Eyewitness confidence in simultaneous and sequential lineups: A criterion shift account for sequential mistaken identification overconfidence.

Abstract

Confidence judgments for eyewitness identifications play an integral role in determining guilt during legal proceedings. Past research has shown that confidence in positive identifications is strongly associated with accuracy. Using a standard lineup recognition paradigm, we investigated accuracy using signal detection and ROC analyses, along with the tendency to choose a face with both simultaneous and sequential lineups. We replicated past findings of reduced rates of choosing with sequential as compared to simultaneous lineups, but notably found an accuracy advantage in favor of simultaneous lineups. Moreover, our analysis of the confidence-accuracy relationship revealed two key findings. First, we observed a sequential mistaken identification overconfidence effect: despite an overall reduction in false alarms, confidence for false alarms that did occur was higher with sequential lineups than with simultaneous lineups, with no differences in confidence for correct identifications. This sequential mistaken identification overconfidence effect is an expected byproduct of the use of a more conservative identification criterion with sequential than with simultaneous lineups. Second, we found a steady drop in confidence for mistaken identifications (i.e., foil identifications and false alarms) from the first to the last face in sequential lineups, whereas confidence in and accuracy of correct identifications remained relatively stable. Overall, we observed that sequential lineups are both less accurate and produce higher confidence false identifications than do simultaneous lineups. Given the increasing prominence of sequential lineups in our legal system, our data argue for increased scrutiny and possibly a wholesale reevaluation of this lineup format.

Estimating the reliability of eyewitness identifications from police lineups

“…Thus, it seems fair to conclude that the signal detection analyses weigh against the notion that sequential lineups are diagnostically superior to simultaneous lineups. To the extent that these findings are interpreted as supporting the simultaneous procedure, they are consistent with recent laboratory-based ROC analyses (18)(19)(20)(21).…”

“…4A). In addition, and again contrary to a widely held view, the present results reinforce both ROC analyses of laboratory-based data (18)(19)(20)(21) and another police department field study analysis (22) suggesting that sequential lineups are not diagnostically superior to simultaneous lineups and that the reverse is more likely to be true (although, depending on how the data were analyzed here, the simultaneous advantage was not always significant).…”

“…Those that have been performed found that confident eyewitnesses were more accurate than less confident eyewitnesses (13,14). However, the investigating officer who administered the lineup knew who the suspect was, raising the possibility that this effect merely reflected administrator influence.With regard to lineup format (simultaneous vs. sequential lineups), recent mock crime studies using receiver operating characteristic (ROC) analysis (15-17) have generally found that simultaneous lineups are, if anything, diagnostically superior to sequential lineups (18)(19)(20)(21). Similarly, in a recent police department field study comparing the two lineup formats, expert ratings of evidence against identified suspects favored the simultaneous procedure (22).…”

“…With regard to lineup format (simultaneous vs. sequential lineups), recent mock crime studies using receiver operating characteristic (ROC) analysis (15-17) have generally found that simultaneous lineups are, if anything, diagnostically superior to sequential lineups (18)(19)(20)(21). Similarly, in a recent police department field study comparing the two lineup formats, expert ratings of evidence against identified suspects favored the simultaneous procedure (22).…”

Individual differences in eyewitness identification accuracy between sequential and simultaneous line-ups: consequences for police practice and jury decisions

“…In fact, research has provided strong evidence that eyewitness confidence in identifications may in fact be the greatest predictor of verdict outcomes at trial (Cutler et al, 1990), with reliance on witness confidence shown to be unaffected by traditional safeguards, such as cross-examination . Within the United States, the Supreme Court held that the confidence of eyewitness testimony can be used as a measure of its reliability, alongside determining whether such evidence can be considered admissible during trial (see Dobolyi & Dodson, 2013).…”