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Winter 2014 Vol. 14 Number 2

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Mistaken Identification

Improving the Accuracy of Eyewitness IDs in Criminal Cases

In 1984, college student Jennifer Thompson was raped in her apartment in Burlington, North Carolina. Based on a composite sketch of the rapist created with Thompson's help, the police picked up a local man named Ronald Cotton. Thompson was shown six photos, from which she chose two. One was of Cotton. "I think this is the guy," she said, pointing to Cotton. "You're sure?" the lead detective asked, and she responded, "Positive." Thompson asked, "Did I do ok?" The detectives responded, "You did great." She then was shown a live lineup, in which Cotton was the only person repeated from the prior photo array, a fact that would make him more familiar and may suggest he was the prime suspect. After hesitating between him and another man, Thompson told the police that Cotton "looks the most like him." Again, the detectives reinforced her decision, telling her it was the same person she picked from the photos.

At Cotton's trial, Thompson said she was "absolutely sure" he was the rapist, and Cotton was sentenced to life in prison. But after he had served 10 and a half years, DNA tests exonerated him, instead implicating Bobby Poole -- a man who had been presented to Thompson at a post-trial hearing, but whom Thompson did not recognize. Cotton and Thompson have since written a book together describing the case and their experiences.

This story illustrates some of the pitfalls in eyewitness identification, along with the tragic cost of errors. It is not an isolated case; nearly three-quarters of DNA exonerations since 1989 involved at least one mistaken eyewitness. What causes these mistakes? Science in the past two decades has revealed much about the factors that can lead to mistaken identifications. This research is reviewed in a recent National Research Council report, which recommends best practices that law enforcement and courts should follow to improve the likelihood of accurate identifications.

Conditions during a crime such as dim lighting or stress can influence a person's visual perceptions, as can the presence of a distracting element like a knife or gun, the report says. Gaps in sensory input are filled by expectations based on an individual's prior experiences with the world. And our memories are not stable and reliable, like snapshots in a photo album. Instead, they are continuously evolving; as memories are processed, encoded, stored, and retrieved, many factors -- such as a story in a newspaper or a comment made by a police officer -- can compromise their fidelity to actual events.

Given these inherent limitations, caution should be exercised when handling eyewitness identifications and relying on them in court, the report says. Police departments should use "double-blind" processes in which the administrator of a lineup or photo array does not know which person is the suspect -- a step that will keep the administrator from unintentionally cueing the witness. Eyewitnesses should also be given standardized instructions. They should be told that the suspect may or may not be in the lineup, for example, and that the investigation will continue regardless of whether an identification is made. Witness's confidence levels at the time of the initial identification should be recorded verbatim, and lineup administrators should not offer feedback.

The report also recommends best practices for judges, who have an obligation to ensure the reliability of evidence presented at a trial. Judges should conduct a pre-trial inquiry about any eyewitness identifications -- for example, about the procedures followed by law enforcement -- to aid decisions about whether an identification is admissible. Judges also should use expert testimony or jury instructions to inform jurors about factors that could influence the accuracy of a particular identification.

Because more needs to be known about some aspects of eyewitness identification, a National Research Initiative on Eyewitness Identification should be established, the report adds.

-- Sara Frueh

Identifying the Culprit: Assessing Eyewitness Identification. Committee on Scientific Approaches to Understanding and Maximizing the Validity and Reliability of Eyewitness Identification in Law Enforcement and the Courts; Committee on Science, Technology, and Law, Division on Policy and Global Affairs, and Committee on Law and Justice, Division of Behavioral and Social Sciences and Education (2014, approx. 160 pp.; ISBN 978-0-309-31059-8; available from National Academies Press, tel. 1-800-624-6242; $44.95 plus $5.00 shipping for single copies).

The committee was co-chaired by Thomas Albright, professor and director, Vision Center Laboratory, and Conrad T. Prebys Chair in Vision Research, Salk Institute for Biological Studies; and Jed Rakoff, senior judge, United States District Court for the Southern District of New York. The study was sponsored by the Laura and John Arnold Foundation.

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