Post-Identification Feedback Effect

The post-identification feedback effect is a finding in eyewitness identification research in which telling a witness that they identified the right suspect from a lineup, even when that feedback is false or given purely for research purposes, inflates the witness's later, retrospective reports of how confident they had been at the time, how good a view of the culprit they had, how much attention they paid, and how quickly and easily the identification came to them, distorting the witness's own memory of the identification experience itself rather than only their current stated confidence. The psychologists Gary Wells and Amy Bradfield demonstrated the effect in a study published in 1998, in which participants who had actually misidentified an innocent person from a lineup, and then received confirming feedback that they had picked correctly, went on to rate their identification experience far more favorably in hindsight than participants who received no such feedback, even though the underlying identification was wrong in both groups. The finding has been particularly influential in the legal system because juries tend to weigh a witness's confidence heavily when judging the reliability of an identification, and post-identification feedback can artificially inflate exactly those retrospective reports regardless of whether the original identification was actually accurate.