analysis of skid marks can frequently allow a reconstruction of the accident. By measuring the length of such marks and using dynamic analysis of the car and road conditions at the time of the accident, it may be found that a driver underestimated his or her speed. Circumstantial evidence is also prevalent in attempts to recover damages from alleged tortfeasors. Criminal law Circumstantial evidence is used in criminal courts to establish guilt or innocence through reasoning. With obvious exceptions (immature, incompetent, or mentally ill individuals), most criminals try to avoid generating direct evidence. Hence, the prosecution usually must resort to circumstantial evidence to prove the existence of mens rea, or intent. One example of circumstantial evidence is the behavior of a person around the time of an alleged offense. In the case of someone charged with theft of money, were the suspect seen in a shopping spree purchasing expensive items shortly after the time of the alleged theft, the spree might prove to be circumstantial evidence of the individual's guilt. Forensic evidence Other examples of circumstantial evidence are fingerprint analysis, blood analysis or DNA analysis of the evidence found at the scene of a crime. These types of evidence may strongly point to a certain conclusion when taken into consideration with other facts—but if not directly witnessed by someone when the crime was committed, they are still considered circumstantial. However, when proved by expert witnesses, they are usually sufficient to decide a case, especially in the absence of any direct evidence. Owing to subsequent developments in forensic methods, old undecided cases (or cold cases) are frequently resolved. Validity of circumstantial evidence A popular misconception is that circumstantial evidence is less valid or less important than direct evidence, which is popularly assumed to be the most powerful, but this is not the case. Many successful criminal prosecutions rely largely or entirely on circumstantial evidence, and civil charges are frequently based on circumstantial or indirect evidence. Indeed, the common metaphor for the strongest possible evidence in any case—the "smoking gun"—is an example of proof based on circumstantial evidence. Similarly, fingerprint evidence, videotapes, sound recordings, photographs, and many other examples of physical evidence that support the drawing of an inference, i.e., circumstantial evidence, are considered very strong possible evidence. In practice, circumstantial evidence can have an advantage over direct evidence in that it can come from multiple sources that check and reinforce each