The Effect of Mugshot Inspections on Eyewitness Identification Accuracy1

This study assessed the effect of commitment to an earlier mugshot identification on the ability to make a subsequent lineup identification. Shortly after viewing videotape of a staged assault some subjects rated a group of 18 photos for attractiveness, whereas other subjects attempted to identify the assailant publicly or privately in the same (target-absent) set of 18 “mugshot” photos. The remaining subjects had no intervening task. Two days later, all subjects attempted to identify the assailant from a six-person target-present photo lineup which contained their mugshot choice (if made) as well as the original assailant. Lineup identifications were significantly less accurate for subjects who had viewed the intervening mugshots (33% accuracy) than those who had only rated the intervening photos for attractiveness (64% accuracy) or had seen no intervening photos (69% accuracy). When viewing lineups, experimental subjects tended to remain committed to their earlier action of choosing or not choosing anyone from the mugshots. More witnesses who had publicly stated their mugshot choice reproduced their (incorrect) choice at the lineup (78%), than did those who made a private mugshot choice (45%), though this difference was not statistically reliable. Witnesses' confidence in their lineup decision was not significantly related to overall accuracy. Contrary to predictions from self-perception theory, confidence in one's decision decreased significantly as further identifications were attempted.     

Witnesses’ memories for lineup fillers postdicts their identification accuracy

Witnesses who have quick, automatic recognition experiences when viewing a lineup tend to make more accurate decisions than witnesses who engage in slower, more deliberative processes. A novel postdictor of identification accuracy is predicted from these findings: memories for lineup fillers should be stronger among inaccurate, rather than accurate, witnesses. Undergraduate students (N = 320) viewed a mock crime, made a lineup identification decision, and were given a surprise test for their memory for the lineup fillers. Consistent with predictions, better memories for lineup fillers postdicted mistaken identifications and the suspect's innocence. Information gain analyses showed that under some conditions, memory for lineup fillers provided as much information about the suspect's guilt as a lineup identification. Findings are consistent with the idea that postdictors of eyewitness accuracy are valuable to the extent that they measure the automaticity or deliberativeness of the witness's experience when viewing the lineup.     

Does Knowledge that a Crime Was Staged Affect Eyewitness Performance?1

The Staged crime has generally been considered a valid paradigm for assessing eyewitness identification accuracy. Yet the typical procedure informs the witness before the lineup task that the event was staged. The current study manipulated whether or not witnesses were informed that the witnessed crime was staged (information variable). Two other variables, the presence or absence of the perpetrator in the photo-lineup and the physical similarity of lineup members, were manipulated to asses any possible interactions with the information variable. A theft was staged individually for 184 unsuspecting witnesses who were then randomly assigned to be either informed that the theft was staged or not informed. Next, all witnesses were met by a uniformed security officer who showed them a photo-lineup of six individuals. Half of the witnesses viewed a perpetrator-present lineup with either high or low physical similarity between the foils and the perpatrator and half viewed a perpetrator-absent lineup with either high or low physical similarity. Three confidence measures, one cooperation measure, and an Embedded Figures Test score were obtained. The results showed that (a) the information variable did not affect the likelihood that a witness would attempt an identification; (b) the information variable did not have a main effect on the particular choices made by the witnesses nor did it interact with lineup similarity, but it did interact with the presence-absence variable; and (c) the information variable did not affect witness confidence either as a main effect or interaction effect, but, was relatively consistent in affecting the correlation between confidence and accuracy such that the correlation was lower for witnesses who were not informed. The interaction between the information variable and the presence-absence variable on accuracy was due to the uninformed witnesses being less accurate than the informcd witnesses in the perpetrator-present condition. The results suggest that accuracy among actual eyewitnesses may be lower than obtained in the typical staged crime procedure and that accuracy-confidence correlations may be overestimated by the typical staged crime.     

The confidence-accuracy relationship in eyewitness identification: the effects of reflection and disconfirmation on correlation and calibration

Participants viewed a simulated crime and attempted an identification from an 8-person target-present or target-absent lineup. The authors examined identification confidence-accuracy relations, contrasting a control condition (n = 310) with 2 manipulations designed to improve confidence scaling. Before indicating confidence, participants reflected on encoding and identification test conditions (n = 316) or suggested hypotheses about why their identification decision might have been wrong (n = 318). Confidence-accuracy correlations were weak and did not differ across conditions. However, for positive identifications, confidence and accuracy were well calibrated in the experimental conditions, although not in the control condition; similar patterns were observed for lineup rejections. Explanations for calibration differences in terms of discrimination difficulty, (mis)match between encoding and test stimuli, and the availability of confidence cues were advanced.     

The effect of biased lineup instructions on eyewitness identification confidence

Although it is well‐known that biased lineup instructions (i.e., those that do not inform witnesses the perpetrator may not be in the lineup) inflate false identifications, their effects on witness confidence are less well understood due to methodological limitations of past studies. We report two studies that use novel methodologies to obviate these limitations. Study 1 (N = 177) demonstrated that biased lineup instructions increased witnesses' average estimates of the likelihood that a lineup member is guilty. Study 2 (N = 137) introduces a novel debiasing paradigm that allows a parsing of choosers into those who made an identification only because of the biased instructions (induced choosers), and those who would have chosen despite the instructions (inherent choosers). Biased lineup instructions inflated confidence only among induced choosers, but not among inherent choosers. Contrary to legal reasoning, witness confidence is an insufficient metric to determine the suggestiveness of biased instructions.     

The Psychology of Lineup Identifications1

A review is made of issues and data on eyewitness identifications, and a relative-judgment conceptualization is proposed. It is argued that eyewitnesses are prone to choose the lineup member who most resembles the perpetrator relative to other lineup members as evidenced by studies that manipulated similarity of lineup members. The relative-judgment strategy is fallacious because of the unpredictable occurrence of target-absent lineups and is not corrected fully by instructions to eyewitnesses. An extension of the relative-judgment conceptualization proposes an inverse relationship between the goodness of witnesses' memories (quality and quantity of relevant information available in memory) and witnesses' tendencies to rely on relative judgments. This extended conceptualization was used to derive expectations regarding an experiment (N= 192 eyewitnesses) that used a blank lineup prior to presenting eyewitnesses with the actual lineup. The data indicated that a blank lineup can yield a diagnostic split of eyewitnesses; those who made no identification when presented with a blank lineup were less likely to make false identifications on the actual lineup than either the witnesses who identified someone from the blank lineup or the witnesses who were not presented with a blank lineup. The blank lineup did not produce a significant loss in accurate identifications. The practical implications of using blank lineups and the theoretical utility of the relative-judgment conceptualization are discussed.     

Absolute and Relative Decision Processes in Eyewitness Identification

A prominent and long-standing theory of eyewitness identification decision making distinguishes between absolute judgments, based on the lineup members' match to the witness's memory of the perpetrator, versus relative judgments, based on match values relative to other lineup members. This distinction was implemented in a computational model and simulations showed that the model predicts an accuracy advantage for absolute judgments over relative judgments under some conditions. The present experiment tested this prediction by evaluating the accuracy of witnesses instructed to use relative or absolute rules. Contrary to predictions, the overall analysis did not show an absolute advantage. Additional exploratory analyses showed a relative advantage when the suspect was surrounded by high-similarity foils. These results are consistent with a model that assumes that side-by-side comparisons of lineup members increase diagnostic accuracy by allowing witnesses to give greater weight to more diagnostic features and less weight to less diagnostic features.     

Asking an eyewitness to predict their later lineup performance could harm the confidence–accuracy relationship

Few studies have investigated eyewitnesses' ability to predict their later lineup performance, known as predecision confidence. We applied calibration analysis in two experiments comparing predecision confidence (immediately after encoding but prior to a lineup) to postdecision confidence (immediately after a lineup) to determine which produces a superior relationship with lineup decision accuracy. Experiment 1 (N = 177) featured a multiple-block lineup recognition paradigm featuring several targets and lineups; Experiment 2 featured an eyewitness identification paradigm with a mock-crime video and a single lineup for each participant (N = 855). Across both experiments, postdecision confidence discriminated well between correct and incorrect lineup decisions, but predecision confidence was a poor predictor of accuracy. Moreover, simply asking for predecision confidence weakened the postdecision confidence–accuracy relationship. This implies that police should exercise caution when interviewing eyewitnesses, as they should not be asked to predict their ability to make an accurate lineup decision.     

The Effects of the Cognitive Interview on Recall,Identification, Confidence and the Confidence/Accuracy Relationship

The effects of two interview techniques, the Cognitive Interview (CI) and the Structured Interview (SI), were examined in relation to recall, recognition, confidence and the confidence/accuracy relationship. Volunteer subjects witnessed a live staged event, and at set time delays (48 and 96 hours) were interviewed by means of either the CI or SI and made lineup identifications from both blank and filled lineup presentations. The CI significantly improved total recall (p<0.001) and correct recall (p<0.001) relative to the SI. There were no differences in either accuracy or error rates for the two conditions. The CI produced significantly higher ‘pre-post interview’ confidence ratings than the SI (p<0.05). Within-, between- and event-confidence ratings were not predictive of recall or recognition accuracy. Failure to find a significant consistent confidence/accuracy relationship was suggested to have occurred because of the operation of an accuracy assessment heuristic. The CI did not reliably improve identification from a filled lineup presentation relative to the SI, but did produce better performance on a blank lineup presentation (p<0.001). Confidence and the confidence/accuracy relationship involving identifications were not found to differ as a function of interview condition. Throughout the study multiple regression analyses failed to reveal consistent predictors of recall or recognition accuracy, confidence or the confidence/accuracy relationship of these two domains. © 1997 by John Wiley & Sons, Ltd.     

Postidentification feedback affects subsequent eyewitness identification performance

Eyewitnesses sometimes view more than one lineup during an investigation. We investigated the effects of postidentification feedback following one lineup on responses to a second lineup. Witnesses (N=621) viewed a mock crime and, later, attempted to identify the culprit from an initial (target-absent) lineup and a second (target-present or target-absent) lineup. Prior to viewing the second lineup, some witnesses received accurate feedback stating that the initial lineup did not contain the culprit. A compound-decision, signal detection approach allowed the effects of feedback on identification responses to be described in terms of differences in discriminability and response bias. For witnesses who made an incorrect foil identification from the initial lineup, feedback (vs. no feedback) was associated with poorer discriminability on the second test. For witnesses who correctly rejected the initial lineup, feedback (vs. no feedback) was associated with greater discriminability on the second test. Only witnesses who received feedback after an initial correct rejection performed at a level comparable with a single-lineup control group, suggesting that an initial identification test can impair, but not enhance, performance on a second test involving the same culprit. From a theoretical perspective, the results are consistent with the idea that the way people use memorial information when making memory decisions is flexible. Analyses of preidentification confidence ratings, obtained in a follow-up study (N=133), suggested that the effects of feedback on identification performance may have operated via differences in witnesses' metacognitive beliefs.     

Post‐identification feedback effects: Investigators and evaluators

We investigated the effects of post‐identification feedback and viewing conditions on beliefs and interviewing tactics of participant‐investigators, crime reports of participant‐witnesses and participant‐evaluators' credibility judgments of the witnesses. Study 1 participants assumed the roles of witness and investigator (N = 167 pairs). Witnesses' view of a simulated crime video was manipulated by distance from viewing monitor: 2 or 9 ft. Participants made a line‐up identification and received either positive feedback or no feedback. Significant effects for witnesses and investigators were associated with viewing condition and post‐identification feedback. Interviews between investigator‐witness pairs were videotaped. Investigators asked more positive, leading questions when they were led to believe that the witness had identified the suspect. In Study 2 evaluators (N = 302) viewed the witness‐investigator interviews. Viewing condition had no effect on judgments of witness credibility but positive post‐identification feedback led evaluators to judge witnesses as more credible than witnesses who received no feedback. Copyright © 2010 John Wiley & Sons, Ltd.     

The elimination‐plus lineup: Testing a modified lineup procedure with confidence

The present study examined whether a modified form of a preidentification confidence rating would provide evidence of a suspect's guilt in addition to the identification decision confidence. Participants (N  = 241) viewed a videotaped mock crime and were presented with a target‐present or target‐absent simultaneous, sequential, elimination, or elimination‐plus lineup procedure; both elimination procedures required 2 separate judgments from the witness (i.e., relative and absolute). The elimination‐plus procedure was identical to that of the elimination procedure with the addition of the confidence rating in between judgment 1 and judgment 2. Confidence after judgment 1, confidence after judgment 2, and the average of the 2 confidence ratings with the elimination‐plus procedure significantly predicted accuracy for choosers. Given that confidence has been recognised by the Supreme Court of the United States, these results shed light on a novel way of utilising confidence in the investigative process.     

Anger in lineup identification and creation

As an approach-oriented emotion, anger appears to affect behavioral thresholds in a range of contexts. The current work consists of three experiments examining this in the context of eyewitness identification procedures. Experiments 1 and 2 examined the relationship between a witness' anger and identification reliability, and Experiment 3 examined the relationship between a lineup creator's anger and the quality of selected lineup fillers. Experiments 1 and 2 showed that anger during an identification procedure is associated with increased risk of false identifications and reduced confidence-accuracy calibration. Experiment 3 showed that anger is associated with lower quality of fillers selected by lineup creators. Together, these experiments suggest that anger may undermine the quality of eyewitness evidence, even when the witnesses themselves are not the ones experiencing anger and even when anger is not directed at the perpetrator or suspect.     

Novel lineup methods for improving the performance of older eyewitnesses

Previous research shows that older witnesses demonstrate poorer lineup performance compared to younger adults. Two experiments are presented which investigated the effectiveness of pre‐identification procedures aimed to reduce false identifications made by older adults. In experiment one older adults' demonstrated poorer lineup performance compared to younger adults. However, older adults benefited from pre‐lineup questions and a practice lineup prior to viewing a target absent (TA) lineup. In a second experiment, participants in the practice lineup condition made significantly fewer false identifications and more correct rejections on two TA lineups compared to participants in the control condition. On both target present (TP) lineups there was no significant difference in lineup performance between the two conditions. The effect of pre‐identification procedure on self‐reported lineup decision strategy and memory for non‐biased lineup instructions are discussed, as well as future research directions. Copyright © 2009 John Wiley & Sons, Ltd.     

Post‐identification feedback,confidence and recollections of witnessing conditions in child witnesses

Eyewitness confidence and detailed memory reports are often considered reliable indicators of the credibility of the eyewitness testimony. This study investigated how feedback concerning the accuracy of a lineup identification influences witnesses' confidence in the accuracy of their identification decision and their judgements concerning the witnessing experience. Fifty‐seven children (11–12 years) and 55 adults (17–39 years) viewed a video of a robbery and attempted to identify the culprit from a photo lineup. The culprit was not present. Participants received confirming feedback, disconfirming feedback, or no feedback on the accuracy of their identification. The confidence judgements and recollections of witnessing conditions of both children and adults were influenced by confirming and in some instances, disconfirming feedback. These findings imply that confidence and memory reports are easily distorted by non‐specific feedback and investigators should be sensitive to this particularly when dealing with vulnerable witnesses such as children. Copyright © 2004 John Wiley & Sons, Ltd.     

Effects of postidentification feedback on eyewitness identification and nonidentification confidence

Two experiments investigated new dimensions of the effect of confirming feedback on eyewitness identification confidence using target-absent and target-present lineups and (previously unused) unbiased witness instructions (i.e., "offender not present" option highlighted). In Experiment 1, participants viewed a crime video and were later asked to try to identify the thief from an 8-person target-absent photo array. Feedback inflated witness confidence for both mistaken identifications and correct lineup rejections. With target-present lineups in Experiment 2, feedback inflated confidence for correct and mistaken identifications and lineup rejections. Although feedback had no influence on the confidence-accuracy correlation, it produced clear overconfidence. Confidence inflation varied with the confidence measure reference point (i.e., retrospective vs. current confidence) and identification response latency.     

When accurate and inaccurate eyewitnesses look the same: a limitation of the ‘pop‐out’ effect and the 10‐ to 12‐second rule

Research has found support for a ‘pop‐out effect’ that occurs when witnesses who accurately identify a criminal from a lineup are faster and uses more automatic processing than inaccurate witnesses who misidentify a foil. We present evidence that this finding may not occur with biased lineups. Witnesses to a mock theft were asked to make a lineup identification and three types of witnesses were compared: (1) accurate witnesses who identified a thief, (2) inaccurate witnesses who misidentified a foil who was more similar looking to the thief than the other lineup foils and (3) inaccurate witnesses who misidentified a foil who was not more similar in appearance to the thief than the other lineup foils. Accurate witnesses who identified the thief and inaccurate witnesses who misidentified a foil more similar to the thief than the other lineup foils were indistinguishable; both were faster, used more automatic recognition processes and were more confident than inaccurate witnesses who identified other foils. Copyright © 2006 John Wiley & Sons, Ltd.     

Exposure duration: Effects on eyewitness accuracy and confidence

The current study examined the relationship between the length of exposure to a face in an eyewitness setting and identification accuracy and confidence. A sample of 164 young (ages 17–25) and older (ages 59–81) adults viewed a simulated crime in which they saw the culprit's face for a short (12 s) or long (45 s) duration. They were then tested with a target absent (a line‐up not containing the culprit) or target present line‐up. Identification accuracy rates for both young and older participants were significantly higher under the long exposure condition. In the short exposure condition, witnesses who had made a correct identification of the target were more confident than incorrect witnesses. In the long exposure condition the confidence ratings of accurate and inaccurate witnesses did not differ. Discussion focuses on the extent to which extended exposure may inflate confidence judgments and variables that may moderate the relationship between exposure duration and face recognition accuracy.     

The benefits of knowing what you know (and what you don’t): How calibration affects credibility

People tend to believe, and take advice from, informants who are highly confident. However, people use more than a mere “confidence heuristic.” We believe that confidence is influential because—in the absence of other information—people assume it is a valid cue to an informant’s likelihood of being correct. However, when people get evidence about an informant’s calibration (i.e., her confidence-accuracy relationship) they override reliance on confidence or accuracy alone. Two experiments in which participants choose between two opposing witnesses to a car accident show that neither confidence nor accuracy alone explains judgments of credibility; rather, whether a person is seen as credible ultimately depends on whether the person demonstrates good calibration. Credibility depends on whether sources were justified in believing what they believed.     

Effects of cannabis on eyewitness memory: A field study

Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field setting. One hundred twenty visitors of coffee shops in Amsterdam viewed a videotaped criminal event, were interviewed about the event, and viewed a target‐present or target‐absent lineup. Witnesses under the influence of cannabis remembered significantly fewer correct details about the witnessed event than did sober witnesses, with no difference in incorrect recall. Cannabis use was not significantly associated with lineup identification performance, but intoxicated witnesses were significantly better at judging whether their lineup identification was accurate. Theoretical and practical implications of the findings are discussed.