Fast and confident: postdicting eyewitness identification accuracy in a field study

Area of Science:

• Cognitive Psychology
• Forensic Psychology
• Eyewitness Identification

Background:

• Eyewitness identification accuracy is crucial in legal proceedings.
• Postdictive measures like confidence and decision time are explored as indicators of accuracy.

Purpose of the Study:

• To evaluate the combined predictive value of postdecision confidence, decision time, and Remember-Know-Familiar (RKF) judgments on identification accuracy.
• To compare the accuracy of different witness decision strategies, including choosers and nonchoosers.

Main Methods:

• 10 targets and 720 participants were involved in a simulated identification task in a pedestrian area.
• Participants made identifications from target-absent or target-present lineups.
• Decision time, confidence ratings, and RKF judgments were recorded and analyzed.

Main Results:

• Fast (≤6 seconds) and highly confident (≥90%) witnesses demonstrated significantly higher identification accuracy.
• Slow and nonconfident witnesses exhibited markedly lower accuracy.
• Know judgments were linked to better identification performance compared to Familiar judgments.

Conclusions:

• Combined measures of decision time and confidence are strong predictors of eyewitness identification accuracy.
• While effective for choosers, these postdictors require further investigation for nonchoosers.
• Decision strategies of nonchoosers varied, but identification performance did not differ significantly across subgroups.