It's Evident


The "CSI Effect"—There's No Such Thing as Questions, Just Hidden Answers
Jeff Chesen, Research Attorney

Television crime dramas in recent years have included increasing amounts of forensic science. As a result of this exposure, jurors may be under the mistaken belief that they are educated about forensic science and investigation procedures. They often expect forensic examinations similar to what is depicted on television, including techniques that may not exist in real life. Such jurors may interpret testimony from technologically unsophisticated investigations as the reasonable doubt necessary to acquit a defendant.

The national media began popularizing the concept of the "CSI Effect" with a 2004 USA Today report 1 and further advanced the concept in U.S. News & World Report's cover story, "The CSI Effect, How TV is Driving Jury Verdicts All Across America."2 According to these media reports, CSI is influencing how jurors interpret criminal trials, specifically in their expectation of forensic evidence. Though the argument seemingly makes sense and some anecdotal evidence supports such claims, 3 no published studies have convincingly substantiated the theory.4

Forensic-based television shows have proliferated in the last decade. Shows like CSI (known in syndication as CSI: Las Vegas), CSI: Miami, CSI: New York, Without A Trace, NCIS, Criminal Minds and Numb3rs can be seen on CBS, Bones airs on Fox, and Crossing Jordan is on NBC.5 There are also numerous "true crime" shows on cable channels, including Forensic Files on TruTV (formerly CourtTV), American Justice and Investigative Reports on A&E, and The Secrets of Forensic Science, on TLC. CSI ended the 2004-05 season as the second-highest watched program with an average audience of 26.4 million viewers.6 According to the Nielsen ratings for the 2006-07 primetime season, seven of the top 23 television shows were forensic-based, with CSI finishing fourth and CSI: Miami finishing eleventh.7

An outgrowth of CSI's popularity has been the viewing public's belief that they are "pseudo-forensic experts" themselves. It is from this belief that the CSI Effect has grown: prosecutors, defense attorneys, and judges have all claimed to have witnessed juries who fancy themselves more forensically sophisticated than perhaps the crime scene investigators themselves.

A major problem with the CSI shows is their exaggeration of forensic science's abilities. As a result of the CSI Effect perception, many prosecutors are being trained in the presentation of evidence, particularly forensic evidence. This is because they believe juries demand more thorough forensic science discussions. According to one report, "[a]s more juries watch forensic-based crime programs like CSI on TV, lawyers also find the need to better explain to juries the realities and limitations of forensic evidence."8

The extent to which the so-called CSI Effect could be contributing to an observed increase in acquittals has been examined in several studies. The results so far are mixed, with some even suggesting the shows may make convictions easier to obtain.

In 2004, Michael J. Watkins published the first research on jurors' forensic evidentiary expectations.9 Watkins concluded, "A miseducated citizenry, weaned on media images, may serve to undermine the court process when called upon to serve as jurors."10 The study was statistically flawed in three main ways, including sample size; experience level of the participants consisting of prosecutors and defense attorneys; and the fact that the results were not generalizable across regions.

In 2005 the Maricopa County, AZ, Attorney's Office tried to determine whether the CSI Effect was contaminating the criminal justice system in their jurisdiction.11 Study participants were prosecutors having trial experience with jurors. The prosecutors were asked about their experiences with jurors seeking irrefutable physical and scientific evidence and their perceptions of a possible CSI Effect among juries.12

The Maricopa County report concluded that there is a "significant CSI influence" on its juries 13 and suggested that a disclaimer be used on televisions shows to highlight the fact that CSI is fiction.14 It also reported that county policy will soon direct prosecutors to fully address the techniques used by defense attorneys who employ the CSI Effect to sway juries. This involves countering the CSI Effect through voir dire, opening and closing arguments, and presentation of other evidence and testimony.15

Like the Watkins study, the Maricopa County report has statistical deficiencies. It detailed instances where defendants were acquitted because juries found there was insufficient scientific evidence to convict, yet the report did not consider that scientific evidence is not foolproof. Specifically, there was no control factor for considering that the cases were poor and acquittal inevitable, regardless of whether scientific evidence was presented.

Tyler (Yale Law Journal, 2006) perceived an opposite CSI Effect. He claimed jurors who watch the shows have more of a tendency to convict. He suggested alternative explanations for the observed increase in jury acquittals including jury sympathy for defendants, unrealistic assessments of their cases by prosecutors, and jurors becoming less trusting of legal authorities. He argued that after accounting for these effects, CSI might aid the prosecution; rather than the defense. Tyler theorized that when the desire for a victim’s justice exceeds the desire for the defendant’s justice, jurors may engage in the type of justifications that would lead to a reverse CSI Effect – raising, rather than lowering, the perceived probative value of the evidence and increasing the likelihood of conviction.16

Tyler's theory of the reverse CSI Effect was seemingly supported in a subsequent study by Media Law professor Kimberlianne Podlas.

Podlas' study supported Tyler's findings, concluding that jurors' CSI awareness helps, not hurts, the prosecution. According to this study, frequent CSI viewers were no more influenced by CSI factors in rendering "not guilty" verdicts than were non-frequent viewers. Considering the small minority of CSI viewers who included CSI factors in their verdicts, jurors were not negatively influenced by such factors. Consequently, the study did not support any anti-prosecution CSI Effect.17

The Podlas study also reached the conclusion that there is an opposite, pro-prosecution effect. In some instances, a lower proportion of CSI viewers rendered "not guilty" verdicts relying on CSI reasons. Further, the Podlas study theorized that CSI viewers might be more stringent in assessing evidence, more educated in concepts of proof, or better prepared for jury duty.18