Age differences (or lack thereof) in discriminability for lineups and showups

Abstract

Previous research reveals that showups are an inferior eyewitness identification procedure to lineups, but no single study has compared younger and older adults' identification decisions for both of these procedures. We had witnesses watch a mock crime video and then make an identification decision from a fair lineup, a biased lineup, or a showup that contained the perpetrator or a designated innocent suspect. Receiver operating characteristic (ROC) analysis showed that identification accuracy was higher from a lineup than from a showup for both age groups, even if the lineup was biased. In addition, calibration curves revealed that witnesses were underconfident when choosing from a fair lineup but overconfident when choosing from a showup. These results reinforce prior research asserting the superiority of lineups over showups.