The C.S.I. Syndrome
While increased jury awareness has helped to make evidence handling and investigative practices more accountable, it has also set the bar so high at times that legal professionals despair. Few police departments are equipped with the high-tech gadgets and experts that the television shows have portrayed, and attorneys find themselves at pains to re-educate juries and correct their misperceptions. These crime programs often get things wrong, but audiences generally don't know the difference.
On the shows issues are often oversimplified, drained of ambiguity and the investigation is made to appear quick and easy. The investigators seem always to be correct and the tests conclusive, which makes trial procedure more or less moot. Nothing could be further from the truth. In addition, since the crime dramas are usually solved in a tidy and conclusive manner to satisfy viewers' preference for incontrovertible conclusions, many viewers who become jurors believe that real life crime teams should be able to accomplish what television actors can manage, thinking, "That's how it's done on C.S.I." These shows pay little attention to human factors, and viewers gain the impression that there's ironclad certainty with science, when, in reality, most of these procedures are subject to interpretation. Even scientific experts are prone to disagreement and human error.
Science evolves, and some approaches that once received scientific acceptance fall behind the current standard. For example, an FBI expert claimed in 1995 that the analysis of lead content in bullets proved that a man had murdered his mistress. The accused was convicted and went to prison for life. But in 2005, the FBI discarded this type of analysis as flawed, and two years later the "expert" was revealed as a fraud. The convicted man had spent twelve years in prison based on "science" that wasn't science at all. There was no way for jurors to have made the distinction.
Perhaps the real issue is not so much what jurors believe, but what criminals learn about evidence and investigative techniques. They figure out how to stage crimes, plant evidence, invent a story if they're caught, and even manufacture an illness they don't have. Let's look at one such incident.