An Archival Study of Eyewitness Memory of the Titanic's Final Plunge

A handful of real-life studies demonstrate that most eyewitnesses accurately recall central details (i.e., the gist of what happened) from traumatic events. The authors evaluated the accuracy of archival eyewitness testimony from survivors of the Titanic disaster who witnessed the ship's final plunge. The results indicate that most eyewitness testimony (15 eyewitnesses of 20) is consistent with forensic evidence that demonstrates that the Titanic was breaking apart while it was still on the ocean's surface. Despite the methodological limitations of archival research, the authors provide evidence from a single-occurrence traumatic event (with a large-scale loss of life) that the majority of eyewitnesses accurately recall central details.     

Degree of Detail of Eyewitness Testimony and Mock Juror Judgments1

The influence of the degree of detail of eyewitness testimony on two sides of a court case was investigated in two experiments. In the first experiment subject-jurors read a civil court case involving an automobile-pedestrian accident. The plaintiff and the defendant presented conflicting eyewitness accounts. Judgments of the relative credibility of the eyewitnesses on each side and the percentage of negligence of the parties were influenced by the relative degree of detail of the eyewitness testimony on each side. In the second experiment subject-jurors read a criminal court case involving robbery and murder. The prosecution and defense presented conflicting eyewitness accounts. The degree of detail of the prosecution eyewitness testimony influenced judgments of guilt and judgments of the credibility of the eyewitnesses. An examination of the reasons for verdicts and credibility judgments revealed that some subjects inferred that an eyewitness who gave testimony with a greater degree of detail had a better memory for the trivial details and the culprit than an eyewitness who gave testimony with a lesser degree of detail. Implications of these results for the legal system are discussed.     

The effects of repeatedly recalling a traumatic event on eyewitness memory and suggestibility

ABSTRACT

The aims of this study were to examine the effects of repeatedly recalling a traumatic event on recall performance and eyewitness suggestibility. We also investigated whether these effects were moderated by the type of details recalled and the completeness of retrieval. Participants watched a video depicting a fatal car accident and were randomly allocated to one of four conditions in which they: (1) repeatedly recalled the traumatic (central) details of the event only (trauma-focused); (2) repeatedly recalled the non-traumatic (peripheral) details of the event only (non-trauma focused); (3) repeatedly recalled the entire video (complete); or (4) did not recall the video at all (no-recall control). Results indicated that repeated complete recall was beneficial for memory retention of the entire traumatic event and that, in general, trauma-related (central) post-event information (PEI) was less likely to be reported than trauma-unrelated (peripheral) PEI. It was also found that repeated trauma-focused recall increased trauma-related confabulations. These results not only illustrate the value of repeated complete recall to best preserve the integrity of eyewitness memory, but, perhaps more critically, warn of the dangers of repeatedly questioning witnesses specifically about the central or traumatic details of an event.     

Truth and Consequences: The Effect of Responsibility on Eyewitness Behavior

Previous research has revealed that eyewitness identification errors are so common as to render such testimony of questionable value as courtroom evidence. However, all of this research was conducted in settings where the eyewitnesses were not responsible for the consequences of their responses—that is, they were aware they were in an experiment. The present research compared eyewitness behavior in an explicitly experimental setting with behavior in a setting that the subjects perceived to be real and in which loss of time, potential embarrassment and discomfort, a student's reputation, and the validity of a scholarship competition were at stake. Surprisingly, two studies both found that subjects were just as willing to offer information, just as willing to make a positive identification, and just as inaccurate in the real as in the experimental setting. These results indicate that previous research has accurately portrayed eyewitness error rates in actual investigations. Implications of the present research for the use of eyewitness testimony are discussed.     

Testifying on Eyewitness Reliability: Expert Advice Is Not Always Persuasive1

This study investigates the impact of different types of expert testimony regarding the unreliability of eyewitness identification. In two hypothetical court cases involving eyewitnesses, expert testimony was presented that was either sample-based (presenting the results of a research program on eyewitness identification) or person-based (presenting information about the particular eyewitness under consideration); the expert either offered causal explanations for his unreliability claim or failed to do so. Two additional control groups (with and without eye-witness identification) were not presented with any expert testimony. The results indicate that subjects who had been confronted with an expert statement made more lenient judgments about the offender but did not discount the eyewitness identification completely. Sample-based information had a moderate impact on the subjects' judgments, regardless of whether or not causal explanations were given. Person-based testimony was the most influential type of expert advice when a causal explanation was provided but the least influential one when no reasons were given. The practical (international differences in admissibility of expert testimony) and theoretical implications (processing of base-rate information) of these findings are discussed.     

The Influence of Eyewitness Nonidentifications on Mock-Jurors' Judgments of a Court Case1

Two experiments examined the effect of an eyewitness nonidentificution on mock-jurors' verdicts in robbery cases, as well as the effects of number of identifying eyewitnesses and status of the identifying witness (victim or bystander). Subjects read court case summaries that included variable eyewitness evidence and constant alibi, circumstantial, and character evidence. In Experiment 1, frequency of guilty verdicts was significantly less when an eyewitness testified in court that the defendant was not the perpetrator, even when this nonidentification opposed two positive identifications. In Experiment 2, a low guilty rate was again associated with the presence of a nonidentifier, but only when the nonidentifier actually testified in court and stipulated that the defendant is “not the man.” On the average, 70% of the jurors delivered guilty verdicts when both the victim and bystander gave identifying testimony, whereas 12.5% delivered guilty verdicts when the bystander gave opposing nonidentifying testimony. Guilty rates were unaffected by the identifying eyewitness' status and (in Experiment 2, but not Experiment 1) were higher when there were two (vs. one) identifying eyewitnesses.     

Eyewitness Errors in the Free Recall of Actions

Although eyewitness testimony is often unreliable, its quality is not uniformly poor. Previous research indicates that the most accurate type of testimony involves the unstructured recall of actions. The present study replicates the finding that confabulation, particularly the complete fabrication of nonexistent actions, is rare. Our results also extend earlier work by revealing that the few errors that did occur were spread evenly across subjects—with most subjects making 0 or 1 error and with no subjects making more than 3 errors. Furthermore, action memory errors form a heterogeneous set—there were few commonly recurring or predictable errors. Our attempts to increase error frequency by the use of suggestive implications and rapid action sequences were unsuccessful. Practical aspects of evaluating action memory testimony are discussed, with special reference to cases involving multiple eyewitnesses.     

Cross-cultural differences in eyewitness memory reports

Increasingly, investigators conduct interviews with eyewitnesses from different cultures. The culture in which people have been socialised can impact the way they encode, remember, and report information about their experiences. We examined whether eyewitness memory reports of mock witnesses from collectivistic (sub-Saharan Africa) and individualistic (Northern Europe) cultures differed regarding quantity and quality of central and background details reported. Mock witnesses (total N = 200) from rural Ghana, urban Ghana, and the Netherlands were shown stimuli scenes of crimes in Dutch and Ghanaian settings and provided free and cued recalls. Individualistic culture mock witnesses reported the most details, irrespective of detail type. For each cultural group, mock witnesses reported more correct central details when crime was witnessed in their own native setting than a non-native setting, though for different recall domains. The findings provide insight for legal and investigative professionals as well as immigration officials eliciting memory reports in cross-cultural contexts.     

Evaluating Identification Evidence from Multiple Eyewitnesses

When two or more eyewitnesses provide identification evidence in a given investigation, their testimony will be characterized either by unanimity or by contradictions. In the present research, nominal groups of several sizes were constructed from the distributions of individual responses in a variety of previous studies. It was found that both unanimity and contradictions could be expected to occur with considerable frequency. When unanimity occurred, the unanimous response was very likely to be accurate, particularly in large groups. When contradictions occurred, the most common, or modal, response was most probably accurate, particularly when four or more witnesses endorsed the modal position. These and several subsidiary findings resulted largely from the fact that individual errors were randomly distributed across many different incorrect response options. Consequently, even when eyewitnesses were generally inaccurate, the correct option was still chosen more frequently than any single incorrect option. Distinctions between the implications of individual vs. multiple eyewitness testimony were discussed.     

Being a good witness: The roles of benevolence and working memory capacity in rapport’s effect on eyewitness memory

Prior studies suggest that building rapport with eyewitnesses can produce measurable recall improvements, but the underlying mechanisms of rapport’s possible effects on recall remain underexplored. The present study investigated two possible mechanisms for rapport’s impact: (1) improved working memory capacity and (2) increased benevolence. Participants (N = 105) viewed a mock theft video, followed by one of two possible pre-interview interactions: rapport-building or a control interaction. Next, participants completed measures of working memory, altruism, and benevolence (pre-interview and post-interview), before recalling details of the theft. Analyses revealed that, when controlling for the effects of the interaction duration and participants’ pre- and post-interview benevolence, rapport did not affect eyewitness recall directly. However, rapport building did increase benevolence measured after and associated with the substantive eyewitness interview, which in turn predicted more accurate and new details reported, and fewer subjective/other details reported. These findings support benevolence toward the interviewer as a mechanism behind rapport’s effect on eyewitness recall. Implications for investigative interviews in relation to benevolence and motivating reciprocation are discussed.     

Effect of personal involvement in traumatic events on memory: The case of the Dolphinarium explosion

The association between memories of the terrorist explosion at the Dolphinarium discotheque in Tel Aviv and the level of personal involvement in the explosion was investigated. Memories of injured victims, uninjured eyewitnesses, and uninvolved controls who learned about the explosion from the mass media were compared. It was expected that memory of the explosion would be most and least detailed and accurate among the victims and the controls, respectively. The participants responded to an open-ended question about the explosion, as well as to specific and multiple-choice questions. Data analyses showed that the victims and the eyewitnesses remembered more details than the controls, and that the victims remembered both central and peripheral details more accurately than the other participants. Degree of involvement in the same traumatic experience was thus shown to be differentially associated with memory accuracy.     

Examining the generality of eyewitness hypermnesia: A close look at time delay and question type

Three studies investigated whether requiring eyewitnesses to provide multiple accounts of a crime prompted them to exhibit more accurate and complete recall (i.e. hypermnesia) or towards providing more inaccurate and confabulated testimony. Subject-witnesses viewed videotapes enacting several types of crimes. Subjects exhibited hypermnesia in two studies in which they were asked to provide accounts of the incident via a free-recall procedure. Indeed, there tended to be roughly a 10–20 per cent increase in the number of facts accurately recalled from the initial interview to the third. The number of incorrect recollections and confabulations did not reliably increase. In the second experiment, hypermnesia was observed even when eyewitness memory was degraded by delaying the initial interview until a week after the witness viewed the crime. In a third study, which employed a multiple-choice questioning procedure, subjects exhibited neither hypermnesia nor heightened incorrect responding. Discussion centres on possible factors influencing the hypermnesia effect and implications of the present research for theory on hypermnesia.     

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.     

Recalling a Witnessed Event Increases Eyewitness Suggestibility: The Reversed Testing Effect

ABSTRACT— People's later memory of an event can be altered by exposure to misinformation about that event. The typical misinformation paradigm, however, does not include a recall test prior to the introduction of misinformation, contrary to what real-life eyewitnesses encounter when they report to a 911 operator or crime-scene officer. Because retrieval is a powerful memory enhancer (the testing effect), recalling a witnessed event prior to receiving misinformation about it should reduce eyewitness suggestibility. We show, however, that immediate cued recall actually exacerbates the later misinformation effect for both younger and older adults. The reversed testing effect we observed was based on two mechanisms: First, immediate cued recall enhanced learning of the misinformation; second, the initially recalled details became particularly susceptible to interference from later misinformation, a finding suggesting that even human episodic memory may undergo a reconsolidation process. These results show that real-life eyewitness memory may be even more susceptible to misinformation than is currently envisioned.     

Process versus content in eyewitness metamemory monitoring

Three studies (Ns = 200, 135, and 187 college undergraduates) contrasted process versus content accounts of eyewitness metamemory monitoring. Subjective vividness, a cue related to memory content, was a better predictor of confidence and accuracy than were cues related to the retrieval process. Participants who were asked to recall, rather than recognize, event details displayed greater insight into accuracy, primarily because vividness was a more valid accuracy cue under recall conditions. Results reinforce the value of recall-based protocols for eliciting eyewitness testimony and suggest some specific conditions (e.g., yes-no recognition) under which investigators should be especially cautious in relying on confidence to infer accuracy. In addition, results point to a general framework for understanding moderating effects on eyewitness metamemory accuracy.     

Effects of racial stereotypes on eyewitness performance: Implications of the real and the rumoured Allport and Postman studies

The Allport and Postman (1945, 1947) study of rumour has been widely cited in support of the claim that expectations based upon racial stereotypes can cause eyewitnesses to make dramatic errors in perceiving or remembering an event. However, this claim is founded on inaccurate accounts of the study that have appeared throughout the eyewitness testimony literature. In this article we explore the implications of the actual Allport and Postman study, and the study as erroneously described, for questions about eyewitness performance.     

心理学关于目击证人证言可靠性实证研究

目击证人的证词在刑事诉讼中有着极为重要的作用,但是由于证人对案件的记忆往往会受到其自身和外界各种因素的干扰,因此,对于目击证人证词可靠性的研究引起了心理学界的关注,西方心理学界自上个世纪七十年代以来,从证人的年龄性别、心理状态、对证人的询问方式以及辨认的情景等方面进行了大量的实证研究,为司法实践提供了重要的启示。本文从以上四个方面全面总结了西方心理学界关于证人证词可靠性的实证研究,并作了分析与展望。     

Eyewitness memory: The impact of a negative mood during encoding and/or retrieval upon recall of a non-emotive event

The police often appeal for eyewitnesses to events that were unlikely to have been emotive when observed. An eyewitness, however, may be in a negative mood whilst encoding or retrieving such events as mood can be influenced by a range of personal, social, and environmental factors. For example, bad weather can induce a negative mood. This experiment compared the impact of negative and neutral moods during encoding and/or retrieval upon eyewitness recall of a non-emotive event. A negative mood during encoding had no impact upon the number of correct details recalled (provided participants were in a neutral mood at retrieval) but a negative mood during retrieval impaired the number of correct details recalled (provided participants were in a neutral mood at encoding). A negative mood at both time points enhanced the number of correct details recalled, demonstrating a mood-dependent memory enhancement. The forensic implications of these findings are discussed.