Project the Center Point onto the sketch.
Step 5
Draw and dimension one-half of the Front view as shown in the figure. Ensure that the sketch is fully constrained (Figure Step 5)
Step 6
In Model mode, enter the REVOLVE command. It will highlight the sketch automatically as the area to revolve. (Figure Step 6)
Step 7
In the Revolve dialogue box, set the Extents to Full and enable the Axis icon. Select the line on the right side of the sketch as the axis. The Full setting means that it will be revolved 360 degrees. (Figure Step 7)
Step 8
After you select the axis, the REVOLVE command will display the Base model as it is revolved. If this is the desired outcome, click OK. (Figure Step 8A and 8B)
Step 9
Start a new sketch on the top plane of the model. (Figure Step 9)
Step 10
Using what you learned in Module 12, draw a construction circle and four construction lines. Insert a dimension for the diameter of the circle. Ensure that the sketch is fully constrained. (Figure Step 10)
Step 11
Using the technique that you learned in Module 12, draw the 4 circles. Dimension one and constrain the additional 3 with an Equal constraint. (Figure Step 11A and 11B)
Step 12
Extrude the four circles to the To Next extents. (Figure Step 12)
Step 13
Start another sketch on the top plane and draw a circle by offsetting the outside diameter. Dimension the circle and extrude it to complete the model. (Figure Step 13)
Step 14
Change the colour to: Aluminum – Polished. (Figure Step 14)
Step 15
Save and close the file.
WORK ALONG: Revolving a Sketch using a Centerline
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Enter the NEW command to start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 14-2. (Figure Step 3)
Step 4
Start a new sketch on the Front or XZ Plane. Draw and dimension a line start it by snapping to the Center Point. Draw it 5 inches in the negative Y direction. This is the length of the model. This is centerline of the solid model. Change the line’s properties to a centerline. (Figure Step 4A and 4B)
Step 5
Draw and dimension one-half of the Front view as shown in the figure. (Figure Step 5A and 5B)
Step 6
Return to Model mode and enter the REVOLVE command. Since a centerline is part of the sketch, the REVOLVE command will automatically use it as the axis to revolve the sketch around. It will display the outcome of the revolution. (Figure Step 6)
Step 7
In a new sketch, add the four smaller circles and extrude them to complete the model.
Step 8
Change the colour to: Aluminum – Polished. (Figure Step 8)
Step 9
Save and close the file.
Drafting Lesson: Cross Sections
When a view of an object requires a clearer description of its interior or it is hard to dimension because of the hidden lines, a cross section view can be drawn in place of the normal multiview. See Figure 32-1
A cross section view, also called a section, is a view of the object as if it were cut along a cutting plane and the two pieces pulled apart exposing the inside of the object. See Figure 32-2 and 32-3.
A cutting plane line is the line along the object where the cut would have been made. See Figure 32-2. The arrows point in the direction that you are looking when drawing the section view. The surfaces of the object that are solid, when cut, are crosshatched.
Key Principles
Key Principles in Module 14
1. When drawing symmetrical objects, it is much easier to create the model by revolving the Base sketch around an axis rather then extruding it. The axis, which can be one of the lines in the sketch or a centerline, must always be located in the centre of the symmetrical MODEL.
2. A centerline is a line with its properties set to act as a centerline.
Lab Exercise 14-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 14-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Copper – Polished N/A
Step 1
Project the Center Point onto the Base plane.
Step 2
Note the location of X0Y0Z0. Draw the Base sketch and revolve it create the Base model of the object shown below. Revolve it by using a line in the sketch. Do not draw a centerline. (Figure Step 2A and 2B)
Step 3
Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches.
Step 4
Apply the colour shown above. (Figure Step 4A and 4B)
Step 5
Add the four small holes on a new sketch and extrude them.
Lab Exercise 14-2
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 14-2 Inventor Course Inches English-Modules Part (in).ipt Zinc N/A
Step 1
Project the Center Point onto the Base plane.
Step 2
Note the location of X0Y0Z0. Draw the Base sketch and revolve it create the Base model of the object shown below. Revolve it by using a centerline. (Figure Step 2A, 2B, 2C, 2D, and 2E)
Step 3
Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches.
Step 4
Apply the colour shown above. (Figure Step 4A and 4B)
Step 5
Add the four small holes and the key on new sketches and extrude them. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/03%3A_Part_3/3.03%3A_Module_14_Revolving.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. 1 Describe fillet and chamfer features.
2. Apply the FILLET and CHAMFER commands to create fillets and chamfers on solid models.
Fillets
A fillet is a tangent arc. A fillet is simply an arc which is tangent at both ends. It can be tangent to two lines, a line and an arc, or two arcs. Technically, it is a fillet when material is added to the object model and a round is when material is removed from the object. See Figure 15-1 and 15-2. Most CAD systems, including Inventor, use the term fillet for both.
There are two basic methods of inserting fillets in Inventor. In this module, inserting the fillets after the solid model is created will be taught. They are called features. In the Inventor Advanced book, drawing fillets on the 2D sketch will be taught. It is always better to insert the fillets as features since that makes them much easier to edit after the solid model is created.
Geometry Lesson Tangency – Part 1
A point of tangency is the theoretical point where a line joins an arc or where two arcs join each other making a smooth transition. A line tangent to a circle passes the circle and touches it on only one point on the circle. The point where they touch is called the point of tangency. See Figure 15-3.
Inventor Command: FILLET
The FILLET command is used to insert a fillet feature on a solid model.
Shortcut: F
WORK ALONG: Creating Models With Fillet Features
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Enter the NEW command to start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 15-1. (Figure Step 3A and 3B)
Step 4
Draw the Base sketch on the Front view. Ensure that it is fully constrained. Extrude the sketch to create the Base model. (Figure Step 4A and 4B)
Step 5
Enter the FILLET command and in the Fillet dialogue box, click the radius to edit it. Change the radius to 1.50. (Figure Step 5)
Step 6
Click the Pencil icon to change to the Arrow icon. When the Plus icon appears beside the cursor, select the top left corner of the model. (Figure Step 6A and 6B)
USER TIP: Another reason that it is best to create fillets on the solid model rather than on the skech is that you can then insert them as the last feature to complete the model. The reason that this is important is once the fillet is created the corners are lost on the model. Without the corners, there is nothing to measure from when placing geometry.
Step 7
Insert the same fillet on the opposite side of the model. (Figure Step 7)
Step 8
Start a new sketch and enter the CENTER POINT CIRCLE command. Right click the mouse. In the Right-click menu, select Center. Select the arc and draw a 1 inch Diam circle. Dimension and extrude it.(Figure Step 8A, 8B, 8C, and 8D)
MUST KNOW: A fillet is a tangent arc. A fillet is simply an arc that is tangent at both ends. It can be tangent to two lines, a line and an arc, or two arcs but it must be tangent at both ends. Technically, a fillet is when material is added to the object. It is called a round when material is removed from the object.
Step 9
Start a new sketch. On it, draw and dimension the slot and extrude it. (Figure Step 9A and 9B)
Step 10
Using what you just learned, insert the 1 inch radius fillets. (Figure Step 10)
Step 11
Insert the fillets as shown on the figures. Ensure that you set the correct radius for each fillet. (Figure Step 11A and 11B)
Step 12
Enter the FILLET command and in the Fillet dialogue box, set the Radius to 0.0875. Set the Select mode to Loop and select the edge as shown in the figure. (Figure Step 12)
Step 13
To complete the model, change the colour to: Chrome – Polished Black. (Figure Step 13)
Step 14
Save and close the file.
USER TIP: Inventor allows two methods of inserting fillets and chamfers. The first method is to create the solid model using extrude or revolution just as you have being doing to this point in the course and then insert the fillets on the solid model.The second method is drawing the fillets in the 2D sketch and they will be created when the sketch is extruded or revolved. The first method is the BEST method and should be used whenever possible. One reason that it is the best method is it allows you to decide the order of filleting. This is especially important where two or more fillets meet or intersect on the model. This is the method you will be using in this module.
Chamfers
A chamferis similar to a fillet except instead of an arc being inserted, it inserts an inclined line. See Figure 15-4. Figure 15-5 shows a multiview drawing with the chamfers dimensioned. There are two basic methods of inserting chamfers in Inventor, the same as fillets. In this module, you will learn how to insert them as features after the solid model is created as shown in Figure 15-6.
Inventor Command: CHAMFER
The CHAMFER command is used to create a chamfer feature on a solid model.
Shortcut: CTRL+ Shift+K
WORK ALONG: Creating Models with Chamfer Features
Step 1
Open the file: Inventor Lab 13-1.ipt that you created in Module 13.
Step 2
Using the SAVEAS command, save the file with the name: Inventor Workalong 15-2. (Figure Step 2A and 2B)
Step 3
Enter the CHAMFER command. In the Chamfer dialogue box, ensure that the equal side icon and Edges icon are enabled. Set the distance to 1.0. Select the bottom right corner of the model. (Figure Step 3)
Step 4
Set the distance to 0.125 and insert the chamfer on the around the top as shown in the figure. (Figure Step 4)
Step 5
Using what you just learned, insert the fillet and chamfers on the model as shown in the figure. (Figure Step 5)
Step 6
Insert the 0.10 chamfers around the outside as shown in the figure. (Figure Step 6)
Step 7
The completed model should appear as shown in the figure. (Figure Step 7)
Step 8
Save and close the file.
USER TIP: Many commands can be used while you are activity using another command. The ORBIT command is one of them. To increase your drawing speed, you can preform an operation on one side of a model and then, while you are still in the command, press F4 and rotate the model. Then preform the operation on another side. This would have worked well for Step 11 as you could have placed the fillet on the other side of the hole in the same FILLET command.
Key Principles
Key Principles in Module 15
1. A fillet is a tangent arc. A fillet is simply an arc which is tangent at both ends. It can be tangent to two lines, a line and an arc or two arcs.
2. A chamfer is similar to a fillet except instead of an arc being inserted, it creates an inclined line.
3. There are two basic methods of inserting fillets in Inventor. In this module, inserting the fillets after the solid model is created will be taught. They are called features. In the Inventor Advanced Modules, drawing fillets on the 2D sketch will be taught. It is always better to insert the fillets as features since that makes them much easier to draw and edit after the solid model is created.
Lab Exercise 15-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 15-1 Inventor Course mm Metric-Modules Part (mm).ipt Steel – Galvanized N/A
Step 1
Project the Center Point onto the Base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produced the solid model shown in the figures. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A, 2B, and 2C)
Step 3
Insert the fillets and chamfers as features after the model is constructed.
Step 4
Apply the colour shown above.
Lab Exercise 15-2
Time allowed: 30 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 15-2 Inventor Course Inches N/A Aluminum – Polished N/A
Step 1
Open the file: Inventor Lab 14-2.ipt that you created in Module 14.
Step 2
Using the SAVEAS command, save it with the name: Inventor Lab 15-2.
Step 3
Add the fillets and chamfers as features as shown in the figures. (Figure Step 3A, 3B, and 3C) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/03%3A_Part_3/3.04%3A_Module_15_Fillet_and_Chamfer_Features.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a two hour time limit, complete a written exam and a lab exercises.
Competency Tests
The Inventor book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are Completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after you have completed this module.
Multiple Choice Questions
Select the BEST answer.
1. Which on of the following statements is true?
1. Construction objects are drawn with the command CONSTRUCTION.
2. Construction objects will not be used when the sketch is converted into a 3D feature.
3. Construction objects cannot be used to constrain the sketch.
4. Construction objects cannot be used as dimensional constraints.
5. Construction objects will be used when the sketch is converted into a 3D feature.
2. When is it best to place fillets and chamfers on a solid model?
1. The last thing you do to complete the solid.
2. The first thing after the base sketch it is revolved.
3. Before the base model is created.
4. When the sketches are being created.
5. The first thing after the base sketch is extruded.
3. Which snap mode is used to snap to the location where two object cross?
1. On
2. Midpoint
3. Intersection
4. Point
5. Center
4. Which one of the following function keys, when pressed, enables the display of the constraint icons?
1. F2
2. F4
3. F6
4. F8
5. F10
5. What two commands are used to create a solid model?
1. REVOLVE AND OFFSET
2. EXTRUDE and REVOLVE
3. EXTRUDE and FILLET
4. PROJECT and SOLID
5. EXTRUDE and MODEL
6. Which key or keys, when pressed while you are selecting objects, will allow you to select more then one object in the selection set?
1. Only TAB
2. Either ALT or SHIFT
3. Either CTRL or ALT
4. Either TAB or CTRL
5. Either CTRL or SHIFT.
7. What does the REVOLVE command do when it finds a centerline in the base sketch it is revolving?
1. It automatically uses the centerline as the axis of revolution.
2. It prompts you to select the axis of revolution.
3. It extrudes the base sketch using it as the centre.
4. It ignores the centerline.
5. It allows you to select another axis as the axis of revolution.
8. Which snap mode is used when you want to snap to the centre of a line?
1. On
2. Midpoint
3. Intersection
4. Point
5. Center
9. Which geometrical constraint is used to make 4 circles all the same diameter when only one of them is dimensioned?
1. Tangent
2. Concentric
3. Coincident
4. Center
5. Equal
10. What one of the following is used to change the properties of a selected object from a drawing object to a construction object?
1. Construction menu
2. Construction icon
3. Construction line
4. Construction circle
5. Construction object
Lab Exercise 16-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 16-1 Inventor Course Inches English-Modules Part (in).ipt Chrome – Polished Blue N/A
Step 1
Note the location of X0Y0Z0. Draw the necessary sketches and revolve or extrude them to produce the 3D model. (Figure Step 1)
Step 2
Draw the base sketch on the Front view. (Figure Step 2)
Step 3
Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. Ensure that all objects, on all sketches, display purple on a black background.
Step 4
Create the fillets and chamfers after the solid model is totally constructed.
Step 5
Apply the colour shown. (Figure Step 5A, 5B, and 5C)
Lab Exercise 16-2
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 16-2 Inventor Course Millimeters Metric-Modules Part (mm).ipt Silicon Nitrite – Polished N/A
Step 1
Note the location of X0Y0Z0. Draw the base sketch on the Right Side view and revolve it to create the base model. (Figure Step 1A, 1B, 1C, and 1D)
Step 2
Draw the necessary sketches and extrude them to complete the model.
Step 3
Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. Ensure that all objects, on all sketches, display purple on a black background.
Step 4
Create the fillets after the solid model is totally constructed.
Step 5
Apply the colour shown. (Figure Step 5A and 5B) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/03%3A_Part_3/3.05%3A_Module_16_Competency_Test_No.3_Open_Book.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe drawing inclined lines, aligned and angular dimensions, loops, trimming, and extending.
2. Apply the GENERAL DIMENSIONS command to insert aligned and angular dimensions on a sketch.
3. Apply the TRIM and EXTEND commands to trim and extend objects in a sketch.
Drafting Lesson: Auxiliary Views
When a model has an inclined side, its plane is not parallel to the horizontal and vertical sides of the glass box. If the inclined view is drawn in one of the predefined views in a multiview drawing, some or all parts of the object will not be their true size and shape. To correct this, an auxiliary view is drawn instead of a predefined view. An auxiliary view is a view looking perpendicular to the inclined plane as shown in Figure 17-1.
Drafting Lesson: Broken Views and Break Lines
To simplify or speed up drawing some of the views of a multiview drawing are only partially drawn. In these cases, the cutoff (sometimes called the broken) portion of the view is not required for the reader to visualize the object. Auxiliary views are frequently cutoff. When a view is cutoff, a break line is drawn to indicate where the view was broken as shown in Figure 17-2. A short break line and a long break line are drawn differently as show in Figure 17-2.
Inventor Command: TRIM
The TRIM command is used to trim a portion of an existing line or arc. The object to be trimmed must intersect an existing object. If it does not intersect an object, the complete object will be deleted instead of being trimmed.
Shortcut: X
Inventor Command: EXTEND
The TRIM command is used to trim a portion of an existing line or arc. The object to be trimmed must intersect an existing object. If it does not intersect an object, the complete object will be deleted instead of being trimmed.
Shortcut: X
Drawing and Dimensioning Inclined Lines
Drawing and dimensioning inclined lines in sketches is a simple operation in Inventor compared to most CAD systems. The reason for this is that you can guess at the angle when drawing the inclined line rather then entering the exact number of degrees. After the sketch is complete, the angle is dimensioned using the exact angle and Inventor will adjust the sketch to match.
Aligned Dimensions
An aligned dimension is a dimension measuring the true length of a line or the true distance between two points. See Figure 17-3. The extension lines will be perpendicular and the dimension line will be parallel to the line or an imaginary line between two points.
Placing an Aligned Dimension
To place an aligned dimension, enter the GENERAL DIMENSION command or the shortcut D and regardless if you are selecting a line, two points, or two lines to dimension, the same Aligned dimension icon will display as shown in Figures 17-4 and Figure 17-5.
Angular Dimensions
An angular dimension is a dimension measuring the angle between two lines or the angle between the imaginary lines between three points. See Figure 17-6. The lines cannot be parallel to each other.
Placing an Angular Dimension
To place an angular dimension, enter the GENERAL DIMENSION command or the shortcut D and either select two lines or three points to place the angular dimension between.
The Two-Line Method
Select the first line. It will change colour. Move the cursor onto the second line and without selecting it, note how it changes colour. The Angular Dimension icon will display as shown in Figure 17-7. Select the second line. Drag the dimension to locate it. See Figure 17-8
The Three-Point Method
Select the first two points and move the cursor onto the third point as shown in Figure 17-9. The second point MUST be the vertex of the angle. The Angular Dimension icon will display as shown in Figure 17-9. Select the third point and drag the angular dimension to the desired location. See Figure 17-10.
WORK ALONG: Drawing Models that Contain Inclined Lines
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 17-1. (Figure Step 3A, 3B, and 3C)
Step 4
Start the Base sketch on the Front or XZ plane.
Step 5
Project the Center Point onto the sketch.
Step 6
Draw the three top lines of the Front view and dimension them. Ensure that the sketch is fully constrained. (Figure Step 6)
Step 7
Enter the OFFSET command. When prompted, select the top line. (Figure Step 7)
Step 8
Right click the mouse and in the Right-click menu, select Continue. Move the cursor down about 0.5 inches. The offset line will drag with it. Click to select the location. (Figure Step 8)
Step 9
Do the same for the other two lines. (Figure Step 9)
Step 10
Enter the TRIM command. When prompted, select the overlapping end of the lines on the top intersection. (Figure Step 10A and 10B)
Step 11
Enter the EXTEND command and extend the lines at the bottom intersection by selecting each of them. (Figure Step 11A and 11B)
MUST KNOW: When inserting an angular dimension, only one dimension can be placed at a time even though there is a choice of placing the dimension in four different locations and two different angles. The figure on the right shows the four different angular dimension locations and the two different angles that can be inserted.
Step 12
Add three dimensions for the 0.5 thickness. The sketch should be fully constrained. (Figure Step 12)
Step 13
Press F6 to return to Home view.
Step 14
Extrude the sketch. (Figure Step 14)
Step 15
Start a new sketch on the top plane. Draw three lines and add the dimensions to fully constrain the sketch. (Figure Step 15)
Step 16
Extrude the sketch using the cut option. (Figure Step 16)
Step 17
Start a new sketch on the inclined plane. Draw three construction lines and dimension them to locate the centre of the circles. Ensure that the lines are fully constrained. (Figure Step 17)
Step 18
Insert two circles locating their centers at the intersection of the construction lines. Dimension only one of them and then apply the Equal constrain to the other circle. (Figure Step 18)
Step 19
Draw a line from one circle to the other. Don’t worry about constraining them tangent at this time. Ensure that the Snap On icon appears when you select the endpoint of the lines. (Figure 19A and 19B)
Step 20
In the right-click menu, select Create Constrain – Tangent. (Figure Step 20).
Step 21
Apply the Tangent constraint between the circle and the line. Repeat with the other circle. (Figure Step 21A and 21B)
Step 22
Trim the circles. This will take four steps. (Figure Step 22)
Step 23
Extrude the sketch. (Figure Step 23)
Step 24
Draw a 2D Sketch on the bottom plane. Using what you just learned, ensure that you constrain the lines tangent to the circles and then trim. (Figure Step 24A and 24B)
Step 25
Extrude the sketch. (Figure Step 25)
Step 26
Insert the fillets and change to the color: Orange to complete the solid model. (Figure Step 26)
Step 27
Save and close the part file.
USER TIP: When inserting an aligned dimension and the Linear dimension icon displays, as shown in the figure immediate right, rather then the Aligned dimension icon, you can change that and force Inventor to place an aligned dimension. Right-click the mouse while the icon is displayed. In the Right-click menu, select Aligned as shown in the figure far right. This will also work in reverse. If the Aligned dimension icon displays, you can instruct Inventor to place a linear dimension either horizontal or vertical.
USER TIP: The TRIM command can be used to completely delete an object rather then just trimming it. If the object to be deleted does not intersect another object, simply press X and select the object to be deleted. If it intersects another object, it will take you more picks to delete it, but, it is still possible. The reason that it is best to use the TRIM command rather then the DELETE command to delete objects is the fact that TRIM has a shortcut (X) while the DELETE command does not have a shortcut. Entering a shortcut on the keyboard is faster then clicking an icon.
MUST KNOW: When offsetting most objects, the offset object can be geometrically constrained to the existing object. If the angle of the object that was offset is modified or the object is moved, the object that was offset will maintain its position in relation to the offset object. In the Right-click menu, during the OFFSET command, the Constrain Offset can be enabled or disabled as required. See the figure on the right.
Key Principles
Key Principles in Module 17
1. You can guess at the angle when drawing inclined lines rather then entering the exact number of degrees. After the sketch is complete, the angles are dimensioned using the exact angle and Inventor will adjust the sketch to match.
2. The TRIM command is used to trim a portion of an existing line or arc. The object to be trimmed must intersect an existing object. If it does not intersect an object, the complete object will be deleted instead of being trimmed.
3. The EXTEND command is used to extend the length of an existing line or arc.
Lab Exercise 17-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab 17-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Beige N/A
Step 1
Project the Center Point onto the base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude or revolve them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3)
Step 4
Create all fillets after the solid model is totally constructed.
Lab Exercise 17-2
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab 17-2 Inventor Course Inches English-Modules Part (in).ipt Nickle N/A
Step 1
Project the Center Point onto the base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude or revolve them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3)
Step 4
Create all fillets after the solid model is totally constructed. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/04%3A_Part_4/4.01%3A_Module_17_Angles.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how to select objects using windows and crossing windows.
2. Describe and apply the THREE POINT ARC, TWO POINT RECTANGLE, and COPY commands.
Methods of Selecting Objects
Selecting Objects
Up to this point in the book, the only way that has been shown how to select objects was to pick them, one at a time. A quicker and more efficient method of selecting multiple objects is to use either a window or a crossing window. Study Figure 18-1 and start using windows and crossing windows when selecting multiple objects in both Sketch or Model mode.
Inventor Command: THREE POINT ARC
The THREE POINT ARC command is used to draw an arc by selecting the two endpoints of the arc and a third point anywhere on the circumference of the arc.
Shortcut: none
Inventor Command: TWO POINT RECTANGLE
The TWO POINT RECTANGLE command is used to draw a rectangle or a square by selecting two points of its opposite corners.
Shortcut: none
Inventor Command: COPY
The COPY command is used in Sketch mode to copy 2D geometry from one XY location to another.
Shortcut: none
WORK ALONG: Drawing a Solid Model with Arcs and Rectangles
Step 1
Check the current project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command, start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 18-1. (Figure Step 3A, 3B, 3C, and 3D)
Step 4
Start the Base sketch on the Front or XZ plane. Project the Center Point onto the sketch.
Step 5
Draw the four outside lines of the Base sketch. (Figure Step 5)
Step 6
Offset all four lines as shown in the figure. (Figure Step 6)
Step 7
Trim and dimension the sketch ensuring that it is totally constrained. (Figure Step 7)
Step 8
Press F6 to change the view to the Home view. All of the lines in the sketch should appear purple. Extrude the sketch. (Figure Step 8)
Sketching Without the Grid
Up to this point in the Inventor book, the grid display has been enabled in Sketch mode. To the more experienced operator, grid display can be disabled in Sketch mode. On some sketches, it is sometimes easier to draw without the grid getting in the way.
Step 9
Start a new sketch on the right side face as shown in the figure. (Figure Step 9)
Step 10
Using what you already learned, open the Application Options dialogue box.
Step 11
Enable the Sketch tab.
Step 12
In the Display area, disable Grid Lines. (Figure Step 12)
Step 13
Draw a construction line 0.5 inches below the top edge and dimension it. Ensure that it is fully constrained. (Figure Step 13)
Step 14
Click the THREE POINT ARC command. Snap the first point to one end of the construction line, snap the second point to the other end of the construction line. For the third point, snap it to the midpoint of the top edge. (Figure Step 14A, 14B, and 14C)
Step 15
Using the CREATE CONSTRAIN command, apply the Tangent constraint to the arc and the top edge. This should fully constrain the sketch. (Figure Step 15)
Step 16
Extrude the sketch. (Figure Step 16A and 16B)
Step 17
Using what you just learned, start a new sketch on the top of the model. On it, draw three construction lines and a three point arc. Ensure that the sketch is fully constrained. Extrude the sketch. (Figure Step 17A and 17B)
Step 18
Start a new sketch on the lower plane. (Figure Step 18)
Step 19
On the sketch, using the TWO POINT RECTANGLE command, draw a rectangle by selecting two opposite corners. Guess at the location and size. (Figure Step 19)
Step 20
Insert four dimensions, one from each edge. Check to ensure that the sketch is fully constrained and extrude it. (Figure Step 20A and 20B)
Step 21
Start a new sketch on the back plane and place a construction line as shown in the figure. Do not offset the edge. Ensure that you constrain the line perpendicular to the bottom or top edge. You can guess at the start point and the length of the line. (Figure Step 21)
Step 22
Change the property of the line to a construction line. Insert one circle at the each end of the line. Snap to the end of the line to locate the centre of the circles. (Figure Step 22)
Step 23
Using what you learned already, dimension one of the circles and then create an Equal constraint for the other one. Draw lines on either side of the circle. Ensure that you snap the end of the lines onto the circles. Constrain the lines to the circle with the Tangent constraint. Trim the circles. (Figure Step 23A, 23B, and 23C)
Step 24
Draw a construction line from the end of the construction line at the top circle, constraining it perpendicular to one of the vertical lines. Draw it approximately 1 inch long. (Figure Step 24)
Step 25
Click the COPY command and select the two lines and the arcs as shown in the figure. Ensure that the Select icon is enabled. (Figure Step 25)
Step 26
Enable the From icon and select the end of the construction line for the From location. (Figure Step 26)
Step 27
Enable the To icon and select the other end of the construction line for the To location. (Figure Step 27)
Step 28
If you get the warning message, click Yes.
Step 29
Dimension the sketch until it is fully constrained. (Figure Step 29)
Step 30
Return to Model mode and extrude the slots. Extrude them 0.25 inches deep. (Figure Step 30)
Step 31
Start a new sketch on the bottom of the extruded slots. Enter the OFFSET command and right-click one of the arcs. In the Right-click menu, enable Loop Select. Select the other arc and the lines to complete the loop. (Figure Step 31A and 31B)
Step 32
Offset the slot towards the inside. Guess at the offset distance. (Figure Step 32)
Step 33
Dimension the offset. (Figure Step 33)
Step 34
Extrude the slot To Next. (Figure Step 34)
Step 35
Redo Step 31 to 34 on the other slot to complete the solid model.
Step 36
Set the colour to: Dark Red. (Figure Step 36)
Step 37
Save and close the file.
MUST KNOW: A window selects all of the objects that are totally inside of it defined by two user picks. A window always appears as a solid line and is created by picking the first point on the left and moving right to pick the second point.A crossing window selects all of the objects that are totally inside and the ones that cross it defined by two user picks. A crossing Window always appear as dashed lines and is created by picking the first point on the right and moving left to select the second point.
To select a window or crossing window, select the first point by moving the cursor to the desired location and press the left mouse button down. While holding it down, move to the cursor to second desired location and release the mouse button.
Key Principles
Key Principles in Module 18
1. A window appears as a solid rectangle selecting only the objects totally inside the window. A crossing window appears as a dashed rectangle selecting all of the objects that it crosses and the ones that are totally inside the crossing window.
Lab Exercise 18-1
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab 18-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Zinc N/A
Step 1
Project the Center Point onto the base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude or revolve them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 2A, 2B, 2C, and 2D)
Step 3
Apply the colour shown above. (Figure Step 3A and 3B)
Lab Exercise 18-2
Time allowed: 60 minutes.
Part Name Project Units Template Color Material
Inventor Lab 18-2 Inventor Course Inches English-Modules Part (in).ipt Galvanized (texture) N/A
Step 1
Project the Center Point onto the base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude or revolve them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 2A and 2B)
Step 3
Apply the colour shown above. (Figure Step 3A and 3B)
Step 4
Create all fillets after the solid model is totally constructed. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/04%3A_Part_4/4.02%3A_Module_18_Editing_Geometry.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe and apply the POLYGON, TANGENT CIRCLE, and THREAD commands.
2. Describe work features including Work Points, Work Axes, and Work Planes and explain how they are used in model construction.
3. Describe and apply the WORK POINT, WORK AXIS, and WORK PLANE commands.
Geometry Lesson: Regular Polygons
A polygon is defined as any plane figure bounded by straight lines. A regular polygon is a polygon that has equal angles, equal sides and can be inscribed in or circumscribed around a circle. The first eight regular polygons are shown in Figure 19-1.
Any regular polygon can be inscribed in or circumscribed around a circle as shown, using a hexagon, in Figure 19-2.
It is important to understand and know the geometry involved to construct a triangle, square, hexagon, and octagon as shown in Figure 19-3. Study each one and try to understand how they are constructed and the angles used to construct them.
Inventor Command: POLYGON
The POLYGON command is used to draw a regular polygon on a 2D sketch. You can select the number of sides and choose between either an inscribed or a circumscribed polygon.
Shortcut: none
Inventor Command: TANGENT CIRCLE
The TANGENT CIRCLE command is used to draw a circle tangent to three lines.
Shortcut: none
Inventor Command: AUTO DIMENSION
The AUTO DIMENSION command is used to add dimensions or constrains automatically to fully constrain a sketch.
Shortcut: none
Drawing Threads
The THREAD command is used to draw exterior threads or interior threads on a 3D solid model. See Figure 19-4 The threads created using the THREAD command are not actual threads constructed on the model. They are simply a graphical representation of the threads. A real life solid model created from the Inventor part would not be threaded. Actual threads can be created but this is a much more advanced feature that is taught in the Inventor Advanced book. The thread specifications can be applied to the thread in the sketch and then be used when creating the working drawing of the part.
Inventor Command: THREAD
The THREAD command is used to draw a graphical representation of an outside or inside diameter thread. The thread specifications can also added to the thread properties.
Shortcut: none
WORK ALONG: Drawing Polygons and Threads – Part 1
Step 1
Using the NEW command start a new part file using the template: English-Modules Part (in).ipt.
Step 2
Save the file with the name: Inventor Workalong 19-1. (Figure Step 2A, 2B, and 2C)
Step 3
Draw the Base sketch on the Top or XY plane.
Step 4
Project the Center Point onto the Base sketch.
Step 5
Enter the POLYGON command and set the number of sides to 6. (Figure Step 5)
Step 6
Enable the Circumscribed Polygon icon. Snap to the Center Point for the centre and select a radius of approximately 0.75 inches. (Figure Step 6)
Step 7
Add the dimension from the Center Point to the left line. (Figure Step 7)
Step 8
Enter the AUTO DIMENSION command. Note that one dimension or constraint is required to fully constrain the sketch. Click Apply. (Figure Step 8A, 8B, and 8C
Step 9
Extrude the hexagon in the negative Z direction. (Figure Step 9)
Step 10
Start a new sketch on the bottom side of the Base model. Enter the TANGENT CIRCLE command. When prompted, select any three edges. (Figure Step 10)
Step 11
Extrude the circle 0.016 inches. Ensure that you enable the Join icon and extrude it away from the bolt head. (Figure Step 11)
Step 12
Start a new sketch on the extruded circle. Draw and dimension a 1 inch circle using the centre of the circle to snap to. Extrude the circle 3 inches. (Figure Step 12A and 12B)
Step 13
Using the CHAMFER command, chamfer the bottom of the bolt. (Figure Step 13)
Step 14
Enter the THREAD command. Enable the Location tab and set the Length to 1.5 and then select the cylinder as the face to thread. Do not close the dialogue box. (Figure Step 14)
Step 15
Enable the Specification tab. Set the thread specifications as shown in the figure. Click OK to execute the command. (Figure Step 15A and 15B)
Step 16
Change the view to the Home view and change the colour to: Metal-Brass. (Figure Step 16)
Step 17
Save and close the file.
MUST KNOW: The threads created by the THREAD command are not actual threads constructed on the model. They are simply a graphical representation of the threads. A real life solid model created from the Inventor part file would not be threaded.
WORK ALONG: Drawing Polygons and Threads – Part 2
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 19-2.
Step 4
Using what you learned in the last workalong, construct the nut shown in the multiview drawing. (Figure Step 4A and 4B)
Step 5
Change the colour to: Metal-Brass. (Figure Step 5A and 5B)
Work Features
Work Features consists of points, axes, and planes that can be inserted on a solid model or in Model space. They are used as a construction aids to draw the model. You can insert them when existing geometry cannot be used to add geometry. The three work features available in Inventor are the work point, the work axis, and the work plane. See Figure 19-5. This module is an introduction to work features only and will teach the user how to create and use them in part modeling. They are also used in assemblies.
Work Points
A Work Point is a parametric construction point or a single XYZ location that is inserted and then used as a work feature. Once a Work Point is inserted on the model, it can be projected onto part faces, linear edges, or onto an arc or circle using the PROJECT GEOMETRY command. Work Points can also be constrained to the centre points of arcs, circles, and ellipses. In this module, inserting Work Points on the model or in 3D space will be taught.
Work Axes
A Work Axis is a parametric construction line or two XYZ locations joined by a line that is inserted and then used as a work feature. Even though a Work Axis appears as a specified length, as far as Inventor is concerned, it is infinite in length and can be expanded to any length required.
Use Work Axes when creating models to mark symmetry lines, centre lines, or distances between revolved feature axes. Work Axes can be used along the symmetry lines of circular features such as cylinders, shafts, or holes. They can also be created as a work axis on a linear edge, a sketch line, or a 3D sketch line.
Work Planes
A Work Plane is parametric construction plane or four XYZ locations joined by lines inserted on the model or in model space and then used as a work feature. Even though a Work Plane appears as a rectangular plane of a given size, it is actually infinite in size and can be expanded to any size required.
Work Planes can be placed at any orientation in space, offset from existing faces, or rotated around an axis or edge. A work plane can be used as a sketch plane and dimensioned or constrained to other features or components. Each work plane has its own internal coordinate system. The order in which geometry is selected determines the origin and positive directions of the coordinate system axes.
Inventor Command: WORK POINT
The WORK POINT command is used to insert a Work Point on the model or in Model space.
Shortcut: . (period)
Inventor Command: WORK AXIS
The WORK AXIS command is used to insert a Work Axis on the model or in Model space.
Shortcut: / (forward slash)
Inventor Command: WORK PLANE
The WORK PLANE command is used to insert a Work Plane on the model or in Model space.
Shortcut:] (right bracket)
WORK ALONG: Creating Work Features
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command start a new part file using the template: English-Modules Part (in).ipt.
Step 3
Save the file with the name: Inventor Workalong 19-3.
Step 4
Create the solid model shown in the figures. (Figure Step 4A and 4B)
Step 5
Insert a Work Point at the apparent intersection of two edges. Click the WORK POINT command and then Intersection of Two Lines. Select the edges shown in the figure. Note how they highlight and extend. (Figure Step 5A, 5B, and 5C)
Step 6
Insert a Work Point at the intersection of three planes. Click the WORK POINT command and then Intersection of Three Planes. Select the planes shown in the figures. (Figure Step 6A, 6B, 6C, 6D, and 6E)
Step 7
To insert a Work Point at the midpoint of an edge. Click the WORK POINT command and then On Vertex, Sketch point, or Midpoint. Snap to the midpoint of the edge shown in the figure. The midpoint will highlight with a yellow work point symbol. Select it when it appears. (Figure Step 7A, 7B, and 7C)
Step 8
Work Features will display as items in the Browser bar. Note the three Work Points that you just inserted. The visibility of Work Features can be enabled or disabled in the Right-click menu. (Figure 8A and 8B)
Step 9
Insert a Work Axis on the centerline of the cylinder. Enter the WORK AXIS command and then Through Center of Circular or Elliptical Edge. Select the cylinder as shown in the figure. Note how the cylinder highlights. The axis will appear as a colored line. (Figure Step 9A, 9B, and 9C)
Step 10
Insert a Work Axis between two Work Points. Enter the WORK AXIS command and then Through Two Points. Select the Work Points on the front edge and the back corner. (Figure Step 10A, 10B, 10C, and 10D)
Step 11
Insert a Work Axis at the intersection of two non-parallel faces. Enter the WORK AXIS command and then Intersection of Two Planes. Select the face on the left side and then the face on the right side. The Work Axis will appear at the apparent intersection of the two faces. (Figure Step 11A, 11B, 11C, and 11D)
Step 12
Work Features will display as items in the Browser bar. Note the three Work Axes that you just inserted. (Figure Step 12)
Step 13
Insert a Work Plane from an existing face and through a Work Axis at a specified angle. Enter the WORK PLANE command and then Plane. Select the face on the right side of the model and then select the Work Axis at the centre of the cylinder. Enter the angle between the new Work Plane and the face. In this case, 90 degrees or perpendicular. (Figure Step 13A, 13B, 13C, and 13D)
Step 14
Insert an offset Work Plane. Enter the WORK PLANE command and then Offset from Plane. Select the face on the right side. Hold down the left mouse button and drag the plane into the model. The Offset dialogue box will display. Enter the offset distance of -1.25 inches. (Figure Step 14A, 14B, and 14C)
Step 15
Move the cursor to the edge of the newly inserted work plane and when the double arrow icon appears, press and hold down the left mouse button. While holding it down, drag it to enlarge the plane. Do this for all four corners. (Figure Step 15A and 15B)
Step 16
Insert a Work Plane on a work axis and at an angle to an existing plane. Enter the WORK PLANE command and then Plane. Select the Work Axis shown in the figure. Select the bottom plane next and enter the angle of 90 degrees. (Figure Step 16A, 16B, 16C, 16D, and 16E)
Step 17
The Browser bar should now appear as shown in the figure. (Figure Step 17)
Step 18
Disable the visibility of all Work Features. Your solid model should appear as shown in the figure. (Figure Step 18)
Step 19
Using the offset method, insert a Work Plane -2.25 inches from the right side face. Expand the size of the Work Plane. Start a new sketch on the Work Plane. (Figure Step 19A and 19B)
Step 20
Enter the TWO POINT RECTANGLE command and right click the mouse. Ensure that AutoProject is enabled. Draw a rectangle by snapping to the bottom right corner. Dimension the square and ensure it is fully constrained. Extrude the sketch. (Figure Step 20A, 20B, 20C, and 20D)
Step 21
Start a new sketch and draw two lines. Dimension and extrude it. (Figure Step 21A and 21B)
Step 22
Insert a Work Plane -0.375 inches in from the front face. (Figure Step 22)
Step 23
Draw a triangle and insert two dimensions to fully constrain it. (Figure Step 23)
Step 24
Extrude the sketch 0.125 inches in both directions to complete the part. (Figure Step 24)
Step 25
Disable the visibility of all Work Features. The completed solid model should appear as shown in the figure. (Figure Step 25)
Step 26
Change to the Home view. (Figure Step 26)
Step 27
Save and close the part.
Key Principles
Key Principles in Module 19
1. The POLYGON command is used to draw a regular polygon on a 2D sketch. You can select the number of sides and choose between either an inscribed or a circumscribed polygon.
2. The threads created by the THREAD command are not actual threads constructed on the model. They are simply a graphical representation of the threads.
3. The TANGENT CIRCLE command is used to draw a circle tangent to three lines.
4. The AUTO DIMENSION command is used to add dimensions or constrains automatically to fully constrain a sketch.
5. The three Work Features available in Inventor are the Work Point, the Work Axis, and the Work Plane.
6. A Work Point is a parametric construction point or a single XYZ location that is inserted and then used as a Work Feature.
7. A Work Axis is a parametric construction line or two XYZ locations joined by a line that is inserted and then used as a Work Feature.
8. A Work Plane is parametric construction plane or four XYZ locations joined by lines inserted on the model or Model space and then used as a Work Feature.
Lab Exercise 19-1
Time allowed: 90 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 19-1 Inventor Course Millimeters Metric – Modules Part (mm).ipt Chrome – Black Polished N/A
Step 1
Draw the Base sketch on the Front view.
Step 2
Project the Center Point onto the Base plane.
Step 3
Note the location of X0Y0Z0. Draw the necessary sketches and EXTRUDE them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 3A, 3B, 3C, 3D, and 3E)
Step 4
Create the fillets and chamfers after the model is totally constructed.
Step 5
Apply the colour shown above.
Lab Exercise 19-2
Time allowed: 90 minutes.
Part Name Project Units Template Color Material
Inventor Lab Lab 19-2 Inventor Course Millimeters Metric – Modules Part (mm).ipt Chrome – Black Polished N/A
Step 1
Draw the Base sketch on the Right Side view.
Step 2
Project the Center Point onto the Base plane.
Step 3
Note the location of X0Y0Z0. Draw the same model you just drew in Lab Exercise 19-1. In this exercise, REVOLVE the Base sketch and then add sketches and extrude them to complete the model. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 3A, 3B, 3C, and 3D)
Step 4
Create the fillets and chamfers after the model is totally constructed.
Step 5
Apply the colour shown above.
Lab Exercise 19-3
Time allowed: 90 minutes.
Part Name: Inventor Lab 19-3 Project: Inventor Course Units: Millimeters
Template: Metric – Modules Part (mm).ipt Color: Galvanized (texture) Material: N/A
Step 1
Project the Center Point onto the Base sketch.
Step 2
Draw the necessary sketches and extrude or revolve them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. (Figure Step 2A, 2B, 2C, 2D, and 2E)
Step 3
Create the fillets and chamfers after the model is totally constructed.
Step 4
Apply the colour shown above. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/04%3A_Part_4/4.03%3A_Module_19_Work_Features.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe how to edit the dimensions and part features of an existing solid model using the Browser bar to aid you.
2. Describe how to hide and/or suppress features in the solid model.
3. Describe and apply the MEASURE command to measure lengths, loops, angles, or areas of a solid model in either two dimensions or three dimensions.
4. Describe how to set the material and change the colour of faces of the solid model.
5. Describe how to obtain the physical properties of a solid model.
Modifying Solid Models
The ability to modify solid models is as important to the drafter/designer as being able to construct models. Since most parts are modified after the initial design or revised and used in another project, it is very important that you can modify solid models rather then redraw them. The true power of Inventor is its ability to modify a solid and have it conform to the geometrical and dimensional constraints applied to it when it was constructed without having to redraw it. In this module, the basics of modifying solid models is taught. The Inventor Advanced book will cover the more advanced methods of modifying solid models.
Working with the Browser Bar
The Browser bar is used extensively as a tool to assist you when modifying solid models. It displays the work features and the part features for the current part.
Features
Work features are the basic sketching planes (XY, XZ, YZ), the axes (X, Y, Z) and the Center Point as shown in Figure 20-1.Part features are the 3D features added to the solid model in model construction. The part features for the active part are shown in Figure 20-2.
Edges and Faces
Edges are the lines, circles, or arcs located between the planes that form the solid model. Faces are the planes between the edges of the solid. A face can also be circular or cylindrical in shade, for example the hole in the model. Figure 20-3 shows each visible face of a solid model in a different colour.
WORK ALONG: Modifying a Solid Model
Step 1
Open the part file: Inventor Workalong 20-1.ipt. This is one of the parts that you received when you download your book. It should be in the folder: Lab Exercise. (Figure Step 1A and 1B)
Step 2
The Filter icon located at the top of the Browser bar allows you to enable or disable the visibility of the features in the Browser bar. Click the Filter icon. The filter list will display. (Figure Step 2A and 2B)
Step 3
Click Hide Work Features to enable it. The work features are now hidden for the current part. (Figure Step 3A and 3B)
Step 4
Since you want the work features to display most of the time, click the Filter icon again and disable the Hide Work Features. (Figure Step 4)
Step 5
The Part icon is the first icon inside the Browser bar window. It displays the name of the active part. (Figure Step 5)
Step 6
Right-click the part name. In the Right-click menu, click Expand All Children. Note how all the folders and part features will expand to display every feature in the current part. Right click the menu again and this time, click Collapse All Children. (Figure Step 6A, 6B, and 6C)
Step 7
Right-click the part feature Extrusion1. In the Right-click menu, click Show Dimensions. Note how the 2D sketch dimensions and the extrusion dimension will display on the model. (Figure Step 7)
Step 8
Right-click Extrusion1 again. In the Right-click menu, click Edit Sketch. The Graphic window will change to Sketch mode and display the sketch. (Figure Step 8)
Step 9
Double click any dimension in the sketch and the Edit Dimension dialogue box will open as shown in the figure. You could now change the dimension, if required, which in turn will change the size of the model. Close the dialogue box without making any changes and return to Model mode. (Figure Step 9)
Step 10
Right-click Extrusion1. In the right-click menu, click Edit Feature. Since this feature is an extrusion, the Extrude dialogue box will open. If required, the extrude feature could be edited. Click the Cancel button to close it. (Figure Step 10A and 10B)
Step 11
Right-click Extrusion3 as shown in the figure. In the right-click menu, click Find in Window. Note how the extrude on the left side will fully display in the window. This is a handy feature to use when your part is complicated or if you are using a part you are not familiar with. (Figure Step 11)
Step 12
Using what you learned in Steps 8 to 11, edit the sketch in Extrusion1 to match the dimensions shown in the figure. When you are done, click Finish Sketch to return to Model mode and the model will resize to reflect the changes you made to the dimensions. (Figure Step 12)
Step 13
Edit Extrusion1 to change the extrusion depth from 3 inches to 4 inches. Click OK. (Figure Step 13)
Step 14
Edit the dimensions in the sketch for the part feature Extrusion4 to the dimensions shown in the figure. Return to Model mode. (Figure Step 14A and 14B)
Step 15
Since Sketch1 is an unconsumed sketch, it can be deleted. Select it and right click it. In the Right-click menu, select Delete. (Figure Step 15)
Step 16
Expand the children. Change the name of Sketch2 to Base Sketch – Front View. (Figure Step 16A and 16B)
Step 17
Change the names of all the part features and their children to match the names in the figure. Change the name of the part to: Inventor Workalong 20-1 Finished.ipt as shown in the figure. (Figure Step 17)
Step 18
Move the cursor onto the End of Part icon and hold down the left mouse button. When the End of Part has a red rectangle around it, drag it to the location shown in the figure. (Figure Step 18A, 18B, and 18C)
Step 19
Drag the End of Part icon back to the bottom of the part feature list in the Browser bar. (Figure Step 19A and 19B)
Step 20
Using the SAVEAS command, save the file with the name: Inventor Workalong 20-1 Finished. Close the part.
Measuring the Model
Inventor has four commands available to measure distances, angles, loops lengths and areas. They also allow the user to set the units and decimal precision of how it displays the answers. Answers can be accumulated. Measurements can be made in either 3D (Model mode) or 2D (Sketch mode).
Inventor Command: MEASURE DISTANCE, MEASURE ANGLE, MEASURE LOOP, MEASURE AREA
The MEASURE command is used to measure distances, angles, loops lengths and areas. It can be used in model mode or sketch mode. If it is used in Model mode, it measures in 3D and in Sketch mode, it measures in 2D.
Shortcut: None
WORK ALONG: Measuring a Solid Model
Step 1
Open part file: Inventor Workalong 20-1.ipt. (Figure Step 1)
Step 2
Click the MEASURE DISTANCE command. The Measure Distance dialogue box will display as shown in the figure. Move this dialogue box close to your model to make measuring easier. (Figure Step 2).
Step 3
Note that when you are in Measuring mode, the Graphic cursor appears as a ruler icon. The ruler icon indicates that you are measuring in document units. This will be covered in greater detail later in the module. (Figure Step 3)
Step 4
Move the cursor to the bottom left corner of the model and click the left mouse button. Note how it displays a small snap circle indicating that you are snapping to an exact endpoint. (Figure Step 4)
Step 5
When you snap to a location on the model, the XYZ coordinate location will display as shown in the figure. In this case, it is X0Y0Z0 of the model or the Center Point. (Figure Step 5)
Step 6
To clear the Measure Distance dialogue box and start a new measurement, click the small triangle inside the dialogue box. In the pull-down menu, select Restart. (Figure Step 6)
Step 7
Move the cursor to bottom right corner of the right side of the model. Click it to snap to the corner. The XYZ location will display in the dialogue box as shown in the figure. (Figure Step 7)
Step 8
Clear the dialogue box by clicking Restart. Measure the length of an edge. Move the cursor onto the left edge of the right side of the model as shown in the figure. (Figure Step 8)
Step 9
When you click the mouse, the length of the edge will display in the dialogue box. In this case, it is 3 inches long. (Figure Step 9)
Step 10
While the dialogue box is still displaying the length of the edge, click the opposite edge. Note how the dialogue box now displays both the length of the edge and the distance between the edges. A line showing the measured distance will display to show you what is being measured. (Figure Step 10)
Step 11
To measure a three dimensional distance, click the two corners shown in the figure. The 3D dimension between the corners will display as well as the XYZ location of the last corner and the delta XYZ distances. (Figure Step 11A and 11B)
Step 12
Measure the angle between the two edges by clicking the small triangle at the end of the dialogue box. In the pull-down menu, select Measure Angle. Select the two edges. The angle will display graphically and as an exact number in decimal degrees. (Figure Step 12A and 12B)
Step 13
Change the command to Measure Loop. Click the face on the Front view. Note how the complete loop (the perimeter) around the front plane will highlight and the loop distance of 22 inches will display in the dialogue box. (Figure Step 13A and 13B)
Step 14
Measure the area of the right side face by changing the command to Measure Area. Click the face on the right side and the area to be measured will highlight. The area will display in the dialogue box. Since there is a hole in this plane, the area will be measured minus the hole. (Figure Step 14A and 14B)
Step 15
Suppress the hole feature on the right side face so that you can measure the area of the face without subtracting the hole. Right-click the feature in the Browser bar. In the Right-click menu, select Suppress Feature. Note how Extrusion4 is now grayed out. (Figure Step 15)
Step 16
Using what you just learned, measure the area of the right-side minus the hole. After you measure it, unsuppress the hole feature. (Figure Step 16)
Step 17
Click Tools and then click Document Settings. This will open the Document Setting dialogue box for the current part. Do not make any changes at this time. Click Close to close the dialogue box. (Figure Step 17A and 17B)
Step 18
Enter the MEASURE command. Click the small triangle at the end. In the pull-down menu, select Precision and then 5 places. An example of an area measurement with a precision of 5 decimals points is shown in the figure.
Step 19
Change the precision to display All Decimals. A sample of an answer to an area measurement is shown in the figure. (Figure Step 19)
Step 20
Change the precision back to three decimal places. (Figure Step 20)
Step 21
Change the colour to: Aluminum Cast. (Figure Step 21)
Step 22
Save and close the part.
Geometry Lesson: Physical Properties
Mass: the quantity of the matter contained in the solid model. This is determined by multiplying the volume of the solid times the density of the material it is made from. Mass is not dependent on gravity which makes it different but proportional to the weight. Mass is used when considering a measure of a solid’s resistance to inertia.
Volume: The amount of space occupied by the solid model.
Density: The weight of material usually expressed per cubic inch or cubic millimeter. i.e. 21.55^3in or 42.87^3mm
Center of Gravity: Geometrical centre of the solid model. It is also called the centroid. If the density of the solid is uniform, the centre of gravity or centroid is located at the centre of the mass.
Mass = Volume X Density Expressed as lbmass, grams or kg
Area = Length X Width of a 2D plane. Expressed as sq in or sq mm. ie. 10.5^2in or 23.5^2mm
Volume – cubic inches or millimeters. Expressed as cu in or cu mm ie. 120.5^3in or 55.3^3mm
lbmass – pounds
kg – kilograms 1 kg = 1000 grams 1 kg = 2.2 pounds
in – inches
mm – millimeters 1 in = 25.4 mm
Inventor will display answers in scientific notation to control the number of decimals displayed: For Example 1,250,000 = 1.25E+006 (move the decimal 6 places positively)
0.0001 = 1.0E-004 (move the decimal 4 places negatively)
Face Coloring
Sometimes it is helpful to be able to change the colour of a face. This is especially helpful when working with complex parts or to display different textures on a model. For example, this can happen during manufacturing when a part is cast and has machined surfaces. By applying the cast material to the part and then changing the faces of the machined areas to a polished texture/color, the model will appear more realistic.
A face colour overrides the part colour and, if applicable, the feature colour for selected faces. In this module, only faces coloring will be taught. The general rules when changing the colour of faces are:
1. A face colour overrides the part feature colour which in turn overrides the part colour.
2. If the part has been assigned a transparent colour, the face colour you apply will change the colour but it will be transparent.
3. If a thread texture is applied to the feature, a change to the face colour affects the base colour used in the thread texture.
4. If the face colour has been changed and the feature is colored as a pattern, the patterned features will not display the face colour.
Physical Properties
The physical properties of a solid model include the mass, volume, centre of gravity, and inertial properties. Using the physical properties helps you to evaluate how the designed model correlates to its physical counterpart. For example, the weight of a solid model made from different materials could easily be found.
Assigning the Material to the Model
Up to this point in the book, only colour or texture has been assigned to the solid model. In this module, assigning the actual material that the part is made from will be taught.
WORK ALONG: Coloring Faces and Working with Physical Properties
Step 1
Open part file: Inventor Workalong 20-1.ipt. (Figure Step 1)
Step 2
Click the right side face to select it and right click the mouse. In the Right-click menu, select Properties. In the Face Properties dialogue box, select: Blue – Wall Paint – Glossy. (Figure Step 2A, 2B, and 2C)
Step 3
Using what you just learned, change three additional faces as shown in the figure to Green, Orange and Red. (Figure Step 3)
Step 4
Click the View tab. Click the CENTER OF GRAVITY command. Note how the Center of Gravity icon will display located at the centre of gravity or centroid of the model. It also displays the positive X, Y and Z axis. (Figure Step 4A and 4B)
Step 5
Rotate the model so that you can see the location of Center of Gravity icon from a better viewpoint . (Figure Step 5)
Step 6
Disable the display of the Center of Gravity icon.
Step 7
Right-click the part name in the Browser bar. In the Right-click menu, select iProperties. This will open the Properties dialogue box for the current part. (Figure step 7A and 7B)
Step 8
Enable the Physical tab. Note how the material is shown as Default. Pull down the Material list and select: Aluminum 6061. (Figure Step 8)
Step 9
Change the Requested Accuracy to Very High. The Density box displays the density of the material: Aluminum 6061. (Figure Step 9)
Step 10
Using what you learned earlier in the workalong, open the Document Settings dialogue box and in the Units tab, change the Mass to gram. (Figure Step 10)
Step 11
Note how the mass (weight) is now displayed in grams. (Figure Step 11)
Step 12
Change the material to: Cast Steel. Note how the density and the mass change since steel is much denser then aluminum.
Step 13
Change the material back to: Aluminum-6061. Close the Properties dialogue box.
Step 14
Save and close the part.
Key Principles
Key Principles in Module 20
1. The Browser bar is used extensively as a tool to assist you when modifying solid models.
2. Work features are the basic sketching planes (XY, XZ, YZ), the axes (X, Y, Z) and the Center Point. Part features are the 3D features added to the solid model in model construction.
3. Edges are the lines, circles or arcs located between the planes that form the solid model. Faces are the planes between the edges of the solid.
4. Inventor has four commands available to measure distances, angles, loops lengths, and areas. They also allow you to set the units and decimal precision of how it displays the answers. Answers can be accumulated. Measurements can be made in either 3D (Model mode) or 2D (Sketch mode) mode.
Lab Exercise 20-1
Time allowed: 60 minutes.
Part Name: Inventor Lab 20-1 Project: Inventor Course Units: Millimeters
Template: Metric – Modules Part (mm).ipt Color: Aluminum (Cast) Material: Aluminum – 6061
Step 1
Open the part: Inventor Lab 19-3.ipt that you created in Module 19. (Figure Step 1)
Step 2
Save the file as: Inventor Lab 20-1.
Step 3
Change the model colour to: Aluminum (Cast).
Step 4
Expand All the Children in the Browser bar.
Step 5
Edit the Base sketch and change the dimensions of the overall length from 180 to 200 and the overall width from 140 to 175 in the figure. (Figure Step 5)
Step 6
Edit the feature Extrusion1 and change the thickness of the base sketch from 15mm to 20 mm. Return to model mode.
Step 7
Using the next five figures below, change the colors of the machined faces shown to: Aluminum (Polished). (Figure Step 7A, 7B, 7C, 7D, and 7E)
Lab Exercise 20-2
Time allowed: 60 minutes.
Part Name: Inventor Lab 20-2 Project: Inventor Course Units: Inches
Template: N/A Color: Blue Gray (Light) Material: Cast Iron
Step 1
Open part: Inventor Lab 18-2.ipt that you created in Module 18. (Figure Step 1A and 1B)
Step 2
Save the file as: Inventor Lab 20-2.
Step 3
Change the colour to: Blue Gray (Light)
Step 4
Move the End of Part Icon up above the small fillets as shown below. (Figure Step 4)
Step 5
Find the following with a precision of 5 decimal points. (Figure Step 5)
A The XYZ coordinates of corner A.
____________________________
B The distance from corner B to corner C.
____________________________
C The distance from corner B to corner D.
____________________________
D The area of the shaded area the figure. Do NOT include the area of the cylinder. (Figure Step 5D)
____________________________
E The perimeter of the shaded plane. (Figure Step 5E)
____________________________
F The area of the shaded area of the figure WITHOUT the eight small holes. (Figure Step 5F)
____________________________
Step 6
Move the End of Part icon back to bottom.
Step 7
Using the two figures, change the colors of the faces shown to: Blue Pastel. (Figure Step 7A and 7B)
Step 8
Set the material to: Cast Iron and find the following:
A The mass in pounds.
____________________________
B The mass in grams.
____________________________
Step 9
Save and close the part. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/04%3A_Part_4/4.04%3A_Module_20_Modifying_Solid_Models.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a two hour time limit, complete a written exam and a lab exercise.
The Inventor book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are Completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after you have completed this module.
Multiple Choice Questions
Select the BEST answer.
1. When you are selecting objects with a window, which window selects all the objects that are totally inside it and the ones that it crosses?
1. Square Window
2. Crossing Window
3. Extruded Window
4. Rectangular Window
5. Polygon Window
2. What is the name for two or more objects that are connected at their endpoints and then treated as one object in the OFFSET command?
1. Loop
2. Continuous
3. Area
4. Polyloop
5. Window
3. What are the basic sketching planes (XY, XZ, YZ), the three axis (X, Y, Z) and the Center Point called?
1. Work Planes
2. Work Points
3. Work Features
4. Work Sketches
5. Work Axis
4. What is the maximum number of sides that the POLYGON command can draw a regular polygon?
1. 20
2. 100
3. 120
4. 180
5. 256
5. When the graphic cursor appears as a ruler, what units are you measuring in? Select the BEST answer.
1. English Units
2. Document Units
3. System Units
4. Metric Units
5. Actual Units
6. What command is used to extend the length of an existing line or an arc?
1. LENGTHEN
2. EXTEND
3. LINE
4. LENGTH
5. STRETCH
7. What does an aligned dimension measure?
1. The delta X or delta Y distance between two points.
2. The diameter of circle or radius of an arc.
3. The true length of a line or the true distance between two points.
4. The horizontal or vertical distance between two points.
5. The angle between two lines or the angle between the imaginary lines between three points.
8. What best describes the threads created using the THREAD command?
1. Graphical representations of the actual thread.
2. A texture
3. The actual thread.
4. They are enlarged to look better.
5. Center
9. What is a parametric construction plane inserted on the model or in model space called?
1. A Work Plane
2. A Work Point
3. A Work Feature
4. A Work Sketch
5. A Work Model
10. What is an angular dimension measuring?
1. The delta X or delta Y distance between two points.
2. The diameter of circle or radius of an arc.
3. The true length of a line or the true distance between two points.
4. The horizontal or vertical distance between two points.
5. The angle between two lines or the angle between the imaginary lines between three points.
Lab Exercise 21-1
Time allowed: 2 hours.
Part Name Project Units Template Color Material
Inventor Lab 21-1 Inventor Course Millimeters Metric-Modules Part (mm).ipt Machined-Aluminum Aluminum-6061
Step 1
Project the Center Point onto the Base plane.
Step 2
Note the location of X0Y0Z0. Draw the necessary sketches and extrude them to produce the solid model shown below. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. All sketches must be fully constrained. (Figure Step 2A and 2B)
Step 3
Create the fillets and chamfers after the model is totally constructed.
Step 4
Apply the colour shown above. (Figure Step 4)
Step 5
Move the End of Part Icon up above the fillets as shown in the figure. Suppress all of the threaded features. (Figure Step 5)
Step 6
Find the following to a precision of 6 decimal points: (Figure Step 6)
A The XYZ coordinates of corner D.
____________________________
B The length of the edge from corner A to corner B.
____________________________
C The distance from corner A to corner C.
____________________________
D The distance from corner C to corner D.
____________________________
E The angle between the edges B to C and B
____________________________
Step 8
The area of the shaded area of Figure Step 8. Do NOT include the area of features on the plane.
____________________________
Step 9
The perimeter of the shaded plane in Figure Step 9.
____________________________
Step 10
The area of the shaded area of Figure Step 10. The area should include the complete surface without any features.
____________________________
Step 11
Using the three figures below, change the colors of the faces shown to: Aluminum – Polished. (Figure Step 11A, 11B, and 11C)
Step 12
• If you are a student completing this course in a classroom setting, your instructor will give you instructions on what to do after you complete this module.
• If you are an online student doing this course by correspondence, send an email to your instructor with the answers from the measurement questions in this module. For example:
7A The XYZ coordinates of corner D is ___________ .
7B The length of the edge from corner A to corner B is ___________ .
7C The distance from corner A to corner C is ___________ .
7D The distance from corner C to corner D is ___________ .
7E The angle between the edges B to C and B to A is ___________ .
8 The area of the shaded area of Figure Step 8 is ___________ .
9 The perimeter of the shaded plane in Figure Step 9 is ___________ .
10 The area of the shaded area of Figure Step 10 is ___________ .
12A The mass of the solid model in grams is ___________ .
12B The mass of the solid model in pounds is ___________ .
The answers in the email can be given as follows:
7A ___________ .
7B ___________ .
7C ___________ .
7D ___________ .
7E ___________ .
8 ___________ .
9 ___________ .
10 ___________ .
12A ___________ .
12B ___________ . | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/04%3A_Part_4/4.05%3A_Module_21_Competency_Test_No._4_Open_Book.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe an assembly and explain the difference between a top-down and a bottom-up assembly.
2. Describe and apply the SLICE GRAPHICS command.
3. Describe the PLACE COMPONENT and PLACE CONSTRAINT commands and apply them to assemble a series of parts to create an assembled model.
An Assembly File
An assembly file contains the information required to assemble two or more part files to create an assembled model. See Figure 22-1. As the model is assembled, assembly constraints must be assigned so that each part knows how it aligns or fits with the other parts in the assembled model. A part (.ipt) file that has been placed in the assembly can be edited while in the assembly file and the modifications will be saved back to the original part file. On the other hand, if the original part file is modified after the assembly file has being created, the modifications will automatically display in the assembly. An assembly file does not actually contain any of the part files that are placed in the file, it simply contains a reference to them.
A reference is a link back to the part files. The part files that have been placed in an assembly file must be available to Inventor to display them when an assembly file is opened. The current project file keeps track of those links and will automatically keep track of the location of all the part files. If an assembly file is sent to a client or an associate, the part files that were placed in the assembly file must also be included.
Creating an Assembly File
To create an assembly file, use the NEW command and select an assembly template rather than a part template. An assembly file has the extension .iam. IAM is an acronym for Inventor Assembly.
MUST KNOW: An assembly file contains the information required to assemble two or more part files to create the assembled model. An assembly file has the file extension .iam. IAM is an acronym for Inventor Assembly.
Bottom-up vs Top-down
Assembly files can be created using either the bottom-up or the top-down method. A bottom-up assembly is an assembly created from a series of part files that were previously created and saved in their own .ipt file. A top-down assembly is an assembly file where all parts of the assembly are created on the fly. In other word, they are created in the active assembly file, one at a time. They are aligned and constrained in their correct position in relationship to the other parts in the assembled model. Inventor will save each part in its own file with the extension .ipt. In the Inventor book, only the bottom-up method is taught.
The Browser Bar in an Assembly
When an assembly is the active file, the Browser bar will display all of the parts that have been placed in the assembly. If a part in the browser is expanded it will display its children which includes its alignment and constraints to the other parts of the assembled model. See Figure 22-2.
If the same part is placed more then once into the assembly file, the Browser bar will number them accordingly. For example, this may happen if an assembly required two identical bolts. Only one part file is created and named Bolt.ipt. It is then placed into the assembly file twice. The Browser bar would number the bolts parts as follows:
On the first occurrence: Bolt:1
On the second occurrence: Bolt:2
Inventor Command: SLICE GRAPHICS
The SLICE GRAPHICS command is used to slice away the model on the active sketching plane temporarily removing all of the material in front of the sketching plane. The sketching plane must be active before using this command.Shortcut: F7
WORK ALONG: Creating the Parts for an Assembly
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Use the following instructions to complete all parts in this workalong. Create the following parts and ensure that you do the following:
A Each part must be saved in its own .ipt file.
B Project the Center Point onto the Base sketch plane and note the location of X0Y0Z0.
C Draw the necessary sketches and extrude or revolve them to produce the solid model shown. Apply all of the necessary geometrical and dimensional constraints to fully constrain each sketch.
D Apply the colour and material shown.
Step 3
Construct Part A. (Figure Step 3A, 3B, and 3C)
Part: Base
Part Name: Inventor Workalong 22-1A
Template: English-Modules Part (in).ipt
Color: Stainless – Brushed
Material: Stainless Steel
Step 4
Construct Part B. (Figure Step 4A and 4B)
Note: See Steps 3 to 14 if you require help creating this model.
Part: Post
Part Name: Inventor Workalong 22-1B
Template: English-Modules Part (in).ipt
Color: Chrome – Black Polished
Material: Steel
Step 5
Draw the Base model of part 22-1B by extruding circles. Your Base model should appear as shown in the figure. (Figure Step 5)
Step 6
Start a new sketch on the top of the model and draw a construction line from the centre to the edge of the top plane along the Y axis as shown in the figure. Hint: Ensure that you draw the line along the Y axis by snapping to the centre of the circle and to the grid on the Y axis. The length of the line is not important. (Figure Step 6)
Step 7
Insert a Work Plane in the centre of the model using the Perpendicular to a Line method. Enter the WORK PLANE command and move the cursor to the end of the construction line. The Work Plane icon will display as shown in the figure. Click the end of the line when the icon displays. (Figure Step 7)
USER TIP: Before drawing each part, the orientation of the part when it is placed in the future assembly, should be considered. Doing that, will save a lot of time when creating the assembly model since it can be placed without any manipulation.
Step 8
Move the cursor onto the Y axis and it will display as shown in the figure. When the Y axis is displayed, click it and the Work Plane will display as shown. (Figure Step 8A and 8B)
Step 9
Enlarge the Work Plane to extend it past the edges of the model. One way to do this is to use the LOOK AT/VIEW FACE command and change the view so that it is looking perpendicular to the plane as shown in the figure. (Figure Step 9)
Step 10
Start a new sketch on the Work Plane. (Figure 10)
Step 11
Enter the SLICE GRAPHIC command (F7) and the model will display from the sketching plane back. Disable the grid display. It is easier to draw this sketch without the grid. (Figure Step11)
USER TIP: When enlarging the work plane, the cursor must display as the Stretch Move Stretch Cursor (two arrows) as shown. If you Cursor Cursor have trouble changing the cursor from the Move Cursor, zoom in closer and move the cursor onto one of the corners of the plane.
Step 12
Using the PROJECT GEOMETRY command, project the Z axis and the X axis onto the sketching plane. (Figure Step 12A and 12B)
Step 13
Using the OFFSET command, construct offsets to both the Z and X axis to start the construction of the slot. Trim the lines in the sketch and insert the dimensions to fully constrain the sketch. Ensure that you dimension from both sides of the Z axis as shown in the figure. (Figure Step 13A and 13B)
MUST KNOW: An assembly file does do not contain any of the part files that are placed in the assembled model. It simply contains a reference to the part files. A reference is a link back to the part files. The part files that have been placed in an assembly file must be available to Inventor to display them when the assembly file is opened.
The project file keeps track of those links and will automatically keep track of the location of all the files. If an assembly file (.iam) is sent to a client or an associate, the part files (.ipt) that were placed in the assembly file must also be included otherwise they will not display when the file is opened.
Step 14
Extrude the sketch. Set it to extrude in both directions and to cut. Set the distance to All. Complete the part by adding the hole, the threads, the fillets, the colour, and the material as specified in Figure 14A, 14B, and 14C.
Step 15
Create Part C. (Figure Step 15A, 15B, 15C, and 15D):
Part: Wedge Ring
Part Name: Inventor Workalong 22-1C
Template: English-Modules Part (in).ipt
Color: Titanium – Polished
Material: Titanium
Step 16
Construct Part D. (Figure Step 16A and 16B)
Part: Wedge
Part Name: Inventor Workalong 22-1D
Template: English-Modules Part (in).ipt
Color: Chrome – Polished
Material: Steel
Step 17
Change the face colour of the top face of the part to: Metal Steel (Knurled) as shown in Figure 16A.
Step 18
Construct Part F as follows: (Figure Step 18A and 18B)
Part: Handle
Part Name: Inventor Workalong 22-1E
Template: English-Modules Part (in).ipt
Color: Metal-AL-6061 – Machined
Material: Steel
Step 19
Construct Part E as follows: (Figure Step 19A, 19B, and 19C)
Part: Screw
Part Name: Inventor Workalong 22-1F
Template: English-Modules Part (in).ipt
Color: Metal-AL-6061 – Machined
Material: Steel
Step 20
Change the face colour of the cylindrical top of the part to: Metal Steel (Knurled) as shown in the solid model figure.
Inventor Command: PLACE COMPONENT
The PLACE COMPONENT command is used to insert a part or a component into an assembly file.
Shortcut: P
Inventor Command: PLACE CONSTRAINT
The PLACE CONSTRAINT command is used to apply constraints of one part to another in the assembled model.
Shortcut: C
Grounded Parts
By default, the first part that is placed into an assembly file will be grounded. A grounded part is a part that has all of it degrees of freedom removed and is fully constrained in that file. It is important to ground at least one part of every assembly. If no parts are grounded, the assembly can be moved around in model space. Once one part is grounded, the other parts can be constrained to it making their movement relative to the grounded part. If required, more then one part can be grounded.
In the Browser bar, a grounded part will display a Push Pin icon as shown in Figure 22-3 and 22-4. To enable or disable a part being grounded, right-click the part in the Browser bar. In the Right-click menu, select Grounded. In Figure 22-5, the selected part is currently grounded, enabled and visible.
Part Visibility
The visibility of parts in an assembly can be enabled or disabled. When the part’s visibility is disabled in the assembly, the part’s icon in the Browser bar will display greyed out.
Enabled Parts
Parts can be enabled or disabled in the assembly file. If a part is enabled, it displays and can be selected in the assembly. If it is disabled, only an outline displays and It cannot be selected. Sometimes it is easier to disable some parts to make it easier to place additional parts.
Assembly Constrains
There are many different constraints used when creating an assembly. In this module, only the mate constraint will be taught. A mate constraint constrains two assembled parts to one another by mating their centerlines and/or by mating a face on one part to a face on the other part. Mating is the most common way to assemble two parts together. It often takes more then one constraint to assemble two parts together. Both parts must have a symmetrical feature to mate them using the centerline method.
MUST KNOW: By default, the first part that is placed into an assembly file will be grounded. A grounded part is a part that has all of it degrees of freedom removed and is fully constrained in that file. It is important to ground at least one part in every assembly since if no parts are grounded, the assembly can be moved around model space. Once one part is grounded, the other parts can be constrained to it making their movement relative to the grounded part. USER TIP: The Browser bar contains a great deal of information about the active assembly file. The grounded part has a Push Pin icon. If a part is disabled, it will display a green part icon and if its visibility is disabled, the part icon will be grey as you can see in the figure.
WORKALONG: Creating an Assembly
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Using the NEW command, enable the English tab and select the temple file: Modules Assembly (in).iam. Save and name the assembly: Inventor workalong 22-1. (Figure Step 2)
Step 3
Enter the PLACE COMPONENT command. In the Place Component dialogue box insert part files: Inventor Workalong 22-1A.ipt and Inventor Workalong 22-1B.ipt into the assembly file. (Figure Step 3A and 3B)
USER TIP: By default, the PLACE COMPONENT command places multiple parts. To insert the part more than once into the assembly file, click once for each part. Ensure that you move the cursor so you are not inserting one part on top of another one. When you have inserted the required part(s), press Esc to exit the command.
Step 4
Disable the grounding of part 22-1A and enable the grounding of part 22-1B. (Figure Step 4A, 4B, and 4C)
Step 5
Enter the PLACE CONSTRAINT command. In the Place Constraint dialogue box set Type to Mate, Selections to 1, Offset to 0.000 and Solution to Mate. (Figure Step 5)
Step 6
Move the cursor onto the part 22-1A and move it until the Centerline constraint symbol appears. When it displays as shown in the figure, select it. Move the cursor onto the part 22-1B and do the same. Part 22-1A will move onto Part 22-1B. Click Apply. (Figure Step 6A, 6B, and 6C)
Step 7
Move the cursor onto the top of the base on part 22-1B as shown in the figure. The mate arrow will display pointing up. Press F4 and rotate the model. Select the mate constraint for the bottom of the part 22-1A. (Figure Step 7A, 7B, and 7C)
Step 8
Press F6 to change the Home view. (Figure Step 8)
Step 9
Enter the PLACE COMPONENT (P) command and insert part 22-1C, 22-1D, 22-1E, and 22-1F. Ensure that you place each part only once. (Figure Step 9)
Step 10
Using what you just learned, assemble and constrain part 22-1C. (Figure Step 10)
Step 11
Using the PLACE CONSTRAINT command, constrain the arc in part 22-1D to the arc in part 22-1C. (Figure Step 11)
Step 12
In the Offset box, set the offset to 0.015. Enable the Pick Part First box. See the Author’s Comments below. (Figure Step 12)
Step 13
To constrain the wedge in the slot, select one side of the slot and one side of the wedge as the mate surfaces. (Figure Step 13A, 13B, and 13C)
Step 14
Using what you just learned, constrain the last two parts to complete the assembly. (Figure Step 14)
Step 15
Save and close the file.
Key Principles
Key Principles in Module 22
1. An assembly file contains the information required to assemble two or more part files to create the assembled model. An assembly file has the file extension .iam.
2. An assembly file does do not contain any of the part files that are placed in the assembled model. It simply contains a reference to the part files. If an assembly file (.iam) is sent to a client or an associate, the part files (.ipt) that were placed in the assembly file must also be included otherwise they will not display when the assembly file is opened.
3. By default, the first part that is placed into an assembly file will be grounded. A grounded part is a part that has all of it degrees of freedom removed and is fully constrained in that file.
4. There are many different constraints used when creating an assembly. A mate constraint constrains two assembled parts to one another by mating their centerlines and/or by mating a plane on one part to a plane on the other part.
Lab Exercise 22-1
Time allowed: 180 minutes.
Part Name Project Units Template Color Material
Inventor Lab 22-1 Inventor Course Millimeters See Below See Below See Below
Step 1
Create the following parts.
Step 2
Each part must have its own file. In each part, ensure that you do the following:
A Select your own location of X0Y0Z0.
B Draw the necessary sketches and extrude or revolve them to produce the solid model shown. Apply all of the necessary geometrical and dimensional constraints to fully constrain all sketches. (Figure Step 2A and 2B)
C Apply the colour and material shown.
Part: Tire
Part Name: Inventor Lab 22-1A
Template: Metric-Modules Part (mm).ipt
Color: Rubber – Green – Version 1.1
Material: Rubber
Part: Frame
Part Name: Inventor Lab 22-1B
Template: Metric-Modules Part (mm).ipt
Color: Aluminum – Polished
Material: Steel (Figure Step 2C and 2D)
Part: Bushing
Part Name: Inventor Lab 22-1C
Template: Metric-Modules Part (mm).ipt
Color: Brass – Satin
Material: Brass (Figure Step 2E and 2F)
Part: Pin
Part Name: Inventor Lab 22-1D
Template: Metric-Modules Part (mm).ipt
Color: Semi – Polished
Material: Steel (Figure Step 2G, 2H and 2J)
Part: 10 mm Nut
Part Name: Inventor Lab 22-1E
Template: Metric-Modules Part (mm).ipt
Color: Semi – Polished
Material: Steel (Figure Step 2K and 2L)
Part: Bolt
Part Name: Inventor Lab 22-1F
Template: Metric-Modules Part (mm).ipt
Color: Semi – Polished
Material: Steel (Figure Step 2M and 2N)
Part: 12 mm Nut
Part Name: Inventor Lab 22-1G
Template: Metric-Modules Part (mm).ipt
Color: Semi-Polished
Material: Steel (Figure Step 2P and 2Q)
Part: Washer
Part Name: Inventor Lab 22-1H
Template: Metric-Modules Part (mm).ipt
Color: Semi-Polished
Material: Steel (Figure Step 2R and 2S)
Step 3
Open a new assembly file.
Assembly: Caster
File Name: Inventor Lab 22-1.iam
Template: Metric – Modules Assembly (mm).iam
Step 4
Set the Tire as the grounded part.
Step 5
Start with assembling the Bushing into the Tire first. (Figure Step 5)
Step 6
Assemble the remaining parts to complete the assemble file. (Figure Step 6A and 6B) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/05%3A_Part_5/5.01%3A_Module_22_Assemblies.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe a presentation file, an exploded assembly, and an animation.
2. Describe and apply the CREATE VIEW, PRECISE VIEW ROTATION, TWEAK COMPONENT, and ANIMATE commands to create, tweak, and play the animation of an exploded assembly.
Presentation Files
After the model is assembled in the assembly file, a presentation file can be created using it. A presentation file is a file in which a view of an assembly is exploded and can be animated. It can also be rotated so that is can be viewed from different angles. A presentation file is created using the NEW command and selecting a presentation template. A presentation file has the extension .ipn. IPN is an acronym for Inventor PreseNtation.
Exploded Views
An exploded view shows the assembly as if it were dismantled and the components of the assembly shown in the order and orientation that they fit together to create the assembly. Assemblies can be exploded automatically by Inventor, tweaked manually, or a combination of the two methods, complete with trails. A tweak is the distance that the part is moved from the grounded part while the trails are the lines in an exploded view that show the relationship of the component to the assembly. Combined, they indicate the direction and distance that a component was moved to create the view. Exploded assembly drawings are used in design presentations, catalogues, and assembly instruction. Figure 23-1 shows an exploded and rotated view of an assembly.
Animations
An animation is a series of images of an exploded assembly showing each components tweak at a set interval speed making a small motion picture of an assembly or a disassembly.
Tweaking
Tweaking is the process of moving the components from the grounded component. The tweak is the distance measured from the grounded unit. In the automated explosion method, the tweak distance is same for each part. If the tweak distance is set to 35, that means the first part is 35 mm from its location and the second part is 70 mm etc. This can be seen if the children in the Browser bar are expanded as shown in Figure 23-2. To tweak components manually, use the TWEAK COMPONENT command.
Animating the Exploded Assembly
After the exploded assembly is tweaked, it can animated to show the assembly and the disassembly of the model. An animation is simply a series of frames or pictures of the assembly displayed one frame at a time. The amount of time between frames is called the interval. The larger the interval, the slower the animation and the shorter the interval, the faster the animation. The number of repetitions can also be set.
Inventor Command: CREATE VIEW or INSERT MODEL
The CREATE VIEW or INSERT MODEL commands are used to insert the model of the assembly file.
Shortcut: none
Inventor Command: TWEAK COMPONENTS
The TWEAK COMPONENTS command is used to move a component farther or closer from the grounded component to create or edit an exploded view of the assembly. It can also be used to rotate the components.
Shortcut: T
Inventor Command: ANIMATE
The ANIMATE command is used to set the parameters and play an animation of an assembly or disassembly of a assembled model.
Shortcut: none
MUST KNOW: A presentation file is a file in which a view of an assembly is created, rotated, exploded, and animated. To create a presentation file, use the NEW command and select a presentation template. A presentation file has the extension .ipn. IPN is an acronym for Inventor Presentation.
WORK ALONG: Creating an Assembly and Presentation File
Step 1
Check the default project and if necessary, set it to Inventor Course.
Step 2
Use the following instructions to complete all parts in this workalong. Create the following parts and ensure that you do the following:
A Each part must be saved in its own .ipt file.
B Project the Center Point onto the Base sketch plane and note the location of X0Y0Z0.
C Draw the necessary sketches and extrude or revolve them to produce the solid model. Apply all of the necessary geometrical and dimensional constraints to fully constrain it.
D Apply the colour and material shown.
Step 3
Create the part file as follows:
Part: Base
Part Name: Inventor Workalong 23-1A Template: Metric-Modules Part (mm).ipt Color: Aluminum Cast Material: Aluminum 6061 (Figure Step 3A and 3B)
Template: Metric-Modules Part (mm).ipt
Color: Aluminum
Cast Material: Aluminum 6061 (Figure Step 3A and 3B)
Step 4
Change the colour of the machined faces to: Mirror.
Part: Slotted Wheel
Part Name: Inventor Workalong 23-1B
Template: Metric-Modules Part (mm).ipt
Color: Mirror
Material: Chrome – Polished Blue (Figure Step 4A, 4B, and 4C)
Part: Connecting Shaft
Part Name: Inventor Workalong 23-1C
Template: Metric-Modules Part (mm).ipt
Color: Copper – Polished
Material: Copper (Figure Step 4D and 4E)
Part: Spacer
Part Name: Inventor Workalong 23-1D
Template: Metric-Modules Part (mm).ipt
Color: Blue – Wall Paint – Glossy
Material: ABS Plastic (Figure Step 4F and 4G)
Part: Washer
Part Name: Inventor Workalong 23-1E
Template: Metric-Modules Part (mm).ipt
Color: Steel – Polished
Material: Steel (Figure Step 4H and 4J)
Part: Nut
Part Name: Inventor Workalong 23-1F
Template: Metric-Modules Part (mm).ipt
Color: Steel – Polished
Material: Steel (Figure Step 4K and 4L)
Step 5
Assemble all of the parts that you just created as shown in the figures.
Assembly: Slotted Connector
Assembly Name: Inventor Workalong 23-1.iam
Template: Metric-Modules Assembly (mm).iam (Figure Step 5A and 5B)
Step 6
Enter the NEW command and enable the Metric tab. Select the template file: Modules Presentation (mm).ipn (Figure Step 6)
Step 7
Enter the CREATE VIEW command. It will open the Select Assembly dialogue box. (Figure Step 7)
Step 8
Click the Search Folder icon at the end of the file name. It will open the Open dialogue box. In the Lab Exercises folder, select the file: Inventor Workalong 23-1.iam and click Open. (Figure Step 8)
Step 9
In the Select Assembly dialogue box enable Automatic and Create Trails in the Explosion Method area. Enter the Distance of 35 mm. Click OK. The exploded assembly should appear as shown in the figure. (Figure Step 9A and 9B)
Step 10
Enter the PRECISE VIEW ROTATION command. In the Incremental View Rotate dialogue box, set the Increment to 10. (Figure Step 10)
Step 11
Click the Right Rotate icon twice. This will rotate the model 20 degrees to the right. Click the Up Rotate icon once. This will rotate the model 10 degrees upwards. (Figure Step 11)
Step 12
Enter the TWEAK COMPONENTS command. It will open the Tweak Component dialogue box. Set it as shown in the figure. (Figure Step 12)
Step 13
Ensuring that Direction is enabled, zoom in and move the cursor on the top of the nut. When the direction icon is displayed as shown in the figure, click the left mouse button. (Figure Step 13A and 13B)
Step 14
Look at the Browser bar for the tweak you just created. It will show two tweaks for part:
Inventor Workalong 23-1F:1, which is the nut. The 175.000 mm tweak was created in the automatic explosion in Step 9 and the 185.000 mm from the manual tweak you just completed. (Figure Step 14)
Step 15
Click the Clear button to clear the current settings. Using the Browser bar in Figure Step 15A, manually tweak the assembly to match the figure shown in Figure Step 15B. (Figure Step 15A and 15B)
Step 16
Enter the ANIMATE command. It will open the Animation dialogue box. Set the Interval to 25 and the Repetitions to 1. (Figure Step 16)
Step 17
Study Figure Step 17A, 17B, 17C, and 17D. Play the animation of the assembly that you created in this workalong. Try the different options allowed in the Motion box. (Figure Step 17A, 17B, 17C, and 17D)
Step 18
Set the Interval to 15 and the Repetitions to 3. Play the animation using these parameters both forward and in reverse. (Figure Step 18)
Step 19
Save and close the file.
USER TIP: The tweaked distance can be edited in the Browser bar. Locate the tweak you want to change and select it. Once selected, it will highlight and at the bottom of the browser bar you can change the distance as shown in figure below left. The revised tweak will display as shown in the figure below right.
Key Principles
Key Principles in Module 23
1. A presentation file is a file in which a view of an assembly is exploded and can be animated. It can be rotated so that is can be viewed from different angles.
2. An exploded view shows the assembly as if it were dismantled and the components of the assembly shown in the order and orientation they fit together to create the assembly.
3. A tweak is the distance that the part is moved from the grounded part while the trails are the lines in an exploded view that show the relationship of the component to the assembly.
4. After the exploded assembly is tweaked, it can animated to show the assembly and the disassembly of the model. An animation is simply a series of frames or pictures of the assembly displayed one frame at a time. The amount of time between frames is called the interval. | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/05%3A_Part_5/5.02%3A_Module_23_Presentation_Files.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe 2D drawing files, drawing sheets, and drawing sizes.
2. Describe and apply the commands BASE VIEW, PROJECTED VIEW, SECTION VIEW, and NEW SHEET to create multiview and isometric views of a solid model on a drawing sheet.
Drawing Files
A drawing file contains one or more drawing sheets on which 2 dimensional and/or 3 dimensional scaled views of the solid models contained in part, assembly, or presentation files. The views can be created complete with hidden lines or shading. Annotation can be automatically or manually added to the views as required. A typical drawing sheet with an orthographic, section, and isometric view of a model is shown in Figure 24-1. Dimensioning, inserting text, and filling in the titleblock are taught in Module 25. When the drawing is complete, it can be printed or plotted on paper. A drawing file has the file extension .idw. IDW is an acronym for Inventor Drawing.
Model Views
Amodel view is a scaled view orientated at an angle and direction that the solid model or assembly is being viewed and displayed on the drawing sheet. There is no limit to the number of views or the number of solid models from part, assembly, or presentation files that can be placed on a drawing sheet. Views can also be automatically annotated or labeled. There are eight predefined views that you can select from when creating the view. The predefined views are the; base, projection, auxiliary, section, detail, broken, breakout, and overlay.
The Base
A Base view is the first view created on the drawing sheet. It controls the scale, orientation, and location of the views projected from it. The orthographic and/or isometric views in the drawing are created from the Base view. For example, if a multiview drawing was being created from a solid model, the Front view is created first as a Base view. The Front view would control the scale and location of the projected Top and Right Side views. See Figure 24-2. To change the scale of all views, only the scale of the Front (Base) view would have to be changed and the Top and Right Side views would automatically change scale to match. If the Front view was moved, the Top and Right Side views would move accordingly to keep their multiview position.
Projected Views
A projected view is a view projected from a Base view. The scale of a projected view cannot be set since the Base view that you projected it from controls its scale. The Base view also controls the orientation and location of the projected views.
Drawing Sheets
A drawing sheet represents a blank piece of paper complete with titleblock and border. The size of drawing sheet can be set by the user. The sheet size can be a custom size set by you or one of the ANSI or ISO drawing sheet standards listed in the table shown in Figure 24-3.
There is no maximum number of drawing sheets that can be created for each drawing file but there must be at least one sheet. Sheets can be created or deleted but Inventor will NOT allow all of them to be deleted since one sheet must exist at all times.
The drawing sheet can be assigned a drawing border and a titleblock which can be created or edited by you. Custom drawing template files containing borders and titleblocks are supplied with the Inventor book.
MUST KNOW: There is no maximum number of drawing sheets that can be created for each drawing file but there must be at least one sheet. One sheet must exist in each drawing file at all times.
View Style
Aview style can be displayed in one of three different styles. The three styles are hidden line, hidden line removed, and shaded as shown in Figure 24-4. The style of a view can be changed as required after the view has been placed.
View Scale
The scale of the view is a factor of the number that it is set to. For example, if the scale is set to 1 then the factor of 1 X 1 = 1, full scale or 1:1. If the scale is set to 2 then 2 X 1 = 2 or a scale of 2:1 which is twice the size of the original model. On the other hand, if the scale factor is set to 0.5 then 0.5 X 1 = 0.5 or the scale of 1:2 which would display the view one-half the size of the original model.
MUST KNOW: A drawing file contains one or more 2 dimensional drawing sheets on which a 2D and/or 3D scaled views of solid models contained in part, assembly, and presentation files. A drawing file has the file extension .idw. IDW is an acronym for Inventor Drawing.
Inventor Command: BASE VIEW
The BASE VIEW command is used to create a Base view of the solid model contained in a part, assembly, or presentation file on the drawing sheet. The scale, style, labeling, and orientation of the view can be set when the view is created.
Shortcut: none
Inventor Command: PROJECTED VIEW
The PROJECTED VIEW command is used to create a projected view from a Base view. The style, labeling, and direction from the Base view can be set by you when the view is created.
Shortcut: none
Inventor Command: SECTION VIEW
The SECTION VIEW command is used to create a Section view from an existing view. The location, style, labeling, and direction from the selected view can be set by you when the view is created.
Shortcut: none
USER TIP: ANSI is an acronym for American National Standard Institute. ANSI has set drawing standards that are widely adapted and followed by most companies working in English or Imperial measurements. To read more about ANSI see: http://www.ansi.org/
ISO is an acronym for International Organization for Standardization. ISO has set the drawing standards that are widely adapted and followed by most companies working in Metric measurements. To read more about ISO see: http://www.iso.org/iso/en/ISOOnline.frontpage
WORK ALONG: Creating 2D Drawings
Step 1
Check the default project and if necessary, set it to: Inventor Course.
Step 2
Enter the NEW command to start a new drawing file. Enable the English tab and select the template: Modules Drawing ANSI (in).idw. (Figure Step 2)
Step 3
When the drawing file is opened, it will display an A size drawing complete with border and titleblock. Save the file with the name: Inventor Workalong 24-1. (Figure Step 3)
Step 4
Enter the BASE VIEW command to create the Base view. It will open the Drawing View dialogue box. Set the Orientation (view) to Front and the Style to Hidden Line. Ensure that the dialogue box matches the figure. (Figure Step 4)
Step 5
Click OK. In the Open dialogue box, select the part: Inventor Workalong 22-1D.ipt. (Figure Step 5)
Step 6
Select the location for the Front view. Don’t be too concerned where you locate it since it can be moved later. Try to locate it close to where it is shown in the figure. (Figure Step 6A and 6B)
Step 7
Enter the PROJECT VIEW command and select the Base view as the view to project from. (Figure Step 7)
Step 8
Move the cursor up to locate the Top view. Click the mouse at the desired location. Right click the mouse. In the Right-click menu, select Create. (Figure Step 8A and 8B)
Step 9
Using what you just learned, use the PROJECT VIEW command to create the Right Side view. (Figure Step 9)
Step 10
Your drawing should now contain the Top, Front and Right Side views of the part. (Figure Step 10)
Step 11
Enter the PROJECT VIEW command. Select the Base view (Front view) and project an Isometric view from it. (Figure Step 11)
Step 12
Right click the Isometric view. In the Right-click menu, click Edit View. (Figure Step 12)
Step 13
In the Edit View dialogue box enable the display View/Scale label (turn the light bulb on). Set the Scale to 0.75:1, View Identifier to ISOMETRIC and the Style to Shaded. (Figure Step 13A and 13B)
Step 14
Right click the file name in the Browser bar. In the Right-click menu, click New Sheet. An A size drawing sheet will display in the Graphic window. The new sheet will be labeled Sheet:2 and will display in the Browser bar. (Figure Step 14)
Step 15
Right-click Sheet:2. In the Right-click menu, click Edit Sheet. In the Edit Sheet dialogue box, pull down the Size list and select B to change Sheet 2 to a B size. Ensure that Landscape is enable. (Figure 15A, 15B, and 15C)
Step 16
Using what you just learned, create a Base view of Top view of part: Inventor Workalong 22-1C.ipt that you created in Module 22. (Figure Step 16)
Step 17
Enter the SECTION VIEW command. Move the cursor to the centre of the circle on the Top view until it displays the green snap circle. You may have to move the cursor touching the circle circumference and then move back to the centre. Do NOT select the green snap circle, wait until it displays. Move the cursor to the right and you will see a dashed line indicating an implied line which is orthographic or horizontal, in this case. move outside the view. The yellow grid snap circle will display. Select a location when the grid snap is displayed. (Figure Step 17A and 17B)
Step 18
Move the cursor across to the other side of the view and when the geometry constraint (horizontal) displays, select a location about the same distance from the view as you did for the other side of the view. Right-click the mouse. In the Right-click menu, select Continue. (Figure Step 18A and 18B)
Step 19
Move the cursor down and the section view will display. The Section View dialogue box will open. Set the dialogue box as shown in the figure. (Figure Step 19A and 19B)
Step 20
Using the BASE VIEW command, create an Isometric view and set the scale to 1.25:1. (Figure Step 20)
Step 21
Save and close the drawing file.
USER TIP: The default labels and colors can be configured for each drawing file. Originally, these setting came from the template file that you used to start the drawing file. Any changes that you make will only affect the current drawing file. Enter the DOCUMENT SETTINGS command. See figure right. To change the default labels of the sheets, simply edit the value as shown in the figure below. To change the background colour of the Sheet, the Sheet Outline, Highlight or Selection, select the one you want from the Color dialogue box. In this example, the colour of the sheet was change to white. USER TIP: To move a view on the drawing sheet, move the cursor onto the view’s border. When you are on the border, it will highlight as shown in Step 1. If the view is a base view or a projected view that has a view dependent on it, the Graphic cursor will display as shown on the left. If the view is a Base view or a projected view that does NOT have view dependent on it, the cursor will display as shown on the right. To move a view, simply press and hold down the left mouse button and drag it to desired location as shown in Step 2.
Key Principles
Key Principles in Module 24
1. A drawing file contains one or more 2 dimensional drawing sheets on which a 2D and/or 3D scaled views of solid models contained in part, assembly, and presentation files. A drawing file has the file extension .idw. IDW is an acronym for Inventor Drawing.
2. A Base view is the first view created by the user. It controls the scale, orientation, and location of the orthographic views projected from it.
3. A projected view is a view projected from a Base view. The scale of a projected view cannot be set since the Base view that you projected it from controls its scale. The Base view also controls the orientation and location of the projected views.
4. A drawing sheet represents a blank piece of paper complete with titleblock and border. The size of drawing sheet can be set by the user. The sheet size can be a custom size set by the user or one of the ANSI or ISO drawing sheet standards.
5. There is no maximum number of drawing sheets that can be created for each drawing file but there must be at least one sheet. One sheet must exist in each drawing file at all times.
6. A view style can be displayed in one of three different styles. The three styles are hidden line, hidden line removed, and shaded. The style of a view can be changed as required after the view has been placed.
7. The scale of the view is a factor of the number that it is set to.
Lab Exercise 24-1
Time allowed: 2 hours.
Part Name Project Units Template Color Material
See Below Inventor Course Inches See Below N/A N/A
Step 1
Create the following drawings and ensure the following:
A There is a separate file for each drawing sheet.
B Create the same views as shown.
C If the scale is not indicated, set it to full scale or 1:1.
D Each drawing file has only one drawing sheet.
E Save the drawing files with the Drawing Name shown for each part.
Part: Base
Drawing Size: B
Drawing Name: Inventor Lab 24-1A.idw Part Name: Inventor Workalong 22-1A.ipt
Template: English-Modules Drawing ANSI (in).idw (Figure Step 1A)
Part: Post
Drawing Size: C
Drawing Name: Inventor Lab 24-1B.idw
Part Name: Inventor Workalong 22-1B.ipt
Template: English-Modules Drawing ANSI (in).idw (Figure Step 1B)
Part: Screw
Drawing Size: A
Drawing Name: Inventor Lab 24-1C.idw
Part Name: Inventor Workalong 22-1E.ipt
Template: English-Modules D
rawing ANSI (in).idw (Figure Step 1C)
Assembly: Tool Holder
Drawing Size: A
Drawing Name: Inventor Lab 24-1.idw
Part Name: Inventor Workalong 22-1.iam
Template: English-Modules Drawing ANSI (in).idw (Figure Step 1D) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/05%3A_Part_5/5.03%3A_Module_24_2D_Drawings__Part_1.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Describe basic dimensioning, centerlines, and standard styles.
2. Describe and apply the STYLES EDITOR command to copy and edit standard styles to create your own dimension and text styles.
3. Describe and apply the RETRIEVE DIMENSION, CENTERLINES, and GENERAL DIMENSION commands to place model and drawing dimensions and centerlines on drawing views.
4. Describe how styles are exported out of and imported into drawing files.
Drafting Lesson: Basic Dimensioning Terms
Figure 25-1 shows the basic dimensioning terms that you will need to know when setting the standards for dimensioning style.
Dimensioning
Dimensioning is the process of adding size descriptions to the orthographic views of the model that are placed on a drawing. Once a orthographic views of the model are dimensioned, the drawing sheet can then be plotted and used for construction or reference. Up to this point in the modules only shape and size descriptions have been added to the solid models that are been constructed by adding geometrical and dimensional constraints. Since Inventor knows the exact size of the solid models, the drafter/designer only has to control which dimensions are shown and where to position them.
Dimensioning is a complex subject, not difficult, but there is a lot to learn. Therefore, in the Inventor Modules, learning to control the appearance and location of the basic dimension types is taught. As the Inventor user gets more experience dimensioning he/she can experiment with some of the advanced dimensioning features.
Dimensioning Styles
A dimensioning style is a named set of variables or settings that controls the way the dimensions will appear on the drawing. There are many different settings in a dimensioning style so it will take the user some time to get used to setting them. Be patient and practice editing styles and inserting dimensions as often as possible.
Inventor comes with several preset dimensioning styles which are part of the template that was used when the drawing file was created. They can be edited but cannot be renamed. It is better to create a new style by copying an renaming one of the Inventor standards and make the necessary changes to it. After the editing is complete, name the style with an appropriate name and save it so that it can be identified and used again at a later date. Dimensioning styles can also be exported and imported from one drawing to another.
Text Styles
A text style is a named set of variables or settings that controls the way text will appear on a drawing. Inventor comes with several preset text styles which were part of the template that was used when the drawing file was created. Although they can be edited, they cannot be renamed. If changes are required, it is better to create a new text style by copying one of the Inventor standards and make the necessary changes to it. After the editing is complete name the style with an appropriate name and save it so that it can identified and used at a later date. Text styles can also be exported and imported from one drawing to another.
Centerlines
A centerline is used in technical drawings to indicate the location of the axis of symmetry. Placing centerlines on all objects that have a symmetrical shape will help others who are reading the drawing. The proper use of centerlines also cut down on the number of dimensions that are required on a drawing to fully describe the object.
Placing Dimensions
The two types dimensions that can placed on a drawing are model dimensions and drawing dimensions.
Model Dimensions
Model dimensions are the driven and driving dimensions that were placed in the 2D sketch when the model was being constructed. The RETRIEVE DIMENSION command is used to retrieve the dimensions from the model and display them on the drawing. If the driven dimensions in the original sketches are changed in the future, the model dimensions in the drawing will automatically change since they are showing the actual size of the model.
Drawing Dimensions
Drawing dimensions are dimensions that are placed in the drawing using the GENERAL DIMENSION command. Dimensions are placed exactly where they are located in the 2D sketch when the model was created. Inventor will obtain the actual sizes and if the model is changed in the future, the drawing dimensions will automatically change to reflect the new size of the model.
Inventor Command: STYLES EDITOR
The STYLES EDITOR command is used to create and/or edit the styles and standards used by a drawing file.
Shortcut: none
Inventor Command: RETRIEVE DIMENSIONS
The RETRIEVE DIMENSIONS command is used to retrieve model dimensions from the sketches used to create the solid model. Only dimensions that are parallel to the plane of the view will display. The user can select the dimensions that they want to display on the drawing.
Shortcut: none
Inventor Command: TEXT
The TEXT command is used to place text on the a drawing sheet. It uses the default text style when the text is inserted.
Shortcut: none
Drafting Lesson: Center Lines
In multiview drawings, the center line is used to indicate the location of the axis of symmetry. Placing centre lines on all objects that have a symmetrical shape will help the reader and save the you from inserting a lot of dimensions as you will see in future modules. Below are some examples of typical applications of the use of centre lines in a multiview drawing.
A ‘ C ‘ with an ‘ L ‘ through it is the symbol for a centre line. Center lines are drawn as repeating long and short lines. See Figure 37-2.
Figure 37-3 shows a centre line indicating the centre of the circle with two short lines called a center mark intersecting at the centre. Note in the right side view, the centre line follows the length of the cylinder.
When the symmetry ends, so does the centre line. Note how the centre line ends on the left side of the arc. See Figure 37-4
Figure 37-5 shows the centre lines along with the hidden lines that indicate a hole going through the object. The centre line on the top and bottom circles stops at the circle.
In Figure 37-6, note how centre lines are drawn for an array of circles.
There are four icons used to place centerlines on the drawing. In this module, you will be using three of them. The Center Mark, Centerline, and Centered Pattern icons are shown in Diagrams F1, G1 and H1. Diagrams F2, G2 and H2 show what centerline the applicable icon will place.
WORK ALONG: Creating Dimensioning and Text Styles
Step 1
Check the default project and if necessary, set it to: Inventor Course.
Step 2
Open the drawing file: Inventor Lab 24-1A.idw. (Figure Step 2)
Step 3
Enter the STYLES EDITOR command to open the Styles and Standard Editor dialogue box. Expand the children under the heading Dimension from the list of styles and standards on the left side of the dialogue box. The seven dimensioning styles listed are the styles that are already contained in your drawing. They were in the template file that you used when you created the drawing. (Figure Step 3)
Step 4
Right-click the dimensioning style: Default (ANSI). In the New Style Name dialogue box, enter the name: Modules in ANSI. Ensure that you enable the Add to Standard and then click OK. (Figure Step 4A and 4B)
Step 5
Click the dimensioning style: Modules in (ANSI) in the style list on the left side of the dialogue box to make it the current style. Note that on the right side of the dialogue box your newly created style is listed at the top above the tabs. This indicates it can be edited in the dialogue box. Enable the Units tab. (Figure Step 5A and 5B).
Step 6
Change the Linear and Angular box to match the settings shown in the figure. (Figure Step 6)
Step 7
Enable the Display tab and if necessary, make any changes until it matches the figure. (Figure Step 7)
Step 8
Enable the Options tab and if necessary, make any changes until it matches the figure. (Figure Step 8)
Step 9
Enable the Notes and Leaders tab and if necessary, make any changes until it matches the figure. (Figure Step 9)
Step 10
Click the Save button to save the changes you made to the dimensioning style: Modules in ANSI. Click Done to close the dialogue box. (Figure Step 10)
MUST KNOW: The default dimension styles cannot be renamed nor should they be altered. It is always best to create your own style using a default style to copy from. After you edit it to make the changes to suit the required style, name and save the style. Pick an appropriate name so that you can easily find and use it in the future.
Step 11
Expand the children under the heading Text from the list of styles and standards on the left side of the dialogue box. The style names listed are the text styles that are already contained in your drawing. (Figure Step 11)
Step 12
Right click the style: Note Text (ANSI). In the right-click menu, select New Style. (Figure Step 12)
Step 13
This will open the New Style Name dialogue box as shown in the figure. Note that since the text style: Note Text (ANSI) was the current style, you will be starting with a copy of its settings. Enter the name: Modules Note Text (ANSI) and click OK. Ensure that Add to standard is enabled. (Figure Step 13)
Step 14
Make any changes necessary to match the figure. (Figure Step 14)
Step 15
Click the Save button to save the changes you made to the text style.
Step 16
Use what you learned earlier in the workalong, make the dimensioning style: Modules in ANSI the active style. (Figure Step 16)
Step 17
Enable the Text tab. Pull down the Primary Text Style pull-down box and select the text style: Modules Note Text (ANS)I. This will make it the default text style for the dimensioning style: Modules in ANSI. (Figure Step 17)
Step 18
The Text tab in the active dimension style: Modules in ANSI should appear as shown in the figure.
Step 19
Click the Done button and if you are asked to Save Edits, click Yes. (Figure Step 19)
Step 20
Save and close the drawing file.
WORK ALONG: Adding Annotation to the Drawing
Step 1
Check the default project and if necessary, set it to: Inventor Course.
Step 2
Open the drawing file: Inventor Lab 24-1A.idw.
Step 3
Click the Centerline icon to place the vertical centerline on the Top view. For the first point, snap to the midpoint of the line on the top of the view. For the second point, snap to the midpoint of the bottom line of the Top view. Move the cursor a short distance below the Top view and click it to indicate the distance the centerline is to go past the view. (Figure Step 3A, 3B, 3C, and 3D)
Step 4
Using what you just learned, place the centerline on the Front view. (Figure Step 4)
Step 5
Open the Style and Standard Editor dialogue box. On the left side, expand the children in the Center Mark heading. Select Center Mark (ANSI) to make it the current style. (Figure Step 5)
Step 6
Right-click the standard style: Center Mark (ANSI) and click New Style. In the New Style Name dialogue box, enter the name: Modules Center Line Short (ANSI). (Figure Step 6)
Step 7
Select the new style that you just created to make it the current style. Make the changes shown in the figure. (Figure Step 7)
Step 8
Select the centerline in the Front view. It will highlight. (Figure Step 8)
Step 9
With the centerline selected, look on the Inventor Standard pull-down menu. Note how it shows Standard as the centerline type for selected object. Select the centerline style: Modules Center Line Short ANSI. (Figure Step 9A and 9B)
USER TIP: When creating and dimensioning the 2D sketches in future models, keep in mind how the RETRIEVE DIMENSION command works. It retrieves both driven and driving dimensions that are parallel to the plane of each vew. After placing the driven dimension to constrain the sketch, add the necessary driving
dimensions so that when you create the drawing and dimension the model, it will retrieve all of the dimensions required. That way, you will may not have to place any general dimensions.
Step 10
Enter the RETRIEVE DIMENSION command and in the Retrieve Dimensions dialogue box, ensure that Select View icon is enabled. Select the Top view. (Figure Step 10)
Step 11
In the Select Source box, enable Select Parts. Select all objects. The dimensions that you inserted in the sketches that are parallel to the plane will display. (Figure Step 11)
Step 12
Ensure that the Select Dimension icon is enabled select the dimension(s) that are selected in the figure. (Figure Step 12)
Step 13
Using what you just learned, select the dimensions for the Front view of the model. In this case, there was only one. (Figure Step 13)
USER TIP: To relocated a dimension on a drawing, move the cursor onto the dimension. When the cursor is on a dimension, it will highlight and the Move icon will display as shown in the figure to the right. The Move cursor is shown in the figure on the left. When the Move cursor displays, press and hold down on the left mouse button and drag the cursor to approximately the location you want to place the dimension. As you do that, Inventor will display a temporary centerline indicating the centre location between the extension lines as shown in the figure to the right. It will help you centre the dimension text. When you have the dimension positioned, release the mouse button.
Step 14
Move the dimensions to match the figure as close as possible. (Figure Step 14)
Step 15
Select all of the dimensions. Change the dimensioning style to: Modules in ANSI. To do this, while the dimensions are selected, pull down the standards list. From the dimension style list, find and select the style: Modules in ANSI in the pull-down list on the Inventor Standard menu. (Figure Step 15A , 15B, and 15C)
Step 16
Set the default dimensioning style before you insert the drawing dimensions. Pull-down the style standards list and select: Modules in (ANSI). It should now display as shown in the figure. When you insert your dimensions they will use the default dimensioning style. (Figure Step 16)
Step 17
Add the remainder of the dimensions to match the figure. This is done using the GENERAL DIMENSION (D) command, just like you did when creating your 2D sketches. (Figure Step 17A and17B)
Step 18
To add or edit dimension text, click the text and right-click the mouse. In the Right-click menu, select Text. This will open the Format Text dialogue box. (Figure Step 18)
Step 19
In the text box at the bottom of the dialogue box you will see the symbols << >>. This symbol indicates the actual model dimension. You cannot edit the dimension since Inventor gets the dimension from the model. To add text, click the cursor behind the symbol and enter a comma. Press the Enter key to go to a new line. Add the Figure Step 18 text 4 PLACES. (Figure Step 19)
MUST KNOW: The dimension text symbol “<< >>” signifies that the actual dimension number is a model or drawing dimension size. Inventor will obtain the actual dimension from the solid model and display it on the drawing. You cannot edit this number nor can you delete it. If the size of the model is modified, the dimension Inventor displays will change to reflect the true size of the model.
Step 20
Using what you just learned, add the text to the other radius dimension. (Figure Step 20)
Step 21
To fill-in the titleblock, simply change the drawing’s properties. To do that, right-click the drawing’s icon in the Browser bar. In the Right-click menu, click iProperties. The titleblock has been programmed to extract the properties of the current drawing file. It will open the Inventor Properties dialogue box. (Figure Step 21)
Step 22
Enable the Summary tab. Enter TOOL HOLDER – BASE in the Title box and your name in the Author box. (Figure Step 22)
Step 23
Enable the Project tab. Enter WORKALONG 25-1A in the Part Number box. Your titleblock should now appear as shown in figure. (Figure Step 23A and 23B)
Step 24
Enter the TEXT command and select the location to place the text on the drawing. The cursor will display as a plus sign. Move it to just above the titleblock as shown in the figure. (Figure Step 24)
Step 25
When you select the location for the text, the Format Text dialogue box will open. In the text box along the bottom of the dialogue box enter the text as shown in the figure. Ensure that the default text style is set to: Modules Note Text (ANSI) as shown in the dialogue box. (Figure Step 25)
Step 26
The completed drawing should appear similar to the figure. (Figure Step 26)
Step 27
Save and close the drawing.
Exporting and Importing Styles
When a style is created in a drawing file it is only useable in that drawing file. To save you re-creating the style in each new drawing file, the style can be saved as a file on the hard drive and then retrieve into another drawing. Saving the style file from a drawing is called exporting and retrieving it into a drawing is called importing.
WORK ALONG: Exporting and Importing Styles
Step 1
Using Windows Explorer, create the folder: Style Library in the existing folder: C:\CAD Courses\Inventor Course. (Figure Step 1)
Step 2
Start Inventor and check the default project. If necessary, set it to: Inventor Course.
Step 3
Open the drawing: Inventor Lab 24-1A.idw
Step 4
Open the Style and Standard Editor dialogue box. Find and select the style: Modules in (ANSI) under the Dimension heading. It is the dimensioning style that you created earlier in the module. Right-click the name. In the Right-click menu, select Export. (Figure Step 4)
Step 5
Select the Style Library folder you created in Step 1. In the File name: box, enter the file name: Modules in (ANSI). (Figure Step 5)
Step 6
Open a new drawing file. Enter the STYLE EDITOR command and in the dialogue box, click the Import box located along the bottom of the box. (Figure Step 6)
Step 7
This will open the Import style definition dialogue box. Click the folder Style Library and select the file: Modules in (ANSI) .styxml that you exported in Step 5. (Figure Step 7)
Step 8
Activate the file: Inventor Lab 24-1A.idw and export the other two styles that you created in this drawing. Figure Step 8 shows the three styles that should now be in the Style Library folder. You can check it using Windows Explorer. (Figure Step 8)
Step 9
Open a new drawing file. Enter the STYLE EDITOR command and in the dialogue box click the Import box located along the bottom of the box. This will open the Import style definition dialogue box. This will open the Import style definition dialogue box. With the Look in: box displaying the folder Style Library, select the file: Modules in (ANSI) .styxml that you exported in Step 5. (Figure Step 9)
Key Principles
Key Principles in Module 25
1. The default styles cannot be renamed nor should they be altered. It is always best to create your own named style using a default style to copy from.
2. A style is a named set of variables or settings that controls the way the annotation will appear on the drawing.
3. The RETRIEVE DIMENSION command is used to retrieve the driven and driving dimensions from the model and display them on the drawing. If the driven dimensions in the original sketches are changed, the model dimensions in the drawing will automatically change.
Lab Exercise 25-1
Part Name Project Units Template Color Material
See Below Inventor Course Inches See Below N/A N/A
Step 1
Create the drawing shown below. Ensure that you:
A Retrieve as many model dimensions as you can.
B Add the drawing dimensions to complete the drawing as shown below.
C Import the dimension style: Modules in (ANSI) and use it as the dimensioning style in your drawing. Match the drawing shown below.
D Save the drawing files with the drawing name shown below.
Part: Post
Drawing Size: D
Drawing Name: Inventor Lab 25-1.idw
Part Name: Inventor Workalong 22-1B.ipt
Template: English-Modules Drawing ANSI (in).idw (Figure Step 1A, 1B, and 1C) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/05%3A_Part_5/5.04%3A_Module_25_2D_Drawings__Part_2.txt |
Wally Baumback
Learning Outcomes
When you have completed this module, you will be able to:
1. Within a six hour time limit, complete a written exam and the lab exercise.
The Inventor book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.
If you are Completing this book:
• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after you have completed this module.
Multiple Choice Questions
Select the BEST answer.
1. What file extension does a presentation file have?
1. .ipt
2. .idw
3. .iam
4. .iaf
5. .ipn
2. What is the term used in an assembly file that refers to the part files linked to the assembly?
1. link
2. location
3. indicator
4. source
5. reference
3. What does the symbol “<<>>” signify in a dimension text?
1. A reference dimension.
2. The actual dimension number is a model or drawing dimension size.
3. The text size.
4. The dimension units of the model or drawing dimension.
5. That there is no dimension.
4. What is the name of first view you create on a drawing that controls the scale, orientation and location of the orthographical views projected from it?
1. Section View
2. Multiview
3. Projected View
4. Base view
5. Orthographic view
5. What command is used to get the model dimensions for a view?
1. GET DIMENSION
2. GENERAL DIMENSION
3. RETRIEVE DIMENSION
4. RECOVER DIMENSION
5. OBTAIN DIMENSION
6. What is the minimum and maximum number of drawing sheets that can exist in a single drawing file?
1. Minimum – 1 Maximum – none
2. Minimum – 1 Maximum – 10
3. Minimum – 0 Maximum – none
4. Minimum – 1 Maximum – 100
5. Minimum – 0 Maximum – 10
7. What file extension does a drawing file have?
1. .ipt
2. .idw
3. .iam
4. .iaf
5. .ipn
8. What is the method of the construction called when an assembly file is created from a series of part files that were previously created and saved in their own .IPT file?
1. Part Assembly
2. Bottom-up Assembly
3. IPT Assembly
4. Top-down Assembly
5. Series Assembly
9. What is the term used to describe the distances that the parts are moved from the grounded part in an explode assembly file?
1. Distance
2. Exploded
3. Trails
4. Animation
5. Tweak
10. What file extension does an assembly file have?
1. .ipt
2. .idw
3. .iam
4. .iaf
5. .ipn
Lab Exercise 26-1
Time allowed: 6 hours.
Part Name Project Units Template Color Material
Inventor Lab 26-1 Inventor Course Inches See Below See Below See Below
Step 1
Create the following parts. Each part must have its own file and constructed as follows:
A Project the Center Point onto the Base plane.
B Select your own location for X0Y0Z0.
C Draw the necessary sketches and extrude or revolve them to produce the solid models. Apply all of the necessary geometrical and dimensional constraints to maintain the objects shape and size. All sketches must be fully constrained.
D Apply the colour and material shown.
E Ensure that you draw each part in the correct orientation so that they can be easily assembled together. The Home view for each part will help you. (Figure Step 1A, 1B, and 1C)
Part: Base
Part Name: Inventor Lab 26-1A
Template: English-Modules Part (in).ipt
Color: Steel – Polished
Material: Stainless Steel
Part: Adjustment Shaft
Part Name: Inventor Lab 26-1B
Template: English-Modules Part (in).ipt
Color: Brass – Satin
Material: Soft Yellow Brass (Figure Step 1D, 1E, and 1F)
Part: Adjusting Nut
Part Name: Inventor Lab 26-1C
Template: English-Modules Part (in).ipt
Color: Nickel
Material: Non-Alloy Steel (Figure Step 1G and 1H)
Note: Knurl the outside of the nut.
Part: V-Shaft
Part Name: Inventor Lab 26-1D
Template: English-Modules Part (in).ipt
Color: Chrome – Polished Blue
Material: Stainless Steel (Figure Step 1J and 1K)
Part: Set Screw
Part Name: Inventor Lab 26-1E
Template: English-Modules Part (in).ipt
Color: Steel – Polished
Material: Steel (Figure Step 1L, 1M, and 1N)
Part: Bolt
Part Name: Inventor Lab 26-1F
Template: English-Modules Part (in).ipt
Color: Metal-AL-6061 – Machined
Material: Steel (Figure Step 1P and 1Q)
Part: Washer
Part Name: Inventor Lab 26-1G
Template: English-Modules Part (in).ipt
Color: Metal-AL-6061 – Machined
Material: Steel (Figure Step 1R and 1S)
Part: Nut
Part Name: Inventor Lab 26-1H
Template: English-Modules Part (in).ipt
Color: Metal-AL-6061 – Machined
Material: Steel (Figure Step 1T and 1U)
Step 2
Assemble the parts that you created in Step 1 to create the Machine Jack assembly as shown in figures below. There are two washers, one above and one below the base. The washer under the base should be assembled with 0.5 inches offset from the bottom of the base. Save the assembly using the following name:
Assembly: Machine Jack
Assembly Name: Inventor Lab 26-2A
Template: English-Modules Assembly (in).iam (Figure Step 2A and 2B)
Step 3
With the assembly file: Inventor Lab 26-2A.iam as the active file, save a copy of it naming it: Inventor Lab 26-2B.iam.
Step 4
Open the assembly file: Inventor Lab 26-2B.iam that you just copied. Change the colour of the Base and the Adjusting Nut in the assembly file to Clear – Blue as shown in the figures below.
Assembly: Machine Jack
Assembly Name: Inventor Lab 26-2B
Template: N/A (Figure Step 4A and 4B)
Step 5
Create a presentation file using the assembly file Inventor Lab 26-2A. Tweak it to match as close as you can to Figure Step 5.
Step 6
Set the animation Interval to 20 and the Repetitions to 2. Test the animation.
Presentation: Machine Jack
Presentation Name: Inventor Lab 26-2A
Template: N/A
Step 7
Create the following drawing as follows:
A Create one drawing file complete with two sheets as shown in Figure 4A, 4B and Figure 7A, 7B.
B Create the same views shown in the drawings.
C If the scale is not indicated, set it to full scale or 1:1.
D Save the drawing file with the drawing name: Inventor Lab 26-1.idw Figure Step 5
E Complete the titleblock in both drawings sheets.
Drawing Name: Inventor Lab 26-1.idw
Template: English-Modules Drawing ANSI (in).idw
Sheet: 1
Part: Base
Drawing Size: C
Part Name: Inventor Lab 26-1A.ipt (Figure Step 7A and 7B)
Sheet: 2
Part: Post
Drawing Size: A
Part Name: Inventor Lab 26-1D.ipt (Figure Step 7C and 7D) | textbooks/workforce/Drafting_and_Design_Technology/Introduction_to_Drafting_and_Autodesk_Inventor_(Baumback)/05%3A_Part_5/5.05%3A_Module_26_Competency_Test_No._5_Open_Book.txt |
• 1.1: From Electric to Electronic
This third volume of the book series Lessons In Electric Circuits makes a departure from the former two in that the transition between electric circuits and electronic circuits is formally crossed. Electric circuits are connections of conductive wires and other devices whereby the uniform flow of electrons occurs. Electronic circuits add a new dimension to electric circuits in that some means of control is exerted over the flow of electrons by another electrical signal, either a voltage or a cur
• 1.2: Active Versus Passive Devices
An active device is any type of circuit component with the ability to electrically control electron flow (electricity controlling electricity). In order for a circuit to be properly called electronic, it must contain at least one active device. Components incapable of controlling current by means of another electrical signal are called passive devices.
• 1.3: Amplifiers
The practical benefit of active devices is their amplifying ability. Whether the device in question be voltage-controlled or current-controlled, the amount of power required of the controlling signal is typically far less than the amount of power available in the controlled current. In other words, an active device doesn’t just allow electricity to control electricity; it allows a small amount of electricity to control a large amount of electricity.
• 1.4: Amplifier Gain
Because amplifiers have the ability to increase the magnitude of an input signal, it is useful to be able to rate an amplifier’s amplifying ability in terms of an output/input ratio. The technical term for an amplifier’s output/input magnitude ratio is gain. As a ratio of equal units (power out / power in, voltage out / voltage in, or current out / current in), gain is naturally a unitless measurement.
• 1.5: Decibels
In its simplest form, an amplifier’s gain is a ratio of output over input. Like all ratios, this form of gain is unitless. However, there is an actual unit intended to represent gain, and it is called the bel. As a unit, the bel was actually devised as a convenient way to represent power loss in telephone system wiring rather than gain in amplifiers. The unit’s name is derived from Alexander Graham Bell, the famous Scottish inventor whose work was instrumental in developing telephone systems.
• 1.6: Absolute dB scales
It is also possible to use the decibel as a unit of absolute power, in addition to using it as an expression of power gain or loss. A common example of this is the use of decibels as a measurement of sound pressure intensity. In cases like these, the measurement is made in reference to some standardized power level defined as 0 dB. For measurements of sound pressure, 0 dB is loosely defined as the lower threshold of human hearing, objectively quantified as 1 picowatt of sound power per square me
• 1.7: Attenuators
Attenuators are passive devices. It is convenient to discuss them along with decibels. Attenuators weaken or attenuate the high level output of a signal generator, for example, to provide a lower level signal for something like the antenna input of a sensitive radio receiver. The attenuator could be built into the signal generator, or be a stand-alone device. It could provide a fixed or adjustable amount of attenuation. An attenuator section can provide isolate a source from a troublesome load.
01: Amplifiers and Active Devices
In and of itself, the control of electron flow is nothing new to the student of electric circuits. Switches control the flow of electrons, as do potentiometers, especially when connected as variable resistors (rheostats). Neither the switch nor the potentiometer should be new to your experience by this point in your study. The threshold marking the transition from electric to electronic, then, is defined by how the flow of electrons is controlled rather than whether or not any form of control exists in a circuit. Switches and rheostats control the flow of electrons according to the positioning of a mechanical device, which is actuated by some physical force external to the circuit. In electronics, however, we are dealing with special devices able to control the flow of electrons according to another flow of electrons, or by the application of a static voltage. In other words, in an electronic circuit, electricity is able to control electricity.
The historic precursor to the modern electronics era was invented by Thomas Edison in 1880 while developing the electric incandescent lamp. Edison found that a small current passed from the heated lamp filament to a metal plate mounted inside the vacuum envelope. (Figure below (a)) Today this is known as the “Edison effect”. Note that the battery is only necessary to heat the filament. Electrons would still flow if a non-electrical heat source was used.
(a) Edison effect, (b) Fleming valve or vacuum diode, (c) DeForest audion triode vacuum tube amplifier.
By 1904 Marconi Wireless Company adviser John Flemming found that an externally applied current (plate battery) only passed in one direction from filament to plate (Figure above (b)), but not the reverse direction (not shown). This invention was the vacuum diode, used to convert alternating currents to DC. The addition of a third electrode by Lee DeForest (Figure above (c)) allowed a small signal to control the larger electron flow from filament to plate.
Historically, the era of electronics began with the invention of the Audion tube, a device controlling the flow of an electron stream through a vacuum by the application of a small voltage between two metal structures within the tube. A more detailed summary of so-called electron tube or vacuum tube technology is available in the last chapter of this volume for those who are interested.
Electronics technology experienced a revolution in 1948 with the invention of the transistor. This tiny device achieved approximately the same effect as the Audion tube, but in a vastly smaller amount of space and with less material. Transistors control the flow of electrons through solid semiconductor substances rather than through a vacuum, and so transistor technology is often referred to as solid-state electronics. | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/01%3A_Amplifiers_and_Active_Devices/1.01%3A_From_Electric_to_Electronic.txt |
An active device is any type of circuit component with the ability to electrically control electron flow (electricity controlling electricity). In order for a circuit to be properly called electronic, it must contain at least one active device. Components incapable of controlling current by means of another electrical signal are called passive devices. Resistors, capacitors, inductors, transformers, and even diodes are all considered passive devices. Active devices include, but are not limited to, vacuum tubes, transistors, silicon-controlled rectifiers (SCRs), and TRIACs. A case might be made for the saturable reactor to be defined as an active device, since it is able to control an AC current with a DC current, but I’ve never heard it referred to as such. The operation of each of these active devices will be explored in later chapters of this volume.
All active devices control the flow of electrons through them. Some active devices allow a voltage to control this current while other active devices allow another current to do the job. Devices utilizing a static voltage as the controlling signal are, not surprisingly, called voltage-controlled devices. Devices working on the principle of one current controlling another current are known as current-controlled devices. For the record, vacuum tubes are voltage-controlled devices while transistors are made as either voltage-controlled or current controlled types. The first type of transistor successfully demonstrated was a current-controlled device.
1.03: Amplifiers
Because of this disparity between controlling and controlled powers, active devices may be employed to govern a large amount of power (controlled) by the application of a small amount of power (controlling). This behavior is known as amplification.
It is a fundamental rule of physics that energy can neither be created nor destroyed. Stated formally, this rule is known as the Law of Conservation of Energy, and no exceptions to it have been discovered to date. If this Law is true—and an overwhelming mass of experimental data suggests that it is—then it is impossible to build a device capable of taking a small amount of energy and magically transforming it into a large amount of energy. All machines, electric and electronic circuits included, have an upper efficiency limit of 100 percent. At best, power out equals power in as in Figure below.
The power output of a machine can approach, but never exceed, the power input for 100% efficiency as an upper limit.
Usually, machines fail even to meet this limit, losing some of their input energy in the form of heat which is radiated into surrounding space and therefore not part of the output energy stream. (Figure below)
A realistic machine most often loses some of its input energy as heat in transforming it into the output energy stream.
Many people have attempted, without success, to design and build machines that output more power than they take in. Not only would such a perpetual motion machine prove that the Law of Conservation of Energy was not a Law after all, but it would usher in a technological revolution such as the world has never seen, for it could power itself in a circular loop and generate excess power for “free”. (Figure below)
Hypothetical “perpetual motion machine” powers itself?
Despite much effort and many unscrupulous claims of “free energy” or over-unity machines, not one has ever passed the simple test of powering itself with its own energy output and generating energy to spare.
There does exist, however, a class of machines known as amplifiers, which are able to take in small-power signals and output signals of much greater power. The key to understanding how amplifiers can exist without violating the Law of Conservation of Energy lies in the behavior of active devices.
Because active devices have the ability to control a large amount of electrical power with a small amount of electrical power, they may be arranged in circuit so as to duplicate the form of the input signal power from a larger amount of power supplied by an external power source. The result is a device that appears to magically magnify the power of a small electrical signal (usually an AC voltage waveform) into an identically-shaped waveform of larger magnitude. The Law of Conservation of Energy is not violated because the additional power is supplied by an external source, usually a DC battery or equivalent. The amplifier neither creates nor destroys energy, but merely reshapes it into the waveform desired as shown in Figure below.
While an amplifier can scale a small input signal to large output, its energy source is an external power supply.
In other words, the current-controlling behavior of active devices is employed to shape DC power from the external power source into the same waveform as the input signal, producing an output signal of like shape but different (greater) power magnitude. The transistor or other active device within an amplifier merely forms a larger copy of the input signal waveform out of the “raw” DC power provided by a battery or other power source.
Amplifiers, like all machines, are limited in efficiency to a maximum of 100 percent. Usually, electronic amplifiers are far less efficient than that, dissipating considerable amounts of energy in the form of waste heat. Because the efficiency of an amplifier is always 100 percent or less, one can never be made to function as a “perpetual motion” device.
The requirement of an external source of power is common to all types of amplifiers, electrical and non-electrical. A common example of a non-electrical amplification system would be power steering in an automobile, amplifying the power of the driver’s arms in turning the steering wheel to move the front wheels of the car. The source of power necessary for the amplification comes from the engine. The active device controlling the driver’s “input signal” is a hydraulic valve shuttling fluid power from a pump attached to the engine to a hydraulic piston assisting wheel motion. If the engine stops running, the amplification system fails to amplify the driver’s arm power and the car becomes very difficult to turn.
1.04: Amplifier Gain
The Voltage Gain
Because amplifiers have the ability to increase the magnitude of an input signal, it is useful to be able to rate an amplifier’s amplifying ability in terms of an output/input ratio. The technical term for an amplifier’s output/input magnitude ratio is gain. As a ratio of equal units (power out / power in, voltage out / voltage in, or current out / current in), gain is naturally a unitless measurement.
Mathematically, gain is symbolized by the capital letter “A”.
How to Calculate Voltage Gain
For example, if an amplifier takes in an AC voltage signal measuring 2 volts RMS and outputs an AC voltage of 30 volts RMS, it has an AC voltage gain of 30 divided by 2, or 15:
Correspondingly, if we know the gain of an amplifier and the magnitude of the input signal, we can calculate the magnitude of the output. For example, if an amplifier with an AC current gain of 3.5 is given an AC input signal of 28 mA RMS, the output will be 3.5 times 28 mA or 98 mA:
In the last two examples, I specifically identified the gains and signal magnitudes in terms of “AC”. This was intentional, and illustrates an important concept: electronic amplifiers often respond differently to AC and DC input signals and may amplify them to different extents.
Another way of saying this is that amplifiers often amplify changes or variations in input signal magnitude (AC) at a different ratio than steady input signal magnitudes (DC). The specific reasons for this are too complex to explain at this time, but the fact of the matter is worth mentioning.
If gain calculations are to be carried out, it must first be understood what type of signals and gains are being dealt with, AC or DC.
Electrical Amplifier Gains: Voltage, Current, and/or Power
Electrical amplifier gains may be expressed in terms of voltage, current, and/or power in both AC and DC.
A summary of gain definitions is as follows:
The triangle-shaped “delta” symbol (Δ) represents change in mathematics, so “ΔVoutput / ΔVinput” means “change in output voltage divided by change in input voltage,” or more simply, “AC output voltage divided by AC input voltage”:
If multiple amplifiers are staged, their respective gains form an overall gain equal to the product (multiplication) of the individual gains. In the figure below, if a 1 V signal were applied to the input of the gain of 3 amplifier, a 3 V signal out of the first amplifier would be further amplified by a gain of 5 at the second stage yielding 15 V at the final output.
The gain of a chain of cascaded amplifiers is the product of the individual gains. | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/01%3A_Amplifiers_and_Active_Devices/1.02%3A_Active_Versus_Passive_Devices.txt |
The Bel is Used to Represent Gain
In its simplest form, an amplifier’s gain is a ratio of output over input. Like all ratios, this form of gain is unitless. However, there is an actual unit intended to represent gain, and it is called the bel.
As a unit, the bel was actually devised as a convenient way to represent power loss in telephone system wiring rather than gain in amplifiers. The unit’s name is derived from Alexander Graham Bell, the famous Scottish inventor whose work was instrumental in developing telephone systems. Originally, the bel represented the amount of signal power loss due to resistance over a standard length of electrical cable. Now, it is defined in terms of the common (base 10) logarithm of a power ratio (output power divided by input power):
The Bel is Nonlinear
Because the bel is a logarithmic unit, it is nonlinear. To give you an idea of how this works, consider the following table of figures, comparing power losses and gains in bels versus simple ratios:
Moving from the Bel to the Decibel
It was later decided that the bel was too large of a unit to be used directly, and so it became customary to apply the metric prefix deci (meaning 1/10) to it, making it decibels, or dB. Now, the expression “dB” is so common that many people do not realize it is a combination of “deci-” and “-bel,” or that there even is such a unit as the “bel.” To put this into perspective, here is another table contrasting power gain/loss ratios against decibels:
As a logarithmic unit, this mode of power gain expression covers a wide range of ratios with a minimal span in figures. It is reasonable to ask, “why did anyone feel the need to invent a logarithmic unit for electrical signal power loss in a telephone system?” The answer is related to the dynamics of human hearing, the perceptive intensity of which is logarithmic in nature.
Human Hearing is Nonlinear
Human hearing is highly nonlinear: in order to double the perceived intensity of a sound, the actual sound power must be multiplied by a factor of ten. Relating telephone signal power loss in terms of the logarithmic “bel” scale makes perfect sense in this context: a power loss of 1 bel translates to a perceived sound loss of 50 percent, or 1/2. A power gain of 1 bel translates to a doubling in the perceived intensity of the sound.
Other Logarithmic Scale Examples: Richter Scale and Chemical pH
An almost perfect analogy to the bel scale is the Richter scale used to describe earthquake intensity: a 6.0 Richter earthquake is 10 times more powerful than a 5.0 Richter earthquake; a 7.0 Richter earthquake 100 times more powerful than a 5.0 Richter earthquake; a 4.0 Richter earthquake is 1/10 as powerful as a 5.0 Richter earthquake, and so on. The measurement scale for chemical pH is likewise logarithmic, a difference of 1 on the scale is equivalent to a tenfold difference in hydrogen ion concentration of a chemical solution. An advantage of using a logarithmic measurement scale is the tremendous range of expression afforded by a relatively small span of numerical values, and it is this advantage which secures the use of Richter numbers for earthquakes and pH for hydrogen ion activity.
Using the Bel to Express System Gains and Losses
Another reason for the adoption of the bel as a unit for gain is for simple expression of system gains and losses. Consider the last system example (Figure above) where two amplifiers were connected tandem to amplify a signal. The respective gain for each amplifier was expressed as a ratio, and the overall gain for the system was the product (multiplication) of those two ratios:
If these figures represented power gains, we could directly apply the unit of bels to the task of representing the gain of each amplifier, and of the system altogether. (Figure below)
Power gain in bels is additive: 0.477 B + 0.699 B = 1.176 B.
Close inspection of these gain figures in the unit of “bel” yields a discovery: they’re additive. Ratio gain figures are multiplicative for staged amplifiers, but gains expressed in bels add rather than multiply to equal the overall system gain. The first amplifier with its power gain of 0.477 B adds to the second amplifier’s power gain of 0.699 B to make a system with an overall power gain of 1.176 B.
Recalculating for decibels rather than bels, we notice the same phenomenon. (Figure below)
Gain of amplifier stages in decibels is additive: 4.77 dB + 6.99 dB = 11.76 dB.
To those already familiar with the arithmetic properties of logarithms, this is no surprise. It is an elementary rule of algebra that the antilogarithm of the sum of two numbers’ logarithm values equals the product of the two original numbers. In other words, if we take two numbers and determine the logarithm of each, then add those two logarithm figures together, then determine the “antilogarithm” of that sum (elevate the base number of the logarithm—in this case, 10—to the power of that sum), the result will be the same as if we had simply multiplied the two original numbers together. This algebraic rule forms the heart of a device called a slide rule, an analog computer which could, among other things, determine the products and quotients of numbers by addition (adding together physical lengths marked on sliding wood, metal, or plastic scales). Given a table of logarithm figures, the same mathematical trick could be used to perform otherwise complex multiplications and divisions by only having to do additions and subtractions, respectively. With the advent of high-speed, handheld, digital calculator devices, this elegant calculation technique virtually disappeared from popular use. However, it is still important to understand when working with measurement scales that are logarithmic in nature, such as the bel (decibel) and Richter scales.
When converting a power gain from units of bels or decibels to a unitless ratio, the mathematical inverse function of common logarithms is used: powers of 10, or the antilog.
Converting decibels into unitless ratios for power gain is much the same, only a division factor of 10 is included in the exponent term:
Example: Power into an amplifier is 1 Watt, the power out is 10 Watts. Find the power gain in dB.
Example: Find the power gain ratio AP(ratio) = (PO / PI) for a 20 dB Power gain.
Because the bel is fundamentally a unit of power gain or loss in a system, voltage or current gains and losses don’t convert to bels or dB in quite the same way. When using bels or decibels to express a gain other than power, be it voltage or current, we must perform the calculation in terms of how much power gain there would be for that amount of voltage or current gain. For a constant load impedance, a voltage or current gain of 2 equates to a power gain of 4 (22); a voltage or current gain of 3 equates to a power gain of 9 (32). If we multiply either voltage or current by a given factor, then the power gain incurred by that multiplication will be the square of that factor. This relates back to the forms of Joule’s Law where power was calculated from either voltage or current, and resistance:
Thus, when translating a voltage or current gain ratio into a respective gain in terms of the bel unit, we must include this exponent in the equation(s):
The same exponent requirement holds true when expressing voltage or current gains in terms of decibels:
However, thanks to another interesting property of logarithms, we can simplify these equations to eliminate the exponent by including the “2” as a multiplying factor for the logarithm function. In other words, instead of taking the logarithm of the square of the voltage or current gain, we just multiply the voltage or current gain’s logarithm figure by 2 and the final result in bels or decibels will be the same:
The process of converting voltage or current gains from bels or decibels into unitless ratios is much the same as it is for power gains:
Here are the equations used for converting voltage or current gains in decibels into unitless ratios:
While the bel is a unit naturally scaled for power, another logarithmic unit has been invented to directly express voltage or current gains/losses, and it is based on the natural logarithm rather than the commonlogarithm as bels and decibels are. Called the neper, its unit symbol is “Np; though, lower-case “n” may be encountered.
For better or for worse, neither the neper nor its attenuated cousin, the decineper, is popularly used as a unit in American engineering applications.
Example: The voltage into a 600 Ω audio line amplifier is 10 mV, the voltage across a 600 Ω load is 1 V. Find the power gain in dB.
Example: Find the voltage gain ratio AV(ratio) = (VO / VI) for a 20 dB gain amplifier having a 50 Ω input and out impedance.
A Review of the Decibel
• Gains and losses may be expressed in terms of a unitless ratio, or in the unit of bels (B) or decibels (dB). A decibel is literally a deci-bel: one-tenth of a bel.
• The bel is fundamentally a unit for expressing power gain or loss. To convert a power ratio to either bels or decibels, use one of these equations:
• When using the unit of the bel or decibel to express a voltage or current ratio, it must be cast in terms of an equivalent power ratio. Practically, this means the use of different equations, with a multiplication factor of 2 for the logarithm value corresponding to an exponent of 2 for the voltage or current gain ratio:
• To convert a decibel gain into a unitless ratio gain, use one of these equations:
• A gain (amplification) is expressed as a positive bel or decibel figure. A loss (attenuation) is expressed as a negative bel or decibel figure. Unity gain (no gain or loss; ratio = 1) is expressed as zero bels or zero decibels.
• When calculating overall gain for an amplifier system composed of multiple amplifier stages, individual gain ratios are multiplied to find the overall gain ratio. Bel or decibel figures for each amplifier stage, on the other hand, are added together to determine overall gain. | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/01%3A_Amplifiers_and_Active_Devices/1.05%3A_Decibels.txt |
A sound measuring 40 dB on the decibel sound scale would be 104 times greater than the threshold of hearing. A 100 dB sound would be 1010 (ten billion) times greater than the threshold of hearing.
Because the human ear is not equally sensitive to all frequencies of sound, variations of the decibel sound-power scale have been developed to represent physiologically equivalent sound intensities at different frequencies. Some sound intensity instruments were equipped with filter networks to give disproportionate indications across the frequency scale, the intent of which to better represent the effects of sound on the human body. Three filtered scales became commonly known as the “A,” “B,” and “C” weighted scales. Decibel sound intensity indications measured through these respective filtering networks were given in units of dBA, dBB, and dBC. Today, the “A-weighted scale” is most commonly used for expressing the equivalent physiological impact on the human body, and is especially useful for rating dangerously loud noise sources.
Another standard-referenced system of power measurement in the unit of decibels has been established for use in telecommunications systems. This is called the dBm scale. (Figure below) The reference point, 0 dBm, is defined as 1 milliwatt of electrical power dissipated by a 600 Ω load. According to this scale, 10 dBm is equal to 10 times the reference power, or 10 milliwatts; 20 dBm is equal to 100 times the reference power, or 100 milliwatts. Some AC voltmeters come equipped with a dBm range or scale (sometimes labeled “DB”) intended for use in measuring AC signal power across a 600 Ω load. 0 dBm on this scale is, of course, elevated above zero because it represents something greater than 0 (actually, it represents 0.7746 volts across a 600 Ω load, voltage being equal to the square root of power times resistance; the square root of 0.001 multiplied by 600). When viewed on the face of an analog meter movement, this dBm scale appears compressed on the left side and expanded on the right in a manner not unlike a resistance scale, owing to its logarithmic nature.
Radio frequency power measurements for low level signals encountered in radio receivers use dBm measurements referenced to a 50 Ω load. Signal generators for the evaluation of radio receivers may output an adjustable dBm rated signal. The signal level is selected by a device called an attenuator, described in the next section.
Absolute power levels in dBm (decibels referenced to 1 milliwatt).
An adaptation of the dBm scale for audio signal strength is used in studio recording and broadcast engineering for standardizing volume levels, and is called the VU scale. VU meters are frequently seen on electronic recording instruments to indicate whether or not the recorded signal exceeds the maximum signal level limit of the device, where significant distortion will occur. This “volume indicator” scale is calibrated in according to the dBm scale, but does not directly indicate dBm for any signal other than steady sine-wave tones. The proper unit of measurement for a VU meter is volume units.
When relatively large signals are dealt with, and an absolute dB scale would be useful for representing signal level, specialized decibel scales are sometimes used with reference points greater than the 1 mW used in dBm. Such is the case for the dBW scale, with a reference point of 0 dBW established at 1 Watt. Another absolute measure of power called the dBk scale references 0 dBk at 1 kW, or 1000 Watts.
Review
• The unit of the bel or decibel may also be used to represent an absolute measurement of power rather than just a relative gain or loss. For sound power measurements, 0 dB is defined as a standardized reference point of power equal to 1 picowatt per square meter. Another dB scale suited for sound intensity measurements is normalized to the same physiological effects as a 1000 Hz tone, and is called the dBA scale. In this system, 0 dBA is defined as any frequency sound having the same physiological equivalence as a 1 picowatt-per-square-meter tone at 1000 Hz.
• An electrical dB scale with an absolute reference point has been made for use in telecommunications systems. Called the dBm scale, its reference point of 0 dBm is defined as 1 milliwatt of AC signal power dissipated by a 600 Ω load.
• A VU meter reads audio signal level according to the dBm for sine-wave signals. Because its response to signals other than steady sine waves is not the same as true dBm, its unit of measurement is volume units.
• dB scales with greater absolute reference points than the dBm scale have been invented for high-power signals. The dBW scale has its reference point of 0 dBW defined as 1 Watt of power. The dBk scale sets 1 kW (1000 Watts) as the zero-point reference. | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/01%3A_Amplifiers_and_Active_Devices/1.06%3A_Absolute_dB_scales.txt |
What are Attenuators?
Attenuators are passive devices. It is convenient to discuss them along with decibels. Attenuators weaken or attenuate the high level output of a signal generator, for example, to provide a lower level signal for something like the antenna input of a sensitive radio receiver. (Figure below) The attenuator could be built into the signal generator, or be a stand-alone device. It could provide a fixed or adjustable amount of attenuation. An attenuator section can also provide isolation between a source and a troublesome load.
Constant impedance attenuator is matched to source impedance ZI and load impedance ZO. For radio frequency equipment Z is 50 Ω.
In the case of a stand-alone attenuator, it must be placed in series between the signal source and the load by breaking open the signal path as shown in Figure above. In addition, it must match both the source impedance ZI and the load impedance ZO, while providing a specified amount of attenuation. In this section we will only consider the special, and most common, case where the source and load impedances are equal. Not considered in this section, unequal source and load impedances may be matched by an attenuator section. However, the formulation is more complex.
Common configurations are the T and Π networks shown in Figure above Multiple attenuator sections may be cascaded when even weaker signals are needed as in Figure below.
Decibels
Voltage ratios, as used in the design of attenuators are often expressed in terms of decibels. The voltage ratio (K below) must be derived from the attenuation in decibels. Power ratios expressed as decibels are additive. For example, a 10 dB attenuator followed by a 6 dB attenuator provides 16dB of attenuation overall.
$\text{ 10 db + 6db} = \text{ 16 db}$
Changing sound levels are perceptible roughly proportional to the logarithm of the power ratio ($P_I / P_o$).
$\text{sound level} = \log_{10} \dfrac{P_I}{P_o}$
A change of 1 dB in sound level is barely perceptible to a listener, while 2 db is readily perceptible. An attenuation of 3 dB corresponds to cutting power in half, while a gain of 3 db corresponds to a doubling of the power level. A gain of -3 dB is the same as an attenuation of +3 dB, corresponding to half the original power level.
The power change in decibels in terms of power ratio is:
Assuming that the load RI at PI is the same as the load resistor RO at PO (RI = RO), the decibels may be derived from the voltage ratio (VI / VO) or current ratio (II / IO):
The two most often used forms of the decibel equation are:
We will use the latter form, since we need the voltage ratio. Once again, the voltage ratio form of equation is only applicable where the two corresponding resistors are equal. That is, the source and load resistance need to be equal.
Example: Power into an attenuator is 10 Watts, the power out is 1 Watt. Find the attenuation in dB.
Example: Find the voltage attenuation ratio (K= (VI / VO)) for a 10 dB attenuator.
Example: Power into an attenuator is 100 milliwatts, the power out is 1 milliwatt. Find the attenuation in dB.
Example: Find the voltage attenuation ratio (K= (VI / VO)) for a 20 dB attenuator.
T-section attenuator
The T and Π attenuators must be connected to a Z source and Z load impedance. The Z-(arrows) pointing away from the attenuator in the figure below indicate this. The Z-(arrows) pointing toward the attenuator indicates that the impedance seen looking into the attenuator with a load Z on the opposite end is Z, Z=50 Ω for our case. This impedance is a constant (50 Ω) with respect to attenuation– impedance does not change when attenuation is changed.
The table in Figure below lists resistor values for the T and Π attenuators to match a 50 Ω source/ load, as is the usual requirement in radio frequency work.
Telephone utility and other audio work often requires matching to 600 Ω. Multiply all R values by the ratio (600/50) to correct for 600 Ω matching. Multiplying by 75/50 would convert table values to match a 75 Ω source and load.
Formulas for T-section attenuator resistors, given K, the voltage attenuation ratio, and ZI = ZO = 50 Ω.
The amount of attenuation is customarily specified in dB (decibels). Though, we need the voltage (or current) ratio K to find the resistor values from equations. See the dB/20 term in the power of 10 term for computing the voltage ratio K from dB, above.
The T (and below Π) configurations are most commonly used as they provide bidirectional matching. That is, the attenuator input and output may be swapped end for end and still match the source and load impedances while supplying the same attenuation.
Disconnecting the source and looking in to the right at VI, we need to see a series parallel combination of R1, R2, R1, and Z looking like an equivalent resistance of ZIN, the same as the source/load impedance Z: (a load of Z is connected to the output.)
For example, substitute the 10 dB values from the 50 Ω attenuator table for R1 and R2 as shown in Figure below.
This shows us that we see 50 Ω looking right into the example attenuator (Figure below) with a 50 Ω load.
Replacing the source generator, disconnecting load Z at VO, and looking in to the left, should give us the same equation as above for the impedance at VO, due to symmetry. Moreover, the three resistors must be values which supply the required attenuation from input to output. This is accomplished by the equations for R1 and R2 above as applied to the T-attenuator below.
10 dB T-section attenuator for insertion between a 50 Ω source and load.
PI-section attenuator
The table in Figure below lists resistor values for the Π attenuator matching a 50 Ω source/ load at some common attenuation levels. The resistors corresponding to other attenuation levels may be calculated from the equations.
Formulas for Π-section attenuator resistors, given K, the voltage attenuation ratio, and ZI = ZO = 50 Ω.
The above apply to the π-attenuator below.
What resistor values would be required for both the Π attenuators for 10 dB of attenuation matching a 50 Ω source and load?
10 dB Π-section attenuator example for matching a 50 Ω source and load.
The 10 dB corresponds to a voltage attenuation ratio of K=3.16 in the next to last line of the above table. Transfer the resistor values in that line to the resistors on the schematic diagram in Figure above.
L-section attenuator
The table in Figure below lists resistor values for the L attenuators to match a 50 Ω source/ load. The table in Figure below lists resistor values for an alternate form. Note that the resistor values are not the same.
L-section attenuator table for 50 Ω source and load impedance.
The above apply to the L attenuator below.
Alternate form L-section attenuator table for 50 Ω source and load impedance.
Bridged T attenuator
The table in Figure below lists resistor values for the bridged T attenuators to match a 50 Ω source and load. The bridged-T attenuator is not often used. Why not?
Formulas and abbreviated table for bridged-T attenuator section, Z = 50 Ω.
Cascaded sections
Attenuator sections can be cascaded as in Figure below for more attenuation than may be available from a single section. For example two 10 db attenuators may be cascaded to provide 20 dB of attenuation, the dB values being additive. The voltage attenuation ratio K or VI/VO for a 10 dB attenuator section is 3.16. The voltage attenuation ratio for the two cascaded sections is the product of the two Ks or 3.16x3.16=10 for the two cascaded sections.
Cascaded attenuator sections: dB attenuation is additive.
Variable attenuation can be provided in discrete steps by a switched attenuator. The example Figure below, shown in the 0 dB position, is capable of 0 through 7 dB of attenuation by additive switching of none, one or more sections.
Switched attenuator: attenuation is variable in discrete steps.
The typical multi section attenuator has more sections than the above figure shows. The addition of a 3 or 8 dB section above enables the unit to cover to 10 dB and beyond. Lower signal levels are achieved by the addition of 10 dB and 20 dB sections, or a binary multiple 16 dB section.
RF attenuators
For radio frequency (RF) work (<1000 Mhz), the individual sections must be mounted in shielded compartments to thwart capacitive coupling if lower signal levels are to be achieved at the highest frequencies. The individual sections of the switched attenuators in the previous section are mounted in shielded sections. Additional measures may be taken to extend the frequency range to beyond 1000 Mhz. This involves construction from special shaped lead-less resistive elements.
Coaxial T-attenuator for radio frequency work.
A coaxial T-section attenuator consisting of resistive rods and a resistive disk is shown in Figure above. This construction is usable to a few gigahertz. The coaxial Π version would have one resistive rod between two resistive disks in the coaxial line as in Figure below.
Coaxial Π-attenuator for radio frequency work.
RF connectors, not shown, are attached to the ends of the above T and Π attenuators. The connectors allow individual attenuators to be cascaded, in addition to connecting between a source and load. For example, a 10 dB attenuator may be placed between a troublesome signal source and an expensive spectrum analyzer input. Even though we may not need the attenuation, the expensive test equipment is protected from the source by attenuating any overvoltage.
Summary: Attenuators
• An attenuator reduces an input signal to a lower level.
• The amount of attenuation is specified in decibels (dB). Decibel values are additive for cascaded attenuator sections.
• dB from power ratio: dB = 10 log10(PI / PO)
• dB from voltage ratio: dB = 20 log10(VI / VO)
• T and Π section attenuators are the most common circuit configurations. | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/01%3A_Amplifiers_and_Active_Devices/1.07%3A_Attenuators.txt |
• 2.1: Introduction to Solid-state Device Theory
This chapter will cover the physics behind the operation of semiconductor devices and show how these principles are applied in several different types of semiconductor devices. Subsequent chapters will deal primarily with the practical aspects of these devices in circuits and omit theory as much as possible.
• 2.2: Quantum Physics
• 2.3: Valence and Crystal Structure
Valence: The electrons in the outer most shell, or valence shell, are known as valence electrons. These valence electrons are responsible for the chemical properties of the chemical elements. It is these electrons which participate in chemical reactions with other elements. An over simplified chemistry rule applicable to simple reactions is that atoms try to form a complete outer shell of 8 electrons (two for the L shell). Atoms may give away a few electrons to expose an underlying complete shel
• 2.4: Band Theory of Solids
Quantum physics describes the states of electrons in an atom according to the four-fold scheme of quantum numbers. The quantum numbers describe the allowable states electrons may assume in an atom. To use the analogy of an amphitheater, quantum numbers describe how many rows and seats are available. Individual electrons may be described by the combination of quantum numbers, like a spectator in an amphitheater assigned to a particular row and seat.
• 2.5: Electrons and “holes’’
Pure semiconductors are relatively good insulators as compared with metals, though not nearly as good as a true insulator like glass. To be useful in semiconductor applications, the intrinsic semiconductor (pure undoped semiconductor) must have no more than one impurity atom in 10 billion semiconductor atoms. This is analogous to a grain of salt impurity in a railroad boxcar of sugar. Impure, or dirty semiconductors are considerably more conductive, though not as good as metals. Why might this b
• 2.6: The P-N Junction
If a block of P-type semiconductor is placed in contact with a block of N-type semiconductor in Figure below(a), the result is of no value. We have two conductive blocks in contact with each other, showing no unique properties. The problem is two separate and distinct crystal bodies. The number of electrons is balanced by the number of protons in both blocks. Thus, neither block has any net charge.
• 2.7: Junction Diodes
There were some historic crude, but usable were some historic crude, but usable semiconductor rectifiers before high purity materials were available. Ferdinand Braun invented a lead sulfide, PbS, based point contact rectifier in 1874. Cuprous oxide rectifiers were used as power rectifiers in 1924. The forward voltage drop is 0.2 V. The linear characteristic curve perhaps is why Cu2O was used as a rectifier for the AC scale on D’Arsonval based multimeters. This diode is also photosensitive.
• 2.8: Bipolar Junction Transistors
The bipolar junction transistor (BJT) was named because its operation involves conduction by two carriers: electrons and holes in the same crystal. The first bipolar transistor was invented at Bell Labs by William Shockley, Walter Brattain, and John Bardeen so late in 1947 that it was not published until 1948. Thus, many texts differ as to the date of invention. Brattain fabricated a germanium point contact transistor, bearing some resemblance to a point contact diode. Within a month, Shockley h
• 2.9: Junction Field-effect Transistors
The field effect transistor was proposed by Julius Lilienfeld in US patents in 1926 and 1933 (1,900,018). Moreover, Shockley, Brattain, and Bardeen were investigating the field effect transistor in 1947. Though, the extreme difficulties sidetracked them into inventing the bipolar transistor instead. Shockley’s field effect transistor theory was published in 1952. However, the materials processing technology was not mature enough until 1960 when John Atalla produced a working device.
• 2.10: Insulated-gate Field-effect Transistors (MOSFET)
The insulated-gate field-effect transistor (IGFET), also known as the metal oxide field effect transistor (MOSFET), is a derivative of the field effect transistor (FET). Today, most transistors are of the MOSFET type as components of digital integrated circuits. Though discrete BJT’s are more numerous than discrete MOSFET’s. The MOSFET transistor count within an integrated circuit may approach hundreds of a million. The dimensions of individual MOSFET devices are under a micron, decreasing every
• 2.12: Semiconductor Manufacturing Techniques
The manufacture of only silicon based semiconductors is described in this section; most semiconductors are silicon. Silicon is particularly suitable for integrated circuits because it readily forms an oxide coating, useful in patterning integrated components like transistors.
• 2.13: Superconducting Devices
Superconducting devices, though not widely used, have some unique characteristics not available in standard semiconductor devices. High sensitivity with respect to amplification of electrical signals, detection of magnetic fields, and detection of light are prized applications. High-speed switching is also possible, though not applied to computers at this time. Conventional superconducting devices must be cooled to within a few degrees of 0 Kelvin (-273 o C). Though, work is proceeding at this t
• 2.15: Semiconductor Devices in SPICE
The SPICE (simulation program, integrated circuit emphesis) electronic simulation program provides circuit elements and models for semiconductors. The SPICE element names begin with d, q, j, or m correspond to diode, BJT, JFET and MOSFET elements, respectively. These elements are accompanied by corresponding “models” These models have extensive lists of parameters describing the device. Though, we do not list them here. In this section we provide a very brief listing of simple spice models for s
02: Solid-state Device Theory
“I think it is safe to say that no one understands quantum mechanics.”
—Physicist Richard P. Feynman
To say that the invention of semiconductor devices was a revolution would not be an exaggeration. Not only was this an impressive technological accomplishment, but it paved the way for developments that would indelibly alter modern society. Semiconductor devices made possible miniaturized electronics, including computers, certain types of medical diagnostic and treatment equipment, and popular telecommunication devices, to name a few applications of this technology.
But behind this revolution in technology stands an even greater revolution in general science: the field of quantum physics. Without this leap in understanding the natural world, the development of semiconductor devices (and more advanced electronic devices still under development) would never have been possible. Quantum physics is an incredibly complicated realm of science. This chapter is but a brief overview. When scientists of Feynman’s caliber say that “no one understands [it],” you can be sure it is a complex subject. Without a basic understanding of quantum physics, or at least an understanding of the scientific discoveries that led to its formulation, though, it is impossible to understand how and why semiconductor electronic devices function. Most introductory electronics textbooks I’ve read try to explain semiconductors in terms of “classical” physics, resulting in more confusion than comprehension.
Many of us have seen diagrams of atoms that look something like Figure below.
Rutherford atom: negative electrons orbit a small positive nucleus.
Tiny particles of matter called protons and neutrons make up the center of the atom; electrons orbit like planets around a star. The nucleus carries a positive electrical charge, owing to the presence of protons (the neutrons have no electrical charge whatsoever), while the atom’s balancing negative charge resides in the orbiting electrons. The negative electrons are attracted to the positive protons just as planets are gravitationally attracted by the Sun, yet the orbits are stable because of the electrons’ motion. We owe this popular model of the atom to the work of Ernest Rutherford, who around the year 1911 experimentally determined that atoms’ positive charges were concentrated in a tiny, dense core rather than being spread evenly about the diameter as was proposed by an earlier researcher, J.J. Thompson.
Rutherford’s scattering experiment involved bombarding a thin gold foil with positively charged alpha particles as in Figure below. Young graduate students H. Geiger and E. Marsden experienced unexpected results. A few Alpha particles were deflected at large angles. A few Alpha particles were back-scattering, recoiling at nearly 180o. Most of the particles passed through the gold foil undeflected, indicating that the foil was mostly empty space. The fact that a few alpha particles experienced large deflections indicated the presence of a minuscule positively charged nucleus.
Rutherford scattering: a beam of alpha particles is scattered by a thin gold foil.
Although Rutherford’s atomic model accounted for experimental data better than Thompson’s, it still wasn’t perfect. Further attempts at defining atomic structure were undertaken, and these efforts helped pave the way for the bizarre discoveries of quantum physics. Today our understanding of the atom is quite a bit more complex. Nevertheless, despite the revolution of quantum physics and its contribution to our understanding of atomic structure, Rutherford’s solar-system picture of the atom embedded itself in the popular consciousness to such a degree that it persists in some areas of study even when inappropriate.
Consider this short description of electrons in an atom, taken from a popular electronics textbook:
Orbiting negative electrons are therefore attracted toward the positive nucleus, which leads us to the question of why the electrons do not fly into the atom’s nucleus. The answer is that the orbiting electrons remain in their stable orbit because of two equal but opposite forces. The centrifugal outward force exerted on the electrons because of the orbit counteracts the attractive inward force (centripetal) trying to pull the electrons toward the nucleus because of the unlike charges.
In keeping with the Rutherford model, this author casts the electrons as solid chunks of matter engaged in circular orbits, their inward attraction to the oppositely charged nucleus balanced by their motion. The reference to “centrifugal force” is technically incorrect (even for orbiting planets), but is easily forgiven because of its popular acceptance: in reality, there is no such thing as a force pushing any orbiting body away from its center of orbit. It seems that way because a body’s inertia tends to keep it traveling in a straight line, and since an orbit is a constant deviation (acceleration) from straight-line travel, there is constant inertial opposition to whatever force is attracting the body toward the orbit center (centripetal), be it gravity, electrostatic attraction, or even the tension of a mechanical link.
The real problem with this explanation, however, is the idea of electrons traveling in circular orbits in the first place. It is a verifiable fact that accelerating electric charges emit electromagnetic radiation, and this fact was known even in Rutherford’s time. Since orbiting motion is a form of acceleration (the orbiting object in constant acceleration away from normal, straight-line motion), electrons in an orbiting state should be throwing off radiation like mud from a spinning tire. Electrons accelerated around circular paths in particle accelerators called synchrotrons are known to do this, and the result is called synchrotron radiation. If electrons were losing energy in this way, their orbits would eventually decay, resulting in collisions with the positively charged nucleus. Nevertheless, this doesn’t ordinarily happen within atoms. Indeed, electron “orbits” are remarkably stable over a wide range of conditions.
Furthermore, experiments with “excited” atoms demonstrated that electromagnetic energy emitted by an atom only occurs at certain, definite frequencies. Atoms that are “excited” by outside influences such as light are known to absorb that energy and return it as electromagnetic waves of specific frequencies, like a tuning fork that rings at a fixed pitch no matter how it is struck. When the light emitted by an excited atom is divided into its constituent frequencies (colors) by a prism, distinct lines of color appear in the spectrum, the pattern of spectral lines being unique to that element. This phenomenon is commonly used to identify atomic elements, and even measure the proportions of each element in a compound or chemical mixture. According to Rutherford’s solar-system atomic model (regarding electrons as chunks of matter free to orbit at any radius) and the laws of classical physics, excited atoms should return energy over a virtually limitless range of frequencies rather than a select few. In other words, if Rutherford’s model were correct, there would be no “tuning fork” effect, and the light spectrum emitted by any atom would appear as a continuous band of colors rather than as a few distinct lines.
Bohr hydrogen atom (with orbits drawn to scale) only allows electrons to inhabit discrete orbitals. Electrons falling from n=3,4,5, or 6 to n=2 accounts for Balmer series of spectral lines.
A pioneering researcher by the name of Niels Bohr attempted to improve upon Rutherford’s model after studying in Rutherford’s laboratory for several months in 1912. Trying to harmonize the findings of other physicists (most notably, Max Planck and Albert Einstein), Bohr suggested that each electron had a certain, specific amount of energy, and that their orbits were quantized such that each may occupy certain places around the nucleus, as marbles fixed in circular tracks around the nucleus rather than the free-ranging satellites each were formerly imagined to be. (Figure above) In deference to the laws of electromagnetics and accelerating charges, Bohr alluded to these “orbits” as stationary states to escape the implication that they were in motion.
Although Bohr’s ambitious attempt at re-framing the structure of the atom in terms that agreed closer to experimental results was a milestone in physics, it was not complete. His mathematical analysis produced better predictions of experimental events than analyses belonging to previous models, but there were still some unanswered questions about why electrons should behave in such strange ways. The assertion that electrons existed in stationary, quantized states around the nucleus accounted for experimental data better than Rutherford’s model, but he had no idea what would force electrons to manifest those particular states. The answer to that question had to come from another physicist, Louis de Broglie, about a decade later.
De Broglie proposed that electrons, as photons (particles of light) manifested both particle-like and wave-like properties. Building on this proposal, he suggested that an analysis of orbiting electrons from a wave perspective rather than a particle perspective might make more sense of their quantized nature. Indeed, another breakthrough in understanding was reached.
String vibrating at resonant frequency between two fixed points forms standing wave.
The atom according to de Broglie consisted of electrons existing as standing waves, a phenomenon well known to physicists in a variety of forms. As the plucked string of a musical instrument (Figure above) vibrating at a resonant frequency, with “nodes” and “antinodes” at stable positions along its length. De Broglie envisioned electrons around atoms standing as waves bent around a circle as in Figure below.
“Orbiting” electron as standing wave around the nucleus, (a) two cycles per orbit, (b) three cycles per orbit.
Electrons only could exist in certain, definite “orbits” around the nucleus because those were the only distances where the wave ends would match. In any other radius, the wave should destructively interfere with itself and thus cease to exist.
De Broglie’s hypothesis gave both mathematical support and a convenient physical analogy to account for the quantized states of electrons within an atom, but his atomic model was still incomplete. Within a few years, though, physicists Werner Heisenberg and Erwin Schrodinger, working independently of each other, built upon de Broglie’s concept of a matter-wave duality to create more mathematically rigorous models of subatomic particles.
This theoretical advance from de Broglie’s primitive standing wave model to Heisenberg’s matrix and Schrodinger’s differential equation models was given the name quantum mechanics, and it introduced a rather shocking characteristic to the world of subatomic particles: the trait of probability, or uncertainty. According to the new quantum theory, it was impossible to determine the exact position and exact momentum of a particle at the same time. The popular explanation of this “uncertainty principle” was that it was a measurement error (i.e. by attempting to precisely measure the position of an electron, you interfere with its momentum and thus cannot know what it was before the position measurement was taken, and vice versa). The startling implication of quantum mechanics is that particles do not actually have precise positions and momenta, but rather balance the two quantities in a such way that their combined uncertainties never diminish below a certain minimum value.
This form of “uncertainty” relationship exists in areas other than quantum mechanics. As discussed in the “Mixed-Frequency AC Signals” chapter in volume II of this book series, there is a mutually exclusive relationship between the certainty of a waveform’s time-domain data and its frequency-domain data. In simple terms, the more precisely we know its constituent frequency(ies), the less precisely we know its amplitude in time, and vice versa. To quote myself:
A waveform of infinite duration (infinite number of cycles) can be analyzed with absolute precision, but the less cycles available to the computer for analysis, the less precise the analysis. . . The fewer times that a wave cycles, the less certain its frequency is. Taking this concept to its logical extreme, a short pulse—a waveform that doesn’t even complete a cycle—actually has no frequency, but rather acts as an infinite range of frequencies. This principle is common to all wave-based phenomena, not just AC voltages and currents.
In order to precisely determine the amplitude of a varying signal, we must sample it over a very narrow span of time. However, doing this limits our view of the wave’s frequency. Conversely, to determine a wave’s frequency with great precision, we must sample it over many cycles, which means we lose view of its amplitude at any given moment. Thus, we cannot simultaneously know the instantaneous amplitude and the overall frequency of any wave with unlimited precision. Stranger yet, this uncertainty is much more than observer imprecision; it resides in the very nature of the wave. It is not as though it would be possible, given the proper technology, to obtain precise measurements of both instantaneous amplitude and frequency at once. Quite literally, a wave cannot have both a precise, instantaneous amplitude, and a precise frequency at the same time.
The minimum uncertainty of a particle’s position and momentum expressed by Heisenberg and Schrodinger has nothing to do with limitation in measurement; rather it is an intrinsic property of the particle’s matter-wave dual nature. Electrons, therefore, do not really exist in their “orbits” as precisely defined bits of matter, or even as precisely defined waveshapes, but rather as “clouds”—the technical term is wavefunction—of probability distribution, as if each electron were “spread” or “smeared” over a range of positions and momenta.
This radical view of electrons as imprecise clouds at first seems to contradict the original principle of quantized electron states: that electrons exist in discrete, defined “orbits” around atomic nuclei. It was, after all, this discovery that led to the formation of quantum theory to explain it. How odd it seems that a theory developed to explain the discrete behavior of electrons ends up declaring that electrons exist as “clouds” rather than as discrete pieces of matter. However, the quantized behavior of electrons does not depend on electrons having definite position and momentum values, but rather on other properties called quantum numbers. In essence, quantum mechanics dispenses with commonly held notions of absolute position and absolute momentum, and replaces them with absolute notions of a sort having no analogue in common experience.
Even though electrons are known to exist in ethereal, “cloud-like” forms of distributed probability rather than as discrete chunks of matter, those “clouds” have other characteristics that are discrete. Any electron in an atom can be described by four numerical measures (the previously mentioned quantum numbers), called the Principal, Angular Momentum, Magnetic, and Spin numbers. The following is a synopsis of each of these numbers’ meanings:
Principal Quantum Number: Symbolized by the letter n, this number describes the shell that an electron resides in. An electron “shell” is a region of space around an atom’s nucleus that electrons are allowed to exist in, corresponding to the stable “standing wave” patterns of de Broglie and Bohr. Electrons may “leap” from shell to shell, but cannot exist between the shell regions.
The principle quantum number must be a positive integer (a whole number, greater than or equal to 1). In other words, principle quantum number for an electron cannot be 1/2 or -3. These integer values were not arrived at arbitrarily, but rather through experimental evidence of light spectra: the differing frequencies (colors) of light emitted by excited hydrogen atoms follow a sequence mathematically dependent on specific, integer values as illustrated in Figure previous.
Each shell has the capacity to hold multiple electrons. An analogy for electron shells is the concentric rows of seats of an amphitheater. Just as a person seated in an amphitheater must choose a row to sit in (one cannot sit between rows), electrons must “choose” a particular shell to “sit” in. As in amphitheater rows, the outermost shells hold more electrons than the inner shells. Also, electrons tend to seek the lowest available shell, as people in an amphitheater seek the closest seat to the center stage. The higher the shell number, the greater the energy of the electrons in it.
The maximum number of electrons that any shell may hold is described by the equation 2n2, where “n” is the principle quantum number. Thus, the first shell (n=1) can hold 2 electrons; the second shell (n=2) 8 electrons, and the third shell (n=3) 18 electrons. (Figure below)
Principal quantum number n and maximum number of electrons per shell both predicted by 2(n2), and observed. Orbitals not to scale.
Electron shells in an atom were formerly designated by letter rather than by number. The first shell (n=1) was labeled K, the second shell (n=2) L, the third shell (n=3) M, the fourth shell (n=4) N, the fifth shell (n=5) O, the sixth shell (n=6) P, and the seventh shell (n=7) Q.
Angular Momentum Quantum Number: A shell, is composed of subshells. One might be inclined to think of subshells as simple subdivisions of shells, as lanes dividing a road. The subshells are much stranger. Subshells are regions of space where electron “clouds” are allowed to exist, and different subshells actually have different shapes. The first subshell is shaped like a sphere, (Figure below(s) ) which makes sense when visualized as a cloud of electrons surrounding the atomic nucleus in three dimensions. The second subshell, however, resembles a dumbbell, comprised of two “lobes” joined together at a single point near the atom’s center. (Figure below(p) ) The third subshell typically resembles a set of four “lobes” clustered around the atom’s nucleus. These subshell shapes are reminiscent of graphical depictions of radio antenna signal strength, with bulbous lobe-shaped regions extending from the antenna in various directions. (Figure below(d) )
Orbitals: (s) Three fold symmetry. (p) Shown: px, one of three possible orientations (px, py, pz ), about their respective axes. (d) Shown: dx2-y2 similar to dxy, dyz, dxz. Shown: dz2. Possible d-orbital orientations: five.
Valid angular momentum quantum numbers are positive integers like principal quantum numbers, but also include zero. These quantum numbers for electrons are symbolized by the letter l. The number of subshells in a shell is equal to the shell’s principal quantum number. Thus, the first shell (n=1) has one subshell, numbered 0; the second shell (n=2) has two subshells, numbered 0 and 1; the third shell (n=3) has three subshells, numbered 0, 1, and 2.
An older convention for subshell description used letters rather than numbers. In this notation, the first subshell (l=0) was designated s, the second subshell (l=1) designated p, the third subshell (l=2) designated d, and the fourth subshell (l=3) designated f. The letters come from the words sharp, principal (not to be confused with the principal quantum number, n), diffuse, and fundamental. You will still see this notational convention in many periodic tables, used to designate the electron configuration of the atoms’ outermost, or valence, shells. (Figure below)
(a) Bohr representation of Silver atom, (b) Subshell representation of Ag with division of shells into subshells (angular quantum number l). This diagram implies nothing about the actual position of electrons, but represents energy levels.
Magnetic Quantum Number: The magnetic quantum number for an electron classifies which orientation its subshell shape is pointed. The “lobes” for subshells point in multiple directions. These different orientations are called orbitals. For the first subshell (s; l=0), which resembles a sphere pointing in no “direction”, so there is only one orbital. For the second (p; l=1) subshell in each shell, which resembles dumbbells point in three possible directions. Think of three dumbbells intersecting at the origin, each oriented along a different axis in a three-axis coordinate space.
Valid numerical values for this quantum number consist of integers ranging from -l to l, and are symbolized as ml in atomic physics and lz in nuclear physics. To calculate the number of orbitals in any given subshell, double the subshell number and add 1, (2·l + 1). For example, the first subshell (l=0) in any shell contains a single orbital, numbered 0; the second subshell (l=1) in any shell contains three orbitals, numbered -1, 0, and 1; the third subshell (l=2) contains five orbitals, numbered -2, -1, 0, 1, and 2; and so on.
Like principal quantum numbers, the magnetic quantum number arose directly from experimental evidence: The Zeeman effect, the division of spectral lines by exposing an ionized gas to a magnetic field, hence the name “magnetic” quantum number.
Spin Quantum Number: Like the magnetic quantum number, this property of atomic electrons was discovered through experimentation. Close observation of spectral lines revealed that each line was actually a pair of very closely-spaced lines, and this so-called fine structure was hypothesized to result from each electron “spinning” on an axis as if a planet. Electrons with different “spins” would give off slightly different frequencies of light when excited. The name “spin” was assigned to this quantum number. The concept of a spinning electron is now obsolete, being better suited to the (incorrect) view of electrons as discrete chunks of matter rather than as “clouds”; but, the name remains.
Spin quantum numbers are symbolized as ms in atomic physics and sz in nuclear physics. For each orbital in each subshell in each shell, there may be two electrons, one with a spin of +1/2 and the other with a spin of -1/2.
The physicist Wolfgang Pauli developed a principle explaining the ordering of electrons in an atom according to these quantum numbers. His principle, called the Pauli exclusion principle, states that no two electrons in the same atom may occupy the exact same quantum states. That is, each electron in an atom has a unique set of quantum numbers. This limits the number of electrons that may occupy any given orbital, subshell, and shell.
Shown here is the electron arrangement for a hydrogen atom:
With one proton in the nucleus, it takes one electron to electrostatically balance the atom (the proton’s positive electric charge exactly balanced by the electron’s negative electric charge). This one electron resides in the lowest shell (n=1), the first subshell (l=0), in the only orbital (spatial orientation) of that subshell (ml=0), with a spin value of 1/2. A common method of describing this organization is by listing the electrons according to their shells and subshells in a convention called spectroscopic notation. In this notation, the shell number is shown as an integer, the subshell as a letter (s,p,d,f), and the total number of electrons in the subshell (all orbitals, all spins) as a superscript. Thus, hydrogen, with its lone electron residing in the base level, is described as 1s1.
Proceeding to the next atom (in order of atomic number), we have the element helium:
A helium atom has two protons in the nucleus, and this necessitates two electrons to balance the double-positive electric charge. Since two electrons—one with spin=1/2 and the other with spin=-1/2— fit into one orbital, the electron configuration of helium requires no additional subshells or shells to hold the second electron.
However, an atom requiring three or more electrons will require additional subshells to hold all electrons, since only two electrons will fit into the lowest shell (n=1). Consider the next atom in the sequence of increasing atomic numbers, lithium:
An atom of lithium uses a fraction of the L shell’s (n=2) capacity. This shell actually has a total capacity of eight electrons (maximum shell capacity = 2n2 electrons). If we examine the organization of the atom with a completely filled L shell, we will see how all combinations of subshells, orbitals, and spins are occupied by electrons:
Often, when the spectroscopic notation is given for an atom, any shells that are completely filled are omitted, and the unfilled, or the highest-level filled shell, is denoted. For example, the element neon (shown in the previous illustration), which has two completely filled shells, may be spectroscopically described simply as 2p6 rather than 1s22s22p6. Lithium, with its K shell completely filled and a solitary electron in the L shell, may be described simply as 2s1 rather than 1s22s1.
The omission of completely filled, lower-level shells is not just a notational convenience. It also illustrates a basic principle of chemistry: that the chemical behavior of an element is primarily determined by its unfilled shells. Both hydrogen and lithium have a single electron in their outermost shells (1s1 and 2s1, respectively), giving the two elements some similar properties. Both are highly reactive, and reactive in much the same way (bonding to similar elements in similar modes). It matters little that lithium has a completely filled K shell underneath its almost-vacant L shell: the unfilled L shell is the shell that determines its chemical behavior.
Elements having completely filled outer shells are classified as noble, and are distinguished by almost complete non-reactivity with other elements. These elements used to be classified as inert, when it was thought that these were completely unreactive, but are now known to form compounds with other elements under specific conditions.
Since elements with identical electron configurations in their outermost shell(s) exhibit similar chemical properties, Dmitri Mendeleev organized the different elements in a table accordingly. Such a table is known as a periodic table of the elements, and modern tables follow this general form in Figure below.
Periodic table of chemical elements.
Dmitri Mendeleev, a Russian chemist, was the first to develop a periodic table of the elements. Although Mendeleev organized his table according to atomic mass rather than atomic number, and produced a table that was not quite as useful as modern periodic tables, his development stands as an excellent example of scientific proof. Seeing the patterns of periodicity (similar chemical properties according to atomic mass), Mendeleev hypothesized that all elements should fit into this ordered scheme. When he discovered “empty” spots in the table, he followed the logic of the existing order and hypothesized the existence of heretofore undiscovered elements. The subsequent discovery of those elements granted scientific legitimacy to Mendeleev’s hypothesis, furthering future discoveries, and leading to the form of the periodic table we use today.
This is how science should work: hypotheses followed to their logical conclusions, and accepted, modified, or rejected as determined by the agreement of experimental data to those conclusions. Any fool may formulate a hypothesis after-the-fact to explain existing experimental data, and many do. What sets a scientific hypothesis apart from post hoc speculation is the prediction of future experimental data yet uncollected, and the possibility of disproof as a result of that data. To boldly follow a hypothesis to its logical conclusion(s) and dare to predict the results of future experiments is not a dogmatic leap of faith, but rather a public test of that hypothesis, open to challenge from anyone able to produce contradictory data. In other words, scientific hypotheses are always “risky” due to the claim to predict the results of experiments not yet conducted, and are therefore susceptible to disproof if the experiments do not turn out as predicted. Thus, if a hypothesis successfully predicts the results of repeated experiments, its falsehood is disproven.
Quantum mechanics, first as a hypothesis and later as a theory, has proven to be extremely successful in predicting experimental results, hence the high degree of scientific confidence placed in it. Many scientists have reason to believe that it is an incomplete theory, though, as its predictions hold true more at micro physical scales than at macroscopic dimensions, but nevertheless it is a tremendously useful theory in explaining and predicting the interactions of particles and atoms.
As you have already seen in this chapter, quantum physics is essential in describing and predicting many different phenomena. In the next section, we will see its significance in the electrical conductivity of solid substances, including semiconductors. Simply put, nothing in chemistry or solid-state physics makes sense within the popular theoretical framework of electrons existing as discrete chunks of matter, whirling around atomic nuclei like miniature satellites. It is when electrons are viewed as “wavefunctions” existing in definite, discrete states that the regular and periodic behavior of matter can be explained.
Review
• Electrons in atoms exist in “clouds” of distributed probability, not as discrete chunks of matter orbiting the nucleus like tiny satellites, as common illustrations of atoms show.
• Individual electrons around an atomic nucleus seek unique “states,” described by four quantum numbers: the Principal Quantum Number, known as the shell; the Angular Momentum Quantum Number, known as the subshell; the Magnetic Quantum Number, describing the orbital (subshell orientation); and the Spin Quantum Number, or simply spin. These states are quantized, meaning that no “in-between” conditions exist for an electron other than those states that fit into the quantum numbering scheme.
• The Principal Quantum Number (n) describes the basic level or shell that an electron resides in. The larger this number, the greater radius the electron cloud has from the atom’s nucleus, and the greater that electron’s energy. Principal quantum numbers are whole numbers (positive integers).
• The Angular Momentum Quantum Number (l) describes the shape of the electron cloud within a particular shell or level, and is often known as the “subshell.” There are as many subshells (electron cloud shapes) in any given shell as that shell’s principal quantum number. Angular momentum quantum numbers are positive integers beginning at zero and ending at one less than the principal quantum number (n-1).
• The Magnetic Quantum Number (ml) describes which orientation a subshell (electron cloud shape) has. Subshells may assume as many different orientations as 2-times the subshell number (l) plus 1, (2l+1) (E.g. for l=1, ml= -1, 0, 1) and each unique orientation is called an orbital. These numbers are integers ranging from the negative value of the subshell number (l) through 0 to the positive value of the subshell number.
• The Spin Quantum Number (ms) describes another property of an electron, and may be a value of +1/2 or -1/2.
• Pauli’s Exclusion Principle says that no two electrons in an atom may share the exact same set of quantum numbers. Therefore, no more than two electrons may occupy each orbital (spin=1/2 and spin=-1/2), 2l+1 orbitals in every subshell, and n subshells in every shell, and no more.
• Spectroscopic notation is a convention for denoting the electron configuration of an atom. Shells are shown as whole numbers, followed by subshell letters (s,p,d,f), with superscripted numbers totaling the number of electrons residing in each respective subshell.
• An atom’s chemical behavior is solely determined by the electrons in the unfilled shells. Low-level shells that are completely filled have little or no effect on the chemical bonding characteristics of elements.
• Elements with completely filled electron shells are almost entirely unreactive, and are called noble(formerly known as inert). | textbooks/workforce/Electronics_Technology/Book%3A_Electric_Circuits_III_-_Semiconductors_(Kuphaldt)/02%3A_Solid-state_Device_Theory/2.02%3A_Quantum_Physics.txt |
Subsets and Splits