The Effects of Group Discussion on Eyewitness Accuracy

Previous research on group performance in judgmental tasks reveals that groups are rarely inferior, and often superior, to the average individual. The present study examined whether this pattern of results extends to the accuracy of eyewitness reports of a crime. It was found that group discussion led to accounts that were significantly more accurate than the average individual. A requirement to reach a unanimous decision did not alter any of the effects of group discussion. Group superiority was especially clear in terms of the completeness of the reports and in estimations of the duration of the incident. The discussion considered the implications of the present results for the current practice of prohibiting group discussion as an aid to the preparation of testimony.     

The Elusive Effects of Alcohol Intoxication on Visual Attention and Eyewitness Memory

Alcohol is a contributing factor in many crimes, yet little is known of its effects on eyewitness memory and face identification. Some authors suggest that intoxication impairs attention and memory, particularly for peripheral scene information, but the data supporting this claim are limited. The present study therefore sought to determine whether (i) intoxicated participants spend less time fixating on peripheral regions of crime images than sober counterparts, (ii) whether less information is recognised from image regions receiving fewer gaze fixations and (iii) whether intoxicated participants are less able to identify the perpetrator of a crime than sober participants. Contrary to expectations, participants' ability to explore and subsequently recognise the contents of the stimulus scenes was unaffected by alcohol, suggesting that the relationship between intoxication, attention and eyewitness memory requires closer scrutiny. Copyright © 2013 John Wiley & Sons, Ltd.     

Eyewitness Testimony: The Effects of Discussion on Recall Accuracy and Agreement

While some previous research has suggested that group discussion may facilitate eyewitness accuracy, other research has drawn attention to the potential dangers of such discussion. The present studies examine this controversy and the interaction between accuracy and agreement following group discussion. It was found that individuals tend to agree in their testimony following group discussion, and are liable to change their original replies to bring themselves into agreement with group leaders' recall. A second experiment focused upon the actual items which witnesses agreed on following discussion. Changing the mode of questioning from interrogative to narrative eliminated differences in magnitude of agreement between discussion and no-discussion groups. As narrative recall leads to reporting of "easy" items, it was suggested that only certain "difficult" items are susceptible to discussion effects. The need for caution regarding the reliance on testimony following witness discussion was stressed.     

The Effects of Recent Sleep Duration,Sleep Quality,and Current Sleepiness on Eyewitness Memory

This study examined whether three sleep‐related variables (current sleepiness, the duration of the previous night's sleep and the quality of that sleep) were predictors of an eyewitness's ability to remember central and peripheral details from a crime. Participants first completed a self‐report questionnaire assessing their current sleepiness, then watched a video of a bank robbery, next completed a self‐report questionnaire about their previous night's sleep, and then had their memory of the crime tested. It was found that as the eyewitnesses' sleep quality decreased and their sleepiness increased, their ability to accurately recollect peripheral details from the crime was compromised. This is the first demonstration that variations in sleep prior to witnessing a crime, and sleepiness at the time of a crime, can predict eyewitness memory. Copyright © 2013 John Wiley & Sons, Ltd.     

Long‐Term Memory Effects of Eye Closure on Children Eyewitness Testimonies

Previous studies conducted on adults and children found that closing the eyes while recalling an event increased memory accuracy for both free and cued recall. One possible explanation to this phenomenon is that eye closure increases the amount of cognitive resources devoted to the task reducing external stimulation, but it is still not clear whether the beneficial effect is only due to a better focus on the task or to a better encoding of the material leading to an advantage over time. In this study, we evaluated the effect of eye closure instruction on children memory accuracy for a short clip in an immediate and delayed recall. We observed that asking participants to close their eyes while performing a memory task helped them to remember more details and that this effect persisted after a time delay. Copyright © 2012 John Wiley & Sons, Ltd.     

Overcoming Misinformation Effects in Eyewitness Memory: Effects of Encoding Time and Event Cues

Eyewitness memory is often distorted when misleading information is presented to subjects after encoding. Three experiments explored ways to overcome these misinformation effects. In Experiment 1, subjects viewed slides of a robbery, at a rate of four or seven seconds per slide. Five minutes later subjects were given a recognition test with few (1–3) or numerous (6–13) event cues. Providing numerous retrieval cues improved overall performance, but did not reduce the effects of misinformation. W ith week-long delays (Experiment 2) numerous retrieval cues did eliminate misinformation effects, but only when subjects viewed slides at the slower rate (seven seconds per slide). Experiment 3 essentially replicated this pattern, using a modified test to eliminate any biasing effects of distractors. Given adequate encoding and numerous retrieval cues, misinformation effects were eliminated, suggesting that under some conditions misinformation makes event memory inaccessible, but not unavailable.     

Children's Eyewitness Suggestibility: Memory Trace Strength Revisited

This study investigated memory trace strength and the eyewitness suggestibility effect in 5- and 9-year-old children. Children were first presented with a picture story and then, on the next day, were read a post-event summary containing a number of misleading details. Trace strength was manipulated by repetition of the original and/or the post-event details. Children were given either a standard or a modified recognition test on their memories for picture story details one day after presentation of misleading suggestions. Both age groups were found to be suggestible in each recognition test condition. On the modified test, suggestibility was greatest when the post-event trace was strong and the original trace was weak. Theoretical accounts of the suggestibility effect in children and of memory trace strength are discussed in the light of these findings.     

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.     

Adult Eyewitness Memory for Single Versus Repeated Traumatic Events

Reports from individuals who have witnessed multiple, similar emotional events may differ from reports from witnesses of only a single event. To test this, we had participants (N = 65) view a video of a road traffic accident. Half of the participants saw two additional (similar) aversive films. Afterwards, participants filled out the Self‐Administered Interview on the target film twice with an interval of 1 week. Participants who saw multiple similar films were less accurate in recalling details from the target film than participants in the control condition. On their second report, participants were less complete but more accurate compared with their first report. These results indicate that adults who have witnessed multiple repeated events may appear less reliable in their reports than adults who have witnessed a single event. These findings are relevant when evaluating eyewitness evidence and call for new approaches to questioning witnesses about repeated events.Copyright © 2017 John Wiley & Sons, Ltd.     

Enhancing Older Adult Eyewitness Memory with the Cognitive Interview

Thirty older (m age=71.73 years) and 20 young adults (m age=21.60 years) viewed a videotape of a simulated crime and were then interviewed with either a Cognitive Interview (CI) or a standard police interview (SI). The older participants were interviewed with either an SI, CI, or CI that was modified for older people (CI–M). No differences were found between the CI and CI–M. The CI elicited more information than the SI, without a reduction in accuracy rate. Moreover, the advantage of the CI over the SI was greater for the older than for the young participants. There were no overall age-related differences. Results are discussed in terms of performance of older witnesses and implications for understanding how the CI functions.     

Effect of Questioning Techniques and Interview Setting on Young Children's Eyewitness Memory

The goal of this research was to learn if supposed ineffective questioning techniques (e.g., question repetition within the interview) would reduce the accuracy of five-year-olds' eyewitness memory. In the first study, children viewed a slide show depicting a minor crime and were then interviewed either with a standard interview or one which incorporated ineffective questioning techniques. The results indicated that the type of interview did not affect children's eyewitness memory. In a second study, children were presented with the ineffective interview by an authoritative interviewer in a formal office setting. The results again indicated little influence of interview setting or question technique on children's eyewitness memory, identification accuracy, and suggestibility.     

The Discrediting Effect in Eyewitness Testimony1

Loftus (1974) had subjects read summaries of criminal trials that contained the testimony of either credible or discredited prosecution eyewitnesses, and found no effect of discrediting an eyewitness. Instead, almost as many subjects voted guilty with a discredited eyewitness as with a credible eyewitness; this led Loftus to the conclusion that jurors tend to overbelieve eyewitness testimony. Loftus's conclusion was subsequently challenged by others who reported a strong discrediting effect. A series of three experiments using college students was conducted to explore the characteristics of trial summaries that might account for the discrepancy in results, such as inclusion of judicial instructions concerning proof beyond a reasonable doubt, or an eyewitness's reaffirmation of his testimony following discrediting. In all cases, a strong discrediting effect was found. Apparently the discrediting effect appears regardless of wide variation in content of trial summaries. The present data do not support the overbelief claim.     

Effects of Eyewitness Evidence on Plea-Bargain Decisions by Prosecutors and Defense Attorneys1

The present experiment tested the relative impact of two types of eyewitness evidence (identification and non identification) on plea-bargain decisions by prosecutors and defense attorneys. A hypothetical case involving a robbery was mailed to three prosecutors and three defense attorneys in each of 47 states. The subjects were randomly assigned to receive a case in which an eyewitness claimed: (a) the defendant was the criminal (identification), (b) the defendant was not the criminal (non identification), or (c) it was not possible to tell whether the defendant was the criminal (control). Similar to findings with jurors, both prosecutors and defense attorneys underutilized the non identification information in making their plea-bargain decisions. In the case of the prosecutors, there was evidence that the underutilization of eyewitness non identification was at least partially mediated by the prosecutors' predictions of juror reaction to the evidence.     

Double Exposure: The Effects of Repeated Identification Lineups on Eyewitness Accuracy

Eyewitnesses may be asked to identify the same suspect from a lineup on successive occasions. This study explored the effects on eyewitness decisions of repeated same‐suspect lineups, within a 2 × 2 × 2 mixed‐model factorial design. Witnesses to a video crime attempted to identify the culprit from two same‐format lineups (simultaneous or sequential) separated by a 2‐week retention interval (Lineup1, Lineup2) in which a suspect (guilty or innocent) was common to the lineups. We predicted two components of a posited repeated lineup effect: that positive identification errors made at the first lineup would be carried forward rather than corrected at the second lineup and that the number of false identifications of the innocent suspect would rise from first to second lineup. Predictions were supported, with a stronger negative impact of repeated lineups for simultaneous than sequential lineups. Additionally, witnesses who made selections of the guilty suspect and of the innocent suspect at Lineup2 were equally confident and were significantly more confident than witnesses who declined to pick. The results underscore concerns about possible negative outcomes from repeated lineups. Copyright © 2013 John Wiley & Sons, Ltd.