Eyewitnesses Research

Source: The Futurist, Dec 1998 v32 i9 p14(2).

Title: Witnesses: a weak link in the judicial system.(testimoniesduring criminal trials)
Author: Dan Johnson

Abstract: The American Psychological Assn has found evidence that eyewitness testimonies are not reliable sources of information during criminal trials.
Studies reveal that eyewitness get influenced by the feedback given by the police after a suspect is identified.

Subjects: Witnesses - Research
Criminal procedure - Research
Organizations: American Psychological Association - Research

Electronic Collection: A53368729 RN: A53368729

Full Text COPYRIGHT 1998 World Future Society

Witness problems can hinder criminal trials and science cases.
Jurors in criminal trials are more often persuaded by the testimony of confident eyewitnesses than by objective evidence, such as fingerprints, fibre analyses, or DNA matches.
But eyewitness testimony can be seriously flawed because eyewitnesses are influenced by the positive and negative responses they receive from the police after they identify a suspect, according to two recent studies by the American Psychological Association.

In the first study, 352 people were shown a grainy surveillance videotape of a person who later shot and killed a store security guard. The participants were asked to identify the man they had seen on the videotape by choosing from a photospread of five faces that did not include the actual gunman. After picking a suspect, the participants were randomly told that they had made either the correct or the incorrect choice, or received no feedback. They then answered a series of questions, including how easy or hard it was to choose a photo, how good a view they had of the gunman, and how willing they would be to testify in court.

Although all of the participants were equally wrong, those who received positive feedback were the most confident of their decisions. Positive feedback also seemed to distort the witnesses' reports of almost
every
Aspect of the identification process. These participants remembered having a better view of the culprit, needing less time to make the identification, paying more attention to the videotape, and having an easier time choosing the suspect than participants who received negative feedback or no feedback.

The memory distortion resulting from positive feedback served "to manufacture credible witnesses from a pool of inaccurate witnesses who were not particularly credible on their own," say the authors of the study. The second study confirmed that most of the eyewitnesses' memories were influenced by positive feedback, even though they denied the influence.

Police practices should be changed in light of the study results, according to the American Psychological Association.
The police can counter feedback-caused memory distortion by asking witnesses how confident they are about their identifications before receiving any feedback. The study authors also advocate that police lineups and photospreads should be supervised by officers who do not know the suspect's identity.

Overreliance on Experts

Litigation that involves complicated scientific matters poses a different kind of witness problem: a battle between teams of expert witnesses presenting complex scientific arguments that can overwhelm judges and juries.

Expert witnesses are often called to testify in cases in which plaintiffs claim that toxic substances have caused injury or disease. These proceedings have involved asbestos, breast implants, the Dalkon Shield, lead, and tobacco. In the past, such cases were usually tried after a credible body of scientific evidence had been amassed. Toxic cases are now harder to adjudicate because plaintiffs' lawyers can make more money if they file suit quickly, before hundreds of similar cases develop, writes Richard Monastersky in Science
News.

"In most cases, judges and juries have little or no scientific training or background, so you're presenting them with very complicated matters in a style that is not conducive to learning scientific matters," says Deborah Runkle of the American Association for the Advancement of Science. One solution is to streamline the process of finding neutral experts who can help a judge assess the testimony of the opposing parties' expert witnesses during pretrial proceedings.

But even independent experts can wield enormous influence over the judicial system. In a Federal Judicial Center investigation of cases involving scientific issues, 56 of 58 judges' verdicts matched the guidance given to them by court-appointed experts. Critics argue that, not only are experts without conflict of interest hard to find, but their clear influence over the outcomes of cases usurps the roles of advocates, judges, and juries in the trial system. - Dan Johnson

Sources: American Psychological Association, Public Affairs Office, 750 First Street, N.E., Washington, D.C. 20002. Telephone [phone]; Web site www.apa.org. "Courting Reliable Science" by Richard Monastersky, Science News (April 1998),
1719 N Street, N.W., Washington, D.C. 20036. Telephone [phone]; e-mail [e-mail].