Excerpted from Pinpoint by Greg Milner.

Ralph and Robert Schwitzgebel were identical twins from Ohio, champion high school debaters who won the state title in 1951, graduated from different colleges, and both — unbeknownst to the other — applied to Harvard’s graduate program in psychology. “We kind of show up on campus one day — ‘What are you doing here?’ ” Robert recalls. It was a heady time at the Harvard psych department. The faculty included B. F. Skinner, behaviorism’s leading figure, and also Timothy Leary, who demonstrated during his brief time at the university that he was willing to go to unprecedented lengths to test the molding of human behavior. Leary became Ralph’s adviser. Ralph coauthored the paper detailing Leary’s infamous Concord Prison experiment, in which young inmates were given psilocybin as part of group therapy, between 1961 and 1963. The study proposed that the drug had a positive effect on the recidi- vism rate of the experimental group.

Ralph took from his mentor a willingness — even an eagerness — to deploy unorthodox methodologies, especially in the treatment of young people on the margins of society. Ralph wanted to merge the experimental psychologist’s lab with the psychotherapist’s office. In 1959, he founded the Science Committee on Psychological Experimentation (SCOPE), using grant money to counsel gang members and other at-risk youth in the Cambridge, Massachusetts, area. He believed that the therapy methods traditionally used with juvenile delinquents seldom worked because of a culture clash between “delinquent” and “nondelinquent” cultures. Accordingly, he did not consider these people his patients so much as his employees. He would approach them on street corners and offer them money and equipment to film their lives, keep audio diaries, and submit to interviews. Over time, he would win their trust, and their behavior would begin to change. It was a form of stealth therapy.

SCOPE’s work was controversial. Some psychologists criticized Ralph for advocating a “soft” approach that coddled the kids, failed to address the root causes of their delinquency, and had no long-term positive effect on their personalities. Ralph countered that he was taking a practical approach. He wanted to affect behavior in a way that reduced the likelihood that the kids would commit crimes and get themselves into trouble right now. Considered decades later, much of SCOPE’s work seems ahead of its time — especially the emphasis on employing recording media for self-expression — while some of it now seems glaringly retrograde. In a New York Times profile of Ralph five years after SCOPE was founded, he cited, as evidence of the efficacy of his behavior modification methods, a youth who came to SCOPE for help with “homosexual tendencies.” His treatment regimen involved drinking ipecac when the urges grew strong, and he was now married and “very content,” Ralph said.

In Streetcorner Research, a book Ralph published in 1964 that detailed his work, he asserted that the “nondelinquent” culture seldom interfaced with the “delinquent” one in a way that contained enough “intensity” to break through and elicit behavioral change. An alternative approach would be to develop “a humane technology which will eliminate unwanted behaviors and develop in their place desirable behaviors.” He was talking about positive reinforcement, a key tenet of Skinner’s approach to behaviorism. Skinner was Robert’s advisor. Robert was on board with SCOPE’s project, and became his brother’s chief collaborator.

The Schwitzgebels disdained pigeons, Skinner’s experimental animal of choice. “Pigeon data was really boring, but the reinforcement idea seemed really powerful,” Robert says. “Certainly juvenile delinquents and gang members were a lot more interesting than pigeons, so let’s just go out and get some, hook them up, and use reinforcement. They don’t cost much more than pigeons, they’re more interesting, and they can be very cooperative. So that’s what we did.”

The freeform atmosphere in the department favored this kind of convention-flouting. “No forms, no institutional review committees — we didn’t have to do any of that,” Robert says, laughing. “This was the days of the sixties and Leary.”

Ralph had an epiphany while seeing the movie West Side Story. What if there had been some communications system that could detect when the gang was about to fight, putting them in touch with people who could talk them down? Ralph envisioned a small transmitter, worn on the body, that could detect certain forms of behavior and transmit data to a base station for analysis. The station could send back signals in a sort of “behavioral feed- back system that may have considerable therapeutic potential.” Although that idea never came to fruition, the brothers managed to construct a different kind of monitoring system.

At a cocktail party, Ralph met an engineer, and the two got to talking about Ralph’s West Side Story idea. The engineer was intrigued. He happened to have a line on some surplus military missile tracking equipment, which he helped the brothers set up in a former car showroom they rented. With this, they built the world’s first functioning electronic monitoring system. Over an area of a few square blocks, the brothers erected transponders, on places like the tops of telephone poles and behind the cross on the roof of the Cambridge Baptist Church. The beacons detected the presence of anyone wearing a receiver contained in a two-pound box, worn on a leather belt. The person’s location, updated every thirty seconds, would show up as a light on an electronic wall map at the office.

To recruit subjects, they’d strike up conversations with rough-looking teens on Cambridge street corners, saying they were doing research on what kids thought of police. Those who seemed interested were invited back to the Schwitzgebels’ office the next day to record some of their thoughts. The positive reinforcement would start immediately, before the kids were fully informed about the project. A kid who showed up early might receive a $15 bonus. Throwing away an empty soda can at the office might elicit praise from the brothers, who would inform the kid that because of his spontaneous good behavior he was receiving two free pizzas. The awards appeared to the subjects as random — they never knew when one was coming or what it might be, a central tenet of Skinnerian positive reinforcement. “It absolutely has to be a variable interval, so you don’t know when it will happen, and a variable ratio, so you don’t know how much work you have to put in,” Robert explains. “It’s like a junior Las Vegas. If you knew how much you would win or lose, you might not go to Vegas.”

Once a subject had proven to be dependable and fit the criteria — a troublemaker, someone clearly headed down the wrong path, but without a criminal record — the brothers would let them in on the full project. A kid would be asked if he would be willing to wear a leather belt attached to a two-pound box containing a receiver, as well as an antenna and rechargeable batteries.

The point of the experiment was to watch over kids who had already proven that they could not — or would not — obey society’s strictures. It would be more like a way of knowing if these youth were where they were supposed to be at any given time. If they were at school, or work, or home, or even church, that meant they were not only living their lives according to the rules, but also not placing themselves in areas where trouble was likely to find them. If the system showed that the kid was where he was supposed to be, he might receive a reward, but he would never be penalized for being in the wrong place. “Our idea was no punishment,” Robert says. “That was Skinner’s rule — no punishment, just reinforce them when they were at school or drug treatment or whatever.”

From the beginning, the brothers thought of their experiment in grand terms, imagining an enhanced version of their system for parolees. Maybe the belt could somehow record physical and physiological variables, such as nervous gestures and anxiety, or even an increased blood alcohol level, sending an alert if data suggested that the wearer was in a state to do something rash. If the crime involved the use of a motorcycle, perhaps the device could measure the speed the wearer was traveling. Tones could be used as codes. Monitored people who showed up at work might receive a “good job” tone; staying out late might elicit a “return home” tone. The Schwitzgebels never saw their approach as purely a matter of surveillance, but rather an efficient and effective method of positive reinforcement that would reduce recidivism, since parolees would know there was always a record of their behavior. They envisioned the day when prisons were obsolete, and became “museums or monuments to the inhumanity and ineffectiveness of social retribution.”

Although these plans never solidified, the Schwitzgebels continued to run their program for wayward youth, and were pleased with the results. They established a small nonprofit with money they received for selling the rights to their story to Universal Studios. (A movie was never made.) The program finally folded in 1975. The brothers had failed to persuade many people that electronic surveillance and positive reinforcement were a winning criminal justice combination. To critics on the right, “positive reinforcement” smacked of coddling criminals. To those on the left, it seemed ludicrously Orwellian. In Kind and Usual Punishment, Jessica Mitford’s 1973 book about the problems with the American prison system, she took Ralph to task for his advocacy of electronic monitoring: “Is there also a broad hint for the rest of us concealed in here somewhere? For if the ‘behaviors in the community’ can be electronically spotted and corrected for parolees, why not for the entire population?”

“My brother got a really hostile letter from the editor of Probation magazine, saying this is really Big Brother stuff,” Robert says. “It said the next thing that would happen was it would be implanted, and the devices would be ‘Big Mother’ or something of that sort.” The brothers both moved into academia. With their ideas of electronic monitoring seeming fanciful or fascist, depending on the critic, the Schwitzgebels’ dream of better living through tracking appeared to be over. It would, in fact, be resurrected, in a form the brothers hardly recognized.

At the same time the Schwitzgebels were laying the conceptual and (to a lesser degree) technological groundwork for electronic monitoring of offenders, the criminal justice system was discovering the legal ramifications. In the U.S., this involved debates over the Fourth Amendment’s guarantee against illegal searches and seizures — and how this edict dovetailed with the concept of privacy in the context of new technologies.

The first important test case, Katz v. United States, reached the U.S. Supreme Court in 1967. FBI agents had placed an electronic listening device in a phone booth they knew their target used to call in illegal gambling wagers. The court ruled that this practice violated the man’s Fourth Amendment rights, because although the phone booth was public space, its usage implied a reasonable expectation of privacy. The decision established the idea that Fourth Amendment protections did not begin and end with one’s home or private property, but also extended to spaces one occupies temporarily.

Throughout the 1970s, police departments began to deploy pre-GPS surveillance setups called beepers, which used a receiving antenna and a radio frequency detector to follow the signal emitted by a surreptitiously placed transmitter. Police would manually adjust the antenna in search of the signal, like pre-cable television viewers manipulating the rabbit-ear antenna attached to their sets. Sometimes police in a car would hang an antenna off of each side to see which one got the stronger signal. The cleanness of the signal pointed to the suspect’s direction, while a signal-strength meter gave an indication of distance. Some officers claimed their ears were better than the meters and “trained” themselves to hear the difference. The range was as small as two blocks in a congested area, two to four miles on an open road, and about 20 miles if the beeper was in a heli- copter or otherwise airborne. As there was no map component, the beeper setup amounted to a crude form of dead reckoning, imparting a rough sense of where the transmitter was in relation to the receiver’s location.

Using a beeper to track a suspect was the conceptual converse of putting a bugging device in a phone booth. The latter was all about enhancing observation of a single space, waiting for a suspect to move into it. A beeper involved observing a device in the possession of a person, tracking the suspect’s mobility.

In 1983, the Supreme Court heard United States v. Knotts, a case that turned on whether this was a meaningful distinction. Employees of 3M in St. Paul, Minnesota, suspected that a former coworker had stolen chemicals used to produce methamphetamine. Based on their tip, police trailed the man and witnessed him buying similar chemicals from another company. That company agreed to let police install a beeper in a container of chloroform to be sold to the suspect. The sale went as planned, the man loaded the materials into his car and drove away, with police following the beeper signal to the home of another man, who received the chloroform and transferred it to his car. Police continued to follow this car as it crossed the state line into Wisconsin. Then they lost the signal.

An hour later, a police helicopter picked it up again. The signal suggested that the package was no longer in motion, and it was traced to a rural cabin. Observing the cabin, the police saw the suspect move the chemicals outside of it. Swiftly obtaining a warrant, they searched the cabin, discovering extensive lab equipment and 14 pounds of pure amphetamine. They made arrests, and won convictions that broke up a drug ring.

The police had fulfilled their Fourth Amendment obligations (or so they assumed) by getting a warrant to search the premises. After all, their surveillance had yielded a plethora of probable cause. But what about the tool that had furthered this surveillance — the beeper? A lawyer for one of the defendants reasoned that using the beeper was itself a search, requiring a separate warrant. The argument didn’t fly. The Supreme Court unanimously upheld the conviction, on the grounds that the privacy one could reasonably expect inside a domicile — the cabin — did not extend to the public roads that led the police to it. Following someone on that public space did not constitute a search, even if the beeper made that search easier and more comprehensive. “Nothing in the Fourth Amendment prohibited the police from augmenting their sensory faculties with such enhancement as science and technology offered them in this case,” Justice William Rehnquist wrote.

Knotts was a line in the sand — or, more accurately, the distinct absence of one, washed away by the high tide of technological progress. Regardless of how greatly technology magnifies our senses, noting the movement of a person through the world did not amount to a search of that person, or that person’s possessions. When you were in public, you were subject to the public’s gaze.

A year later, the Supreme Court decided a similar case, United States v. Karo, and decided that there really was a line. With his consent, federal agents installed a beeper in a can of ether belonging to a government informant, who then sold the ether to people who used it to extract smuggled cocaine. Although the court rejected the idea that the tracking itself required a warrant — since the can belonged to the agents when they installed the beeper, there was no privacy violation — the justices had a problem with how the tracking had proceeded.

The Knotts police had let the beeper lead them to the cabin, but they glimpsed the movement of the telltale chemicals outside the cabin with their naked eyes. The federal agents in Karo allowed the beeper to do more of the work for them. Rather than staying on the suspect’s trail and then seeing what they could see, they simply traced the beeper’s signal to a house in Taos, New Mexico. From this, they could confidently assume that the ether was inside. Technology had given them rudimentary x-ray vision that allowed them to look through the walls of the house to “see” the illegal activity inside. Although monitoring a beeper is “less intrusive than a full-scale search,” Justice Byron White wrote, this beeper had revealed “a critical fact about the interior of the premises that the Government is extremely interested in knowing and that it could not otherwise have obtained without a warrant.” The use of the beeper in this case, the court decided, constituted an unlawful search.

It was just a few years since the launch of the first GPS satellite. As the constellation grew — and, along with it, a method of tracking that further enhanced the ability of humans to observe and gather data — the question of sensory augmentation and the law would grow more urgent.

Excerpted from PINPOINT: How GPS is Changing Technology, Culture, and Our Minds. Copyright © 2016 by Greg Milner. Published by W.W. Norton & Company.

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