The New Science of Eyewitness Memory | John Wixted | TED

Eyewitness memory, while often perceived as unreliable, is a complex tool that, when understood and utilized correctly, can be crucial for justice. The conventional wisdom for decades has been that eyewitness testimony is inherently unreliable, leading to wrongful convictions. This perception is fueled by cases like Ronald Cotton's, where Jennifer Thompson confidently misidentified him as her attacker, resulting in an 11-year prison sentence before DNA evidence proved his innocence and identified Bobby Poole as the true culprit. Such DNA exoneration cases, numbering in the hundreds, highlight how confident yet mistaken identifications can lead to severe injustices. Scientific research, particularly starting in the 1970s with Elizabeth Loftus, further cemented this view by demonstrating how easily memories can be manipulated and false memories implanted. Studies showed adults could be convinced they had been lost in a shopping mall as children or attacked by vicious animals, even if these events never occurred. These findings suggested that memories are not like video recordings but are more akin to contaminated crime scene evidence, easily distorted. This scientific evidence, combined with wrongful conviction cases, solidified the belief that the legal system should not trust eyewitness memory. However, a new perspective challenges this long-held belief. The issue may not be the inherent unreliability of eyewitness memory due to contamination, but rather how and when a witness's memory is tested. Drawing an analogy to forensic evidence like DNA, which can also be contaminated but is still deemed reliable if collected early and uncontaminated, the same principle applies to memory evidence. Reliable information comes from analyzing uncontaminated evidence. Therefore, eyewitness memory can be highly reliable if tested early in the police investigation, before it becomes contaminated. Scientists now agree that even the first test of a witness's memory for a given suspect can cause contamination. If an innocent suspect's face is shown to a witness who is actively thinking about the crime, even a rejection ("No, that's not the guy") associates the suspect's face with the crime in the witness's memory. This initial association constitutes contamination, and a witness's memory cannot revert to its original state. Therefore, the focus should be on the first, uncontaminated memory test conducted early in the police investigation, not the thoroughly contaminated tests that occur much later at a criminal trial. Unfortunately, courts often do the reverse, prioritizing later, contaminated testimony over the critical initial test. The police typically use a "six-pack photo lineup" to test a witness's memory in a less suggestive way. This involves showing the witness six photos, one of the suspect and five of similar-looking innocent individuals, without revealing who the police suspect. Best practices also include informing the witness that the perpetrator may or may not be in the lineup and having an officer who doesn't know the suspect administer the photos to avoid unintentional influence. When these procedures are followed, it becomes a pure test of memory. Recent scientific findings, published over the last decade, indicate that a confident identification of a suspect from an initial, uncontaminated photo lineup is highly reliable—much more so than previously thought. This challenges the long-standing caution about eyewitness unreliability. These findings prompt a re-examination of DNA exoneration cases. When looking at what witnesses did during their *first* memory test for the person they later confidently misidentified at trial, it's often found they did *not* confidently misidentify the innocent suspect at that initial stage. For example, Jennifer Thompson hesitated significantly during her initial photo lineup, only tentatively identifying Ronald Cotton. Her certainty only developed after significant memory contamination by the time of the trial. Had the initial, inconclusive identification been given proper weight, Ronald Cotton might never have been wrongfully convicted. Even more critically, witnesses often reject the lineup entirely during the first test, stating that none of the individuals match their memory of the perpetrator. This provides clear and reliable evidence of the suspect's innocence when the memory is at its freshest and strongest. Yet, many witnesses who initially reject a lineup will, after memory contamination, confidently identify the very same person at trial, often without recalling their initial rejection. These defendants are frequently convicted without DNA evidence to prove their innocence. The new understanding of memory science can help exonerate such individuals. The case of Miguel Solorio, arrested for murder in 1998, exemplifies this. Four witnesses rejected his photo lineup initially, but two identified him at trial over a year later, leading to his conviction and 25 years in prison. He was finally exonerated in late 2023 with the help of this new science, which highlighted the importance of the first uncontaminated test. Similarly, Charles Don Flores, on death row since 1998, was identified by a witness who initially described a very different perpetrator and rejected a lineup containing Flores's photo. The jury never heard about the witness's initial, uncontaminated memory. The reforms needed are clear: prioritize the first test of a witness's uncontaminated memory in police investigations and legal proceedings, de-emphasize confident identifications made after an earlier rejection of the same face (as this suggests contamination), and educate legal professionals about this new science. While this message initially alarms both defense attorneys (who fear any reliance on eyewitness memory) and prosecutors (who fear letting the guilty go free by disregarding later identifications), it simply reflects how memory works. By following this science, society can better serve justice, preventing wrongful convictions and exonerating the innocent.