The limits of eyewitness testimony

With a wealth of research suggesting that eyewitness identifications can be unreliable, courts and juries should be cautious when they evaluate eyewitness testimony, says APA in its latest amicus briefs.

December 2011, Vol 42, No. 11

Print version: page 26

Limits of eyewitness testimony

Cite This Article

Azar, B. (2011, December 1). The limits of eyewitness testimony. Monitor on Psychology, 42(11). https://www.apa.org/monitor/2011/12/eyewitness

APA has filed two friend-of-the-court briefs supporting the need for courts to carefully scrutinize eyewitness testimony in criminal cases. The cases — one in the U.S. Supreme Court and one in the Pennsylvania Supreme Court — seek rulings that recognize the psychological research findings showing the many circumstances that can lead to eyewitness testimony being flawed and manipulated, says APA's general counsel, Nathalie Gilfoyle, JD.

Although the research clearly points to methods for improving the reliability of eyewitness testimony, there is no national policy guiding how law enforcement agencies gather eyewitness identifications. Historically, researchers have worked to push the Department of Justice and state enforcement agencies to create such a national policy based on the research. And while APA supports such research-based guidelines, there are important battles taking place in the courts, says Gilfoyle.

As the leading association of psychologists in the United States, APA is well-positioned to contribute to judicial understanding of the weight and robust nature of the psychological research on eyewitness testimony, says Gilfoyle. So, at the request of several researchers and the Innocence Project — a national organization of lawyers and public policy experts dedicated to preventing wrongful convictions through reforming the criminal justice system — APA wrote briefs summarizing the research articles that show the limitations of eyewitness identification that have been published since 1977, when the U.S. Supreme Court last considered the issue.

APA filed the first brief Aug. 1 in the Pennsylvania Supreme Court case Commonwealth of PA v. Walker. The case questions the current precedent that Pennsylvania courts will not allow defendants to call expert witnesses to explain the limitations of eyewitness identification or to testify about the nature of human memory. Pennsylvania is one of only a few states that do not allow such testimony, so the goal of the defendant in this case is to bring the state in line with the rest of the country and allow such testimony as part of his defense.

APA's brief explains that juries don't understand the many factors that can influence a witness's ability to accurately identify a suspect, including how much stress a witness is under, whether a weapon is present, the amount of time a witness had to look at the person, the lighting present at the time, how long it's been since someone first witnessed the crime or suggestions of guilt by police.

The power of suggestion is central in Perry v. New Hampshire, the U.S. Supreme Court case for which APA filed a brief on Aug. 5. Perry addresses whether courts, in affording a defendant due process, must review the validity of all eyewitness testimony that was obtained with improperly suggestive tactics. New Hampshire requires such a review only if police or other state officials use improper tactics to obtain eyewitness identification, but not if suggestive tactics occur through happenstance. In Perry, a witness, unsolicited by police, identified the defendant after seeing him through her window standing with the police who were detaining him in handcuffs. Later, the witness was unable to describe him or pick him out of a photo lineup. Still, because the police did not sway her early identification, the court allowed it into evidence.

APA's position is that a defendant should be able to question any suggestive eyewitness identification, using the body of eyewitness research as a guide for what can cause unintentional false accusations, says Gilfoyle.

The proper use of eyewitness testimony is gaining traction, thanks in large part to psychologists' research and testimony. A case in point: On Aug. 24, the New Jersey Supreme Court issued sweeping new rules that make it easier for defendants to challenge eyewitness identification evidence in criminal cases and require judges to hold hearings on the validity of an identification, if there's suspicion that a witness was influenced in any way.

"The New Jersey decision was far and away the most sweeping reform by a court on this issue to date," says Gilfoyle. "The decision is based on testimony by a group of leading researchers in the field of eyewitness identification and reflects a ringing endorsement of the approaches they recommended."

Beth Azar is a writer in Portland, Ore.