Eyewitness metamemory predicts identification performance in biased and unbiased line‐ups

Purpose

Distinguishing accurate from inaccurate identifications is a challenging issue in the criminal justice system, especially for biased police line‐ups. That is because biased line‐ups undermine the diagnostic value of accuracy post‐dictors such as confidence and decision time. Here, we aimed to test general and eyewitness‐specific self‐ratings of memory capacity as potential estimators of identification performance that are unaffected by line‐up bias.

Methods

Participants (N = 744) completed a metamemory assessment consisting of the Multifactorial Metamemory Questionnaire and the Eyewitness Metamemory Scale and took part in a standard eyewitness paradigm. Following the presentation of a mock‐crime video, they viewed either biased or unbiased line‐ups.

Results

Self‐ratings of discontentment with eyewitness memory ability were indicative of identification accuracy for both biased and unbiased line‐ups. Participants who scored low on eyewitness metamemory factors also displayed a stronger confidence–accuracy calibration than those who scored high.

Conclusions

These results suggest a promising role for self‐ratings of memory capacity in the evaluation of eyewitness identifications, while also advancing theory on self‐assessments for different memory systems.