Mistaken Eyewitness Identification Rates Increase When Either Witnessing or Testing Conditions Get Worse

• Published in: Law and human behavior 2019-08, Vol.43 (4), p.358-368
• Main Authors: Smith, Andrew M, Wilford, Miko M, Quigley-McBride, Adele, Wells, Gary L
• Format: Article
• Language: English
• Subjects: Causality; College Students; Criminal Law - methods; Decision Making; Facial Recognition; Human; Human Information Storage; Humans; Identification; Memory; Recognition, Psychology; Students; Witnesses
• ISSN: 0147-7307; 1573-661X
• DOI: 10.1037/lhb0000334

We examined how giving eyewitnesses a weak recognition experience impacts their identification decisions. In 2 experiments we forced a weak recognition experience for lineups by impairing either encoding or retrieval conditions. In Experiment 1 (n = 245), undergraduate participants were randomly assigned to watch either a clear or a degraded culprit video and then viewed either a culprit-present or culprit-removed lineup identification procedure. In Experiment 2 (n = 227), all participants watched the same clear culprit video but were then randomly assigned to either view a clear or noise-degraded lineup procedure. Half of the participants viewed a culprit-present lineup procedure and the remaining participants viewed a culprit-removed lineup procedure. Not surprisingly, degrading either encoding or retrieval conditions led to a sharp drop in culprit identifications. Critically, and as predicted, degrading either encoding or retrieval conditions also led to a sharp increase in the identification of innocent persons. These results suggest that when a lineup procedure gives a witness a weak match-to-memory experience, the witness will lower her criterion for making an affirmative identification decision. This pattern of results is troubling because it suggests that witnesses who encounter lineups that do not include the culprit might have a tendency to use a lower criterion for identification than do witnesses who encounter lineups that actually include the culprit. Public Significance Statement Eyewitnesses lowered their criterion for making an affirmative identification from a culprit-absent lineup when either the witnessing (encoding) or testing (retrieval) conditions were made to be poor. This research helps us understand why eyewitnesses often make affirmative identification decisions under weak memory conditions rather than backing away from making any identification at all. We posit that any condition that leads to an eyewitness having a weak recognition response to a lineup, including the mere absence of culprit in the lineup, will result in eyewitnesses using a lowered criterion for making an affirmative decision.