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.     

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.     

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.     

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.     

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.     

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.     

Confidence and accuracy of eyewitness identification from lineups

Recent studies of confidence-accuracy correlations in eyewitness-identification experiments have produced highly variable results (Deffenbacher, 1980; Wells & Murray, 1984) with some correlations near 0 (Malpass & Devine, 1981) and others as high as 0.5 (Brigham et al., 1982). Much of this variability may be accounted for by differences, in the design of the research. Specifically, lineup experiments in which the to-be-identified person (target) is always present tend to produce higher confidence-accuracy correlations than studies also providing blank or target-absent lineups replacing the target with a lookalike. A reanalysis of previously collected data (Lindsay & Wells, 1980; Wallbridge & Lindsay, 1982) revealed that lineup foils (nontargets) were identified with significantly less confidence than targets or lookalikes but that targets and lookalikes were identified with equal confidence. Two experiments were conducted to test the hypothesis that confidence of identification is a function of the similarity of the identified person to the original target. The first experiment using nonstudent subjects (n=53) and multiple targets (n=14) to increase generalizability, demonstrated that the person in the lineup who most closely resembled the target was identified with the highest mean level of confidence. The second experiment examined confidence in identification following a crime staged for 260 introductory psychology students. The results indicated that the similarity of foils to the target (established by independent ratings) was predictive of both the frequency and confidence of identification of faces.     

Reinforced self-affirmation as a method for reducing the eyewitness misinformation effect

The misinformation effect occurs when an eyewitness includes information in their account that is incongruent with the event they witnessed, and stems from being exposed to incorrect external sources. Yet little research has been undertaken on techniques that could protect eyewitnesses from the influence of misinformation, despite the dangerous consequences of distorted testimony. In this article, a method of enhancing self-confidence, called reinforced self-affirmation (RSA), was proven to reduce the misinformation effect in five experiments. First, participants watched or heard an original event take place. They were then exposed to post-event material containing false information about that event, and finally they were given a memory test about the original material. The RSA, which took place either before the post-event material or before the final test, consisted of self-affirmation (recalling the greatest achievements in life) and external positive feedback (simulated ‘good’ results in a memory test or fake favourable results on personality tests). A meta-analysis of all five experiments revealed that the overall effect of RSA on reducing the misinformation was significant (effect size of 0.94), suggesting that this technique has the potential to be developed for practical use to make eyewitnesses less vulnerable to misinformation.     

Gender effects in eyewitness accounts of a violent crime

Abstract

This research examined two aspects of gender effects in eyewitness accounts: whether there are gender differences in memory for a violent crime and how gender of perpetrator/victim affect witnesses' evaluations of perpetrator/victim behavior. Eighty male and 84 female university students saw a film showing a simulated manslaughter with either a male or female perpetrator stabbing a male or female victim. A female advantage was found in overall memory of the crime, and both a male perpetrator and a male victim were assigned more culpability than their female counterparts. It is suggested that females may have more elaborated categories for person information than males, which should facilitate female accuracy in person memory. Alternatively, the present findings may reflect a more general female advantage in episodic memory performance. Stereotype assimilation is suggested to account for the differential evaluations of a male and female perpetrator/victim.     

Influence of expert testimony regarding eyewitness accuracy on jury decisions

To determine the influence of expert testimony regarding the general unreliability of eyewitnesses, a two-phase study was conducted. In the first phase, 24 community residents served as jurors on four six-person juries. A burglary case was tried in 120 District Court. El Paso, Texas. Two juries heard all the evidence including the expert testimony of a psychologist and the other two heard all of the testimony except that of the psychologist. During the second phase, 24 student jurors constituting four six-person juries viewed a videotape of the trial. Two of these juries saw the entire proceeding from the first phase including the expert testimony and the remaining two saw all but the expert testimony. All juries acquitted the defendant; however, those who heard the expert testimony significantly lowered their judgments of the accuracy and reliability of eyewitness identification as well as its overall importance to the trial. Further, those juries that heard the expert testimony spent a significantly longer time discussing eyewitness identification as well as other relevant evidence. No differences between community residents and college student juries were obtained.The authors wish to thank Judge Brunson Moore, Mr. David Jeans, Mr. Ricky Glenn Smith, Detective James Christianson, D. Steven Cooper, Rachel Hanna, Daniel Torres, and Patricia Tetreault. All of these people participated in the trial and without them this research could not have been conducted. This research was supported by Gift Funds of the Department of Psychology, University of Texas at El Paso.     

论分配制度价值定位与农民增收制度优化

分配制度改革是当今中国的一项重大社会变革,这场变革不仅关系到整个社会经济的协调和运行,还会对每一个人的生活产生重要影响。基于农民增收的现实需求,我国的分配制度改革必须合理协调公平与效率的关系,在初次分配中须将激发市场效率作为制度设计的基本主题,而在再次分配中则须注重政府对社会公平的适当矫正。     

Effects of expert psychological advice on human performance in judging the validity of eyewitness testimony

A review is made of recent experimental research regarding how well human observers can judge the accuracy of eyewitness testimony. It is concluded that people: (a) may be overwilling to believe in the accuracy of eyewitnesses' memory; (b) rely too heavily on the confidence of eyewitnesses in judging the validity of testimony; (c) fail to adequately account for witnessing conditions across crimes; and (d) cannot discriminate between accurate and inaccurate witnesses within crimes. New data are reported from an experiment designed to test the effects that expert psychological advice has on subject-jurors' performance with regard to these four deficiencies. The results showed that expert advice served to eliminate the overbelief bias and greatly reduced subject-jurors' reliance on the confidence of the witnesses. Expert, advice did not improve the extent to which subject-jurors took account of the witnessing conditions across crimes nor their ability to discriminate between accurate and inaccurate witnesses within crimes.     

Impacts of increasing volume of digital forensic data: A survey and future research challenges

A major challenge to digital forensic analysis is the ongoing growth in the volume of data seized and presented for analysis. This is a result of the continuing development of storage technology, including increased storage capacity in consumer devices and cloud storage services, and an increase in the number of devices seized per case. Consequently, this has led to increasing backlogs of evidence awaiting analysis, often many months to years, affecting even the largest digital forensic laboratories. Over the preceding years, there has been a variety of research undertaken in relation to the volume challenge. Solutions posed range from data mining, data reduction, increased processing power, distributed processing, artificial intelligence, and other innovative methods. This paper surveys the published research and the proposed solutions. It is concluded that there remains a need for further research with a focus on real world applicability of a method or methods to address the digital forensic data volume challenge.