Eyewitness memory — the ability of witnesses and victims to accurately remember and report criminal events — is one of the most consequential applications of memory research. Eyewitness testimony is compelling to juries but disturbingly fallible: DNA exoneration cases consistently show that eyewitness misidentification is the leading cause of wrongful convictions, contributing to approximately 70% of the 375+ DNA exonerations in the United States as of 2020.
Sources of Error
Eyewitness errors can occur at every stage of the memory process. At encoding, stress, weapon focus (attention drawn to a weapon rather than the perpetrator's face), brief exposure time, poor lighting, and cross-race identification (the own-race bias) all impair initial encoding. During the retention interval, post-event information from media, other witnesses, or leading questions can contaminate the original memory through the misinformation effect. At retrieval, biased lineup procedures, administrator influence, and the pressure to make a choice can produce false identifications.
A critical question for the legal system is whether witness confidence is a reliable indicator of accuracy. Research shows that the relationship is weak, particularly when identification conditions are poor and when confidence is assessed after a delay (during which feedback and post-identification information can inflate confidence). However, initial confidence at the time of identification — before any feedback — shows a stronger relationship with accuracy, leading to recommendations that confidence be assessed immediately at the time of identification.
Lineup Procedures
Research has identified specific procedural factors that affect identification accuracy. Simultaneous lineups (all members presented at once) encourage relative judgment — choosing the member who looks most like the perpetrator relative to others. Sequential lineups (members presented one at a time) encourage absolute judgment — comparing each member to the witness's memory. Double-blind administration (where the administrator does not know which member is the suspect) prevents inadvertent cues. Unbiased instructions (explicitly stating that the perpetrator may not be present) reduce the pressure to choose.
Children as Witnesses
Children present special challenges as witnesses. Younger children are more susceptible to leading questions and social pressure, more likely to make errors of omission (failing to report relevant information) than commission (fabricating information), and may struggle with source monitoring (distinguishing what they saw from what they were told). However, with appropriate interviewing techniques (the cognitive interview, avoiding leading questions, establishing rapport), even young children can provide valuable and reliable testimony.
Reform Recommendations
Based on decades of research, cognitive psychologists have recommended reforms to eyewitness procedures. These include double-blind lineup administration, unbiased instructions, proper filler selection (fillers should match the witness's description, not the suspect), sequential presentation, immediate confidence assessment, and video recording of identification procedures. Many jurisdictions have adopted these recommendations, and research continues to evaluate their effectiveness in reducing false identifications while maintaining correct identifications.