The current issue of The Yale Law Journal features an article on the so-called "CSI effect." The conclusion? We really don't know what is going on with jurors and their evaluation of forensic evidence. In fact, it is quite possible that jurors are overvaluing questionable scientific data for the sake of closure in criminal cases.
Entitled "Viewing CSI and the Threshold of Guilt: Managing Truth and Justice in Reality and Fiction," the essay cautions against leaping to conclusions. The fact is, we simply don't know what is going on with jurors.
The article was written by Tom Tyler, a professor at NYU teaching in both the law school and the psychology department. It is a joy to read as it draws broadly from social psychology to help explain what juries do, and why they do it. Even so, the article raises more questions than it answers.
Is the CSI effect real, or is it merely a product of the chattering class of commentators and pundits? Tyler isn't sure. "The CSI effect has become accepted reality by virtue of its repeated invocation by the media. Although no existing emprical research shows that it actually occurs, on a basic level it accords with the intuitions of participants in the trial process," he writes.
Tyler suggests that the CSI effect is far more likely to benefit the state than the defense. Why is that? The desire for justice for the victim is greater than the desire for justice for the defendant. The result is what he refers to as a "reverse CSI effect -- raising the perceived probative value" of scientific data and "increasing the likelihood of conviction."
This is in accord with my sense of trial. Jurors love scientific evidence, even if the prosecutor presents it poorly. I recently tried a case in which DNA evidence played a key role. The prosecutor appeared unaware of what the human genome project was and the analyst on the stand could not rely how the data on which he relied was produced except to say it was generated by computer. Not to worry. Add a sympathetic young rape victim, utter the word "match" and conviction was axiomatic.
Tyler's essay is in the March 2006 edition, Volume 115, Number 5.