accredited laboratories make mistakes. Furthermore, accreditation is a voluntary program, except in a few jurisdictions in which it is required (New York, Oklahoma, and Texas)36 (see Chapter 7).

The “CSI Effect”

Media attention has focused recently on what is being called the “CSI Effect,” named for popular television shows (such as Crime Scene Investigation) that are focused on police forensic evidence investigation.37 The fictional characters in these dramas often present an unrealistic portrayal of the daily operations of crime scene investigators and crime laboratories (including their instrumentation, analytical technologies, and capabilities). Cases are solved in an hour, highly technical analyses are accomplished in minutes, and laboratory and instrumental capabilities are often exaggerated, misrepresented, or entirely fabricated. In courtroom scenes, forensic examiners state their findings or a match (between evidence and suspect) with unfailing certainty, often demonstrating the technique used to make the determination. The dramas suggest that convictions are quick and no mistakes are made.

The CSI Effect specifically refers to the real-life consequences of exposure to Hollywood’s version of law and order. Jurists and crime laboratory directors anecdotally report that jurors have come to expect the presentation of forensic evidence in every case, and they expect it to be conclusive. A recent study by Schweitzer and Saks found that compared to those who do not watch CSI, CSI viewers were “more critical of the forensic evidence presented at the trial, finding it less believable. Forensic science viewers expressed more confidence in their verdicts than did nonviewers.”38 Prosecutors and defense attorneys have reported jurors second guessing them in the courtroom, citing “reasonable doubt” and refusing to convict because they believed that other evidence was available and not adequately examined.39

Schweitzer and Saks found that the CSI Effect is changing the manner in which forensic evidence is presented in court, with some prosecutors believing they must make their presentation as visually interesting and appealing as such presentations appear to be on television. Some are concerned that the conclusiveness and finality of the manner in which forensic evidence is


National Institute of Justice. 2006. Status and Needs of Forensic Science Service Providers: A Report to Congress. Available at


See U.S. News & World Report. 2005. The CSI effect: How TV is driving jury verdicts all across America. April 25.


N.J. Schweitzer and M.J. Saks. 2007. The CSI Effect: Popular fiction about forensic science affects public expectations about real forensic science. Jurimetrics 47:357.


See U.S. News & World Report, op. cit.

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