Testing eyewitness memory

This study identifies a memory-testing procedure that is relatively resistant to the documented effects of suggestibility on eyewitness memory. Most studies on suggestibility have used averbal recognition memory test in which the alternative test items are sentences, each to be verified as true or false regarding an originally viewedvisual sequence. In this study, participants were tested with either the verbal recognition memory test typical of studies demonstrating the eyewitness suggestibility effect or a visual recognition memory test. The typical eyewitness suggestibility effect resulted in the verbal test condition. However, with the visual recognition memory test, the hit rates did not significantly differ between the control and misled conditions. Thus, in testing memory for a visual event, a visual recognition memory test is more resistant to the influences of suggestibility than is a verbal test. These results suggest that the original item is preserved in memory, not overwritten by the misleading information. Accordingly, with a visual recognition memory test, the original information is more likely to be recovered with a visual recognition memory test than with a verbal one.     

Age differences in eyewitness testimony

This study examined age differences in eyewitness testimony. Children, three and six years of age, and adults interacted with an unfamiliar man for 5 minutes. Four or five days later, the witnesses answered objective and suggestive questions, recalled what happened, and tried to identify the confederate from a target-present photo line-up. The adults and 6-year-olds did not differ in their ability to answer objective questions or identify the confederate, but 6-year-olds were more suggestible than adults and recalled less about the event. Compared to the older age groups, the 3-year-olds answered fewer objective questions correctly, recalled little about what happened, and identified the confederate less frequently. In addition, they were the most suggestible. The experiment extends our knowledge of children's ability to provide accurate eyewitness reports to a very young age group and to a situation in which participants are not merely bystander witnesses but instead directly interact with the confederate.     

Expert testimony about eyewitness identification

Recent research concerning eyewitness identification is surveyed with respect to its adequacy (reliability and validity) to support expert testimony. The conclusion is that the scientific basis is generally inadequate and that the more we have learned about various aspects of eyewitness identification, the most inadequate it appears. The argument is made that presentation in policy settings requires greater circumspection than would be required in presentation to scientific audiences. Prudential rules are suggested. They would have the effect of sharply reducing participation in the adversarial system.     

The reliability of eyewitness identification

This study examines the effects of 14 estimator variables (e.g., disguise of robber, exposure time, weapon visibility) and system variables (e.g., lineup instructions, exposure to mugshots) on a number of measures of eyewitness performance: identification accuracy, choosing rates, confidence in lineup choice, relation between confidence and identification accuracy, memory for peripheral details, memory for physical characteristics of target, and time estimates. Subjects viewed a videotaped reenactment of an armed robbery and later attempted an identification. Characteristics of the videotape and lineup task were manipulated. Prominent findings were as follows: identification accuracy was affected by both estimator and system variables including disguise of robber, weapon visibility, elaboration instructions, and lineup instructions. Memory for peripheral details was positively correlated with choosing on the identification task but negatively correlated with identification accuracy.     

Realism and eyewitness identification research

The importance of realism in eyewitness identification research is examined as the basis for both the credibility and utility of the information it provides. Without knowledge of how laboratory eyewitnesses behave differently from real eyewitnesses, the relevance and external validity of identification studies may be questioned. Factors differentiating these identification contexts are discussed. Witnesses in identification studies are in social decision-making contexts similar to those of real eyewitnesses when their decision to choose someone or to reject the lineup may have a significant impact on others' lives. Two studies are reported which preserve aspects of realism. Both presented witnesses with a realistic vandalism. The second maintained realism through the identification situation. The first study demonstrated effects of biased instructions on witnesses' willingness to make a lineup choice and on identification errors (with the offender present and absent). The second study showed an unexpected preference of witnesses for making an identification when the supposed consequences for the suspect were to be severe. To evaluate the generalizability and utility of laboratory studies it is important to determine whether their results and related theoretical analyses survive the transposition to more realistic contexts. Realistic studies should serve as benchmarks against which simulations are compared and their generalizability evaluated.     

Psychological factors in eyewitness identifications

It has been suggested that incorrect eyewitness identifications have led to more miscarriages of justice than all other factors combined. Several issues which are likely to affect the accuracy of eyewitness identifications are discussed. Research on the impact of race on identifications has illustrated an “own-race bias” in identification accuracy, but it is not yet clear to what extent this bias is related to racial prejudice or amount of cross-racial experience. Although the U.S. Supreme Court has suggested that eyewitnesses who are more certain of their identifications are more likely to be correct, research on this issue has yielded mixed results. Because of its fallible nature, some writers have argued that eyewitness evidence should be used sparingly or not at all in the judicial process. Other suggestions highlight procedures for minimizing bias and providing legal safeguards for the suspect during the identification process, or educating jurors about the potential fallibility of eyewitness evidence by means of judge's cautionary jury instructions or by the use of researchers as expert witnesses. Controversial issues concerning researchers as expert witnesses are discussed.     

Juror sensitivity to eyewitness identification evidence

A mock-jury study was conducted to examine juror sensitivity to eyewitness identification evidence. Subjects were 129 eligible and experienced jurors from Dane County, Wisconsin, who viewed a videotaped trial that involved an eyewitness identification. Ten factors associated with the crime and the identification (e.g., disguise of the perpetrator, retention interval, confidence of the witness) were manipulated. The results of this mock-jury study were combined with those of a previous study using the same experimental stimuli and procedures, but using undergraduates as subjects. This analysis showed that the confidence of the eyewitness was the most powerful predictor of verdicts (p<.05) and that differences between undergraduates and eligible jurors in their sensitivity to eyewitness evidence were negligible.     

Evaluation and integration of eyewitness reports

This study examined how mock jurors assess eyewitness credibility and integrate these assessments with judgments of probative value in simple, corroborating, contradicting, and facilitating inference structures. Subjects listened to an audiotape of a fictional, theft trial. In Experiment 1, contrary to prior research, amount of detail in the target witness's testimony did not influence perceived credibility. In addition, a normative Bayesian rule poorly described subjects' integration of the evidence. A rule that combinedp(event/guilt)weighted by credibility better described the judgments. Experiment 2 was designed to identify variables that affect credibility, given that amount of detail did not. Perceived credibility of the target witness was affected by the credibility of a second witness, and the nature of the effect depended upon the type of inference structure., The results of Experiment 3 suggest that an additive version of the decision rule describes judgments of guilt better than an averaging version.This article is based upon a doctoral dissertation submitted to Indiana University. I would like to thank my advisor, N. John Castellan, Jr., and the other committee members: Igor Gavanski, Margaret J. Intons-Peterson, and Steven J. Sherman. I also wish to thank Janet Magnuson for serving as legal advisor; Kelvin Bartel, Todd Dukes, Justin English, Katherine Harmening, Diana Heise, Nancy Lightfoot, Brigette Oliver, Chris, Reintz, Doug Smith, and Julie York for helping to prepare audiotapes; Tamara Levinson and Sandra Vitous for helping with data collection; and two anonymous reviewers for providing useful comments on an earlier version of this paper.     

Change blindness can cause mistaken eyewitness identification

The current study investigated the effects of change blindness and crime severity on eyewitness identification accuracy. This research, involving 717 subjects, examined change blindness during a simulated criminal act and its effects on subjects' accuracy for identifying the perpetrator in a photospread. Subjects who viewed videos designed to induce change blindness were more likely to falsely identify the innocent actor relative to those who viewed control videos. Crime severity did not influence detection of change; however, it did have an effect on eyewitness accuracy. Subjects who viewed a more severe crime ($500 theft) made fewer errors in perpetrator identification than those who viewed a less severe crime ($5 theft). This research has theoretical implications for our understanding of change blindness and practical implications for the real‐world problem of faulty eyewitness testimony.     

Uses and abuses of eyewitness identification confidence

When attempting to identify an offender whom they saw commit a crime, eyewitnesses are frequently asked to indicate their confidence in their memories. Confidence judgments may be expressed prior to seeing a line‐up, after making an identification decision or in the courtroom. Such judgments can exert an important influence on decision making within the criminal justice system. Here, I examine theory and evidence that bear on the likely usefulness of such confidence judgments for diagnosing the accuracy of the associated identification. Contrary to often expressed views, I argue that confidence recorded immediately after the identification test is informative about the identity of the offender. Confidence expressions obtained at other times are likely to be misleading. Important directions for future confidence research are identified.     

Effects of inconsistent eyewitness statements on mock-jurors' evaluations of the eyewitness,perceptions of defendant culpability and verdicts

In attempting to discredit an eyewitness, it is a common strategy for an attorney to highlight inconsistencies in the eyewitness's recall testimony during cross-examination and encourage the jurors to infer, based on those inconsistencies, that the eyewitness's memory is faulty. An experiment was conducted to examine the effectiveness of this cross-examination strategy. Subjects viewed a simulated cross-examination and rendered judgmenets about the eyewitness and defendant. The type of inconsistent testimony was manipulated between subjects. Subjects exposed to inconsistent recall testimony about either central or peripheral details perceived the eyewitness as less credible (as evidenced by ratings on multiple dimensions) and the defendant as less culpable. Inconsistency on central details led to fewer convictions. Results point to the effectiveness of this cross-examination strategh.     

Juror decision making in eyewitness identification cases

The lay-person's knowledge of the factors that influence eyewitness memory was examined by evaluating the manner in which mock jurors integrated eyewitness evidence to draw inferences about defendant culpability and the likelihood that an identification was correct. Three hundred and twenty-one undergraduates viewed a videotaped trial within which ten witness and identification factors were manipulated between trials. Manipulation checks showed that subjects demonstrated superior memory for the evidence and the manipulated variables had their intended impact on appropriate rating scales. However, only one variable, witness confidence, had reliable effects on subjects' perceptions of culpability, on the perceived likelihood that the identification was correct, and on several other relevant dependent variables. Eight variables that have been shown to affect identification accuracy in the empirical literature had trivial effects on mock jurors' inferences. It was concluded that lay-people are insensitive to the factors that influence eyewitness memory.     

Co-witnesses talk: A survey of eyewitness discussion

Abstract

The objective of this study was to obtain a quantitative measure of the discussion behaviour of real eyewitnesses. Undergraduate psychology students were given a questionnaire to determine if they had witnessed a serious event. Results from the questionnaire showed that the majority of respondents had witnessed a serious event at some point in their lives, and the majority of witnesses were not alone when they observed the event. Respondents who had experienced a serious event for which there was more than one witness present were invited to fill out a follow-up questionnaire. The follow-up study showed that when there is a co-witness present, most people (86%) report discussing the event with the co-witness. This is potentially problematic if the witnesses are contaminating one another's memories of the event. The results are discussed in terms of psychological research and policy implications.     

Accuracy of eyewitness identifications in showups and lineups

Experiment 1 tested one-person and six-person photographic lineup identifications in field situations either immediately, or 30 minutes, or 2 hours, or 24 hours after a 15-second ordinary encounter with a target. Accuracy of performance was superior in six-person lineups than in showups over time. False identifications of a lookalike innocent suspect were significantly greater in showups than in six-person lineups, especially when the suspect wore the same clothing as the culprit. Experiment 2 followed the same research design as Experiment 1, except that only live showup identifications were tested and, in addition, a physically dissimilar innocent suspect was shown to witnesses. The dissimilar innocent suspect was consistently and correctly rejected in the target-absent showup. Hit rates for live suspects were relatively low over the 24-h retention interval. Correct rejections significantly exceeded false identifications only on the immediate test. The lookalike innocent suspect was readily rejected when different clothing was worn at the test. No significant differences were found in hit scores or in confidence-accuracy scores between live and photographic targets. Confidence-accuracy correlations were significant but low across experimental conditions.