Eyewitness Decision Processes: A Valid Reflector Variable

Abstract

Identification accuracy can be predicted from eyewitnesses' self-reported decision processes but the evidence of their ability to improve prediction when confidence and response time are included is mixed and minimal. Typically, decision processes are measured via one or five self-report questions; we explored whether a more nuanced questionnaire could improve prediction. Participants viewed a mock-crime video, made a target-present or -absent lineup decision, and completed 17 decision process items. An exploratory factor analysis on choosers' (n = 391) responses revealed three correlated factors, broadly reflecting automatic response, relative judgment, and absolute judgment. The three-factor solution had good internal reliability (McDonald's ωs = 0.93, 0.89, and 0.74, respectively). Scores produced from the questions loading on the automatic response and relative judgment factors improved predictions of accuracy compared to using confidence and response time alone. Self-reported decision processes may be an easy-to-administer and useful reflector of identification accuracy.