Essex, Md., resident Kirk Bloodsworth served nine years in prison for the rape and murder of a 9-year-old girl before a 1993 DNA test proved his innocence. He's one of nearly 200 people in the United States set free since the introduction of forensic DNA testing in 1989, according to The Innocence Project, a New York-based nonprofit dedicated to exonerating the wrongfully convicted. In Bloodsworth's case, as in nearly three-quarters of DNA exonerations,a mistaken eyewitness identification led to a wrongful conviction.
That's because jurors misunderstand how memory works, say experts. In fact, more than half of jurors don't understand how variables such as lighting, viewing distance or even how a law-enforcement agency conducted its lineup might affect the accuracy of eyewitness testimony, according to a study in the winter 2006 issue of Jurimetrics (Vol. 46, No. 2, 177-214). The study tested approximately 1,000 Washington, D.C.-area potential jurors on their understanding of eyewitness reliability.
Finding a way to change that statistic can be tough, says Steven Clark, PhD, a psychology professor at the University of California-Riverside. Past efforts have focused on educating jurors directly through expert witnesses, or by spreading the word through media appearances. However, psychologists are increasingly taking a different tack: Educating judges, who have the power to accept or deny expert eyewitness testimony, provide jury instructions and determine how a court case is run.
"The judge is a gatekeeper as to what gets to juries," says Elizabeth F. Loftus, PhD, professor of psychology and social behavior at the University of California-Irvine, and a well-known memory researcher. "That's why judicial education is so important."
The jury junket
After more than 30 years of research, psychologists have identified many variables affecting eyewitness identification. Factors like lighting, race, presence of a weapon and a witness's degree of trauma while seeing the perpetrator all may reduce the accuracy of identifications.
To educate juries about the pitfalls of memory, attorneys call on psychologists to present their research as expert witnesses, often during trials where eyewitness identification is the sole or primary evidence against the defendant, says Gary Wells, PhD, a psychology professor at Iowa State University who, with Loftus and Clark, serves as one of about 50 well-known eyewitness experts in the U.S. But expert testimony can be expensive for attorneys and time-intensive for psychologists, who spend hours learning about the intricacies of a case and preparing their testimony. In the end, says Wells, the testimony affects only one case and one jury at a time.
That is, if the judge even allows the expert to present their research, Wells says. Many judges argue that eyewitness information is within a juror's "realm of common knowledge."
"Probably half of the judges in this country or more would generally be inclined to not permit expert testimony on eyewitness issues," says Wells. That's often because judges believe that the testimony will overpower an eyewitness's argument, says Wells. But based on tests with simulated juries, he says, expert testimony tends to cause jurors to merely pay closer attention to the conditions and potential biases of the eyewitness evidence.
"It's not an overwhelming effect, which is good," says Wells.
In addition to being inefficient and costly, experts agree that providing testimony and suffering through adversarial cross-examinations is not exactly enjoyable.
"It's not the way, in the long run, to tackle this problem," says Wells.
Educating the gatekeepers
True or false? At trial, an eyewitness's confidence is a good predictor of his or her accuracy in identifying the defendant as the perpetrator of the crime. If you answered false, you're doing better than nearly 70 percent of judges in a recent survey. The study, in the May 2004 Applied Cognitive Psychology (Vol. 18, No. 4, 427-443), showed that judges correctly answered only 55 percent of the survey's 14 questions about eyewitness testimony and the factors that contribute to its reliability. Despite their legal and judicial experience, even judges seem confused about what factors affect identification accuracy, says Richard Wise, JD, PhD, an assistant psychology professor at the University of North Dakota and the lead author of the study.
"The type of legal and judicial training and experience that judges have is not very helpful for them in understanding eyewitness testimony," says Wise. To combat this, psychologists are increasingly spending time educating judges. Both Wells and Loftus have presented lectures to groups of judges, and believe this approach shows promise for more wide-ranging effects.
"It puts more expertise in the courtroom without having to have an expert," says Wells.
Wise, a former prosecutor, is developing a course for judges with the help of Martin A. Safer, PhD, a psychology professor at the Catholic University of America in Washington, D.C., that they hope to incorporate into judicial colleges. This will help newly appointed judges learn about eyewitness testimony's unreliability before their first case. The course, Wise says, will provide judges with an overview of the problem, explain why eyewitnesses make errors and recommend ways for judges to ensure jurors receive information they need.
Judge and jury education, however, is only part of the solution, says Wells. Going to the source of the problem-improving how police conduct eyewitness interviews and identification procedures-may hold the best chances for reducing false convictions, he says. Wells, for example, helped develop a National Institute of Justice guide for law enforcement on eyewitness evidence, which outlines basic procedures for obtaining reliable and accurate information from eyewitnesses and running identification procedures. The guide recommends things like avoiding leading or suggestive questions about the crime during interviews with the witness, and instructing the witness that the perpetrator may or may not be present during lineup procedures. These types of initiatives, he says, help prevent witness biases from occurring in the first place.
In the end, say experts, education at all levels of the judicial system-jurors, judges, police officers, even attorneys-will keep people like Bloodsworth from spending years in prison for a crime they did not commit.
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