Like three-quarters of the defendants who are cleared by DNA evidence, Cole was convicted based on sincere yet inaccurate eyewitness testimony -- a problem the New Jersey Supreme Court highlighted last week when it revised the state's rules for pretrial hearings and jury instructions based on three decades of research exposing the fallibility of human memory. That decision, together with a case the U.S. Supreme Court will hear this fall, reminds us that the most powerful testimony jurors hear may also be the weakest, subject to hidden influences that can send an innocent man to prison if they remain unexposed.
"Memory does not function like a videotape, accurately and thoroughly capturing and reproducing a person, scene or event," writes Geoffrey Gaulkin, the former judge who prepared a report on the science of eyewitness testimony for the New Jersey Supreme Court. "Memory is, rather, a constructive, dynamic and selective process" that includes three stages: acquisition, retention and retrieval. "At each of those stages," Gaulkin notes, "the information ultimately offered as 'memory' can be distorted, contaminated and even falsely imagined."
Tim Cole's wrongful conviction involved several of the memory-corrupting factors cited by Gaulkin. Cole's accuser, Michele Mallin (who later supported his posthumous exoneration), was held at knifepoint while she was raped, and the presence of a weapon can distract a victim's attention from facial features. High stress also impairs an eyewitness's ability to encode details.
Police claimed that Cole resembled a composite picture they produced based on Mallin's description. "The broad consensus within the scientific community is that composites produce poor results," writes Gaulkin, "because people recognize others holistically, not feature-by-feature in the manner composites are constructed."
Mallin is white, whereas Cole was black, and cross-racial identifications are substantially less reliable than intra-racial identifications. Police presented Mallin with a photo lineup in which Cole's picture stood out because it was the only Polaroid and Cole was the only man looking directly at the camera. The detective who oversaw the lineup was conducting the investigation and may have unconsciously steered Mallin toward Cole, his only suspect.