Children's eyewitness identification performance: Effects of a Not Sure response option and accuracy motivation

Purpose. Children who witness crimes are sometimes asked to view a photospread lineup to see if they can identify the culprit. Here, we examined the effectiveness of two manipulations designed to assist in overcoming the tendency of child eyewitnesses to choose from lineups, a tendency that manifests in false identifications from target‐absent lineups. Methods. Children aged around 12 years (N = 432) were randomly assigned to control, Not Sure, or accuracy motivation conditions in order to examine both target‐absent and ‐present identification test performance across multiple sets of stimulus materials. Results. The Not Sure option did not affect false alarms or hit rates, but the combination of accuracy motivating conditions and the Not Sure option reduced guessing, with overall rates of false identifications falling by 12.2%. The latter effect was much stronger under some stimulus conditions but not detectable under others, indicating that the manipulations could improve but not impair performance. While there were beneficial effects at the group level, the manipulation did not produce a general change in individual children's decision strategies. Conclusions. Eyewitness identification test manipulations that reliably reduce false alarms, without lowering hits, by child witnesses have not yet been identified. Here, we showed how a simple‐to‐implement accuracy motivation manipulation reduces false alarms under some conditions, while also highlighting the importance of evaluating the efficacy of interventions across varied encoding and test conditions. However, developing a procedure that can produce a generalized improvement in decision making at the individual level remains a major challenge for eyewitness researchers.     

The effect of authority and social influence on eyewitness suggestibility and person recognition

This study investigated the influence of an authority figure on eyewitness identification. Participants watched a staged crime and then were administered a photo lineup by either an authority (policeman) or non-authority figure (civilian). Participants in the authority condition were more likely to choose a lineup member than those in the non-authority condition. There was no effect of authority, however, on the accuracy of the identification decisions. The lack of a deleterious effect suggests that the presence of a police officer during identification procedures does not create an unduly suggestive situation or have undesirable effects on eyewitness identification decisions. Although witnesses' choosing behaviors did not increase the rate of identification errors, the effect of the administrator's authority on choosing was reduced when unbiased instructions (vs. biased instructions) were presented to the witnesses. Thus, support was found for the use of neutral instructions during eyewitness identification procedures.     

Effect of photoarray exposure duration on eyewitness identification accuracy and processing strategy

In this study all offenders admitted to Icelandic prisons over a one year period were approached and 229 (95%) agreed to co-operate with the study. Twenty-seven (12%) of the 229 subjects claimed to have in the past made a false confession during police interviewing. Women prisoners more commonly claimed to have made a false confession than males. The main motives given for having made the false confession were to protect somebody else (48%) and police pressure or escape from custody (52%). The great majority (78%) of the subjects had never retracted the confession, claiming that they had perceived no point in dong so. Twenty-one (78%) of the subjects were convicted of the offenses to which they had, allegedly, made a false confession. The findings in the present study raise the possibility that within an inquisitorial system false confessions may go relatively undetected by the judiciary and be rarely retracted or disputed.     

A field evaluation of the VIPER system: a new technique for eliciting eyewitness identification evidence

Abstract

The main aim of the study was to investigate the rate of claimed false confession during police questioning and identify variables that best discriminate between false confessors and non-false confessors. The participants were 24 627 high school students in seven countries in Europe. Out of 2726 who had been interrogated by the police as a suspect, 375 (13.8%) claimed to have made false confessions to the police. Logistic regression analyses showed that for both boys and girls, having attended substance abuse therapy, been attacked and bullied, and having committed a burglary, significantly discriminated between the false confessor and non-false confessor. In addition for boys, having been sexually abused by an adult outside the family was the single best predictor. The study shows the importance of history of victimization and substance misuse among adolescents in relation to giving a false confession to police during interrogation.     

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.     

Influence of confidence inflation and explanations for changes in confidence on evaluations of eyewitness identification accuracy

Guidelines for conducting police line‐ups typically recommend immediate assessment of eyewitness confidence following identification. This confidence level can presumably be used to estimate accuracy even in the presence of subsequently inflated confidence. In this experiment, we examined students' perceptions of immediate and inflated confidence and whether their reliance on confidence varies as a function of the explanations given by the eyewitness for her inflated confidence. Each of 126 university students viewed one of five versions of a videotaped officer–eyewitness interaction depicting an eyewitness identification and follow‐up interview in which the eyewitness gave a (1) high or (2) moderate level of confidence or inflated her confidence and gave a (3) confidence epiphany, (4) memory contamination, or (5) no explanation for the inflation. The memory contamination and confidence epiphany explanations led to lower ratings of identification accuracy as compared to the high‐confidence control condition, supporting the immediate confidence recommendation but in some ways contradicting previous research on this issue. The results suggest the need for further research to understand the conditions under which confidence inflation influences juror evaluations of eyewitness identification.     

The effect of line‐up administrator blindness on the recording of eyewitness identification decisions

Purpose. Line‐up administrators’ expectations have been shown to influence eyewitnesses’ identification decisions. Expectations may also influence administrators’ willingness to record witnesses’ decisions as positive identifications. Methods. Single‐ and double‐blind participant administrators presented a line‐up to a confederate witness, who identified either the suspect or a filler. Results. A hierarchical log‐linear analysis revealed an interaction effect of blindness and witness choice on participants’ recording of the identification: Single‐blind administrators were more likely to record the confederate's choice as a positive identification when the witness chose the suspect (vs. a filler), whereas double‐blind administrators’ records were not influenced by the witness's choice. An interaction between blindness and witness choice also emerged for participant administrators’ witness evaluations. Single‐blind administrators rated confederates who chose a filler as significantly less credible than those who chose a suspect; double‐blind administrators’ ratings were consistent across photo selection. Conclusions. Blindness influenced line‐up administrators’ record of line‐up outcomes. These results add to the growing body of research supporting the use of double‐blind line‐up administration.     

The effectiveness of judicial instructions on eyewitness evidence in sensitizing jurors to suggestive identification procedures captured on video

Journal of Experimental Criminology - One of the legal safeguards designed to educate jurors about eyewitness evidence is judicial instructions. However, their effectiveness in sensitizing jurors...     

Population substructure can significantly affect reliability of a DNA-led process of identification of mass fatality victims

Aiming to evaluate the effects of population substructure on the reliability of a DNA correspondence in the process of human identification, we used the model of "in silico" constructed populations with and without substructure. Effects of population substructure were evaluated at the level of locus heterozygosity, Hardy-Weinberg equilibrium and mini-haplotype distribution. Inbreeding in a subpopulation of 100 individuals through 10 generations did not significantly alter the level of heterozygosity and Hardy-Weinberg equilibrium. However, analysis of mini-haplotype distribution revealed a significant homogenization in separated subpopulations. Average observed mini-haplotype frequency (f(o)) increased to threefold from expected values (f(e)), and the number of mini-haplotypes with f(o)/f(e) above 10 increased over sixfold, suggesting that the effects of population substructure on calculated likelihood ratios (LR) might be larger than previously estimated. In most criminal cases, this would not represent a problem, whereas for identifications in large-scale mass fatality events, population substructure might considerably increase the risk of false identification.     

The effect of participation in a conversation on recognition and identification of the speakers' voices

Subjects' recognition of their own voice, the voice of a person they had a conversation with, and the voices of two people they heard converse, were compared. They listened to or conversed with each voice for five minutes and then attempted to recognize each voice from among 26 voices saying the same test phrase. In general, subjects recognized the voice of their conversational partner better than the voices of people they had listened to passively. They did not recognize their own voice better than that of their partner. Subjects who recognized their own voice always identified it without error. Although subjects correctly identified other voices they correctly recognized, they also falsely identified voices they falsely recognized. These results are discussed with respect to their practical implications for voice identification by witnesses in legal proceedings and with respect to current theories of memory.     

The influence of processing instructions at encoding and retrieval on face recognition accuracy

Abstract

Current concerns in the U.K. about the management of dangerous severely psychopathically disordered individuals are reviewed in both historical and current contexts. Some reflections are offered on the reluctance on many professionals to engage with individuals showing this disorder.     

gamma-Glutamyltransferase test as a new tool for identification of seminal stains

A simple qualitative method for identification of seminal stains based on a high activity of gamma-glutamyltransferase (gamma-GTP) in human semen is described. It employs the release of alpha-naphthylamine from N-gamma-glutamyl-alpha-naphthylamide by the gamma-GTP action: alpha-naphthylamine couples with Fast Garnet GBC salt to produce a strong brownish-red color. The data on its simplicity, specificity, and stability show that the present method is suitable for medicolegal examination of seminal stains as a preliminary test.     

Testosterone reactivity and identification with a perpetrator or a victim in a story are associated with attraction to violence-related cues

Background

Recent field research has demonstrated that an attraction to aggressive behavior and cruelty is common among combatants and perpetrators involved in organized violence. The biological basis of this appetitive perception of aggression in humans has to date not been studied.

Aims

We examined testosterone as a potential hormonal moderator during induction of specifically appetitive aggressive behavior in the laboratory.

Method

To activate physiological responding related to appetitive aggression, 145 university students (72 women) listened to tape recordings of variants of a violent story. The perspective of the listener in the story was randomized between subjects. Participants were required to either identify as perpetrator, neutral observer, or victim. We assessed changes in saliva testosterone in response to the story. Subsequently, a series of pictorial stimuli (IAPS) with different valence ratings was presented and participants determined the length of viewing time with a button click. This viewing time for negative IAPS was assessed as a dependent variable indicating level of interest in violent scenes.

Results

Men identified themselves with the perpetrator more than women irrespective of the particular perspective presented by the story. Men who responded with an increase in saliva testosterone when adopting the perpetrator perspective chose to view the negative IAPS pictures for longer intervals than participants in other conditions or those who did not exhibit a release in testosterone.

Conclusions

Testosterone moderates attraction to cruel and violent cues in men, as indicated by extended deliberate viewing of violence cues.     

Zinc test as a new tool for identification of human seminal stains

An extremely simple qualitative method for identification of seminal stains based on high levels of zinc in human semen is described. It uses reaction of 1-(2-pyridylazo)-2-naphthol with zinc to develop a deep red color. The data are presented on the sensitivity, stability and specificity of the present method. We can recommend it for identification of human semen especially in old or denatured samples.     

The physical competence test of the Dutch National Police: The effects of wearing a police uniform on test performance

ABSTRACT

In this study, we investigated the effects of wearing a police uniform and gear on officers’ performance during the Physical Competence Test (PCT) of the Dutch National Police. In a counterbalanced within-subjects design, twenty-seven police officers performed the PCT twice, once wearing sportswear and once wearing a police uniform. The results showed clear indications that wearing a police uniform influenced the performance on the PCT. Participants were on average 14 seconds slower in a police uniform than in sportswear. Furthermore, performing the test in uniform was accompanied by higher RPE-scores and total physiological load. It seems that wearing a police uniform during the test diminishes the discrepancy between physical fitness needed to pass the simulated police tasks in the PCT and the job-specific physical fitness that is required during daily police work. This suggests that wearing a police uniform during the test will increase the representativeness of the testing environment for the work field.     

医疗对个人识别和亲子鉴定的影响

个人识别和亲子鉴定是法医鉴定的重要内容,为刑事侦查确定死者的身源和查找认定犯罪嫌疑人提供科学证据;为意外事故遇难者的遗体识别提供科学依据;为父母与子女的血缘关系确认提供科学依据.但是,人体在患了疾病或受伤后,经各种医学方法治疗使其恢复健康过程中,必然要不同程度地引起原有的人体形态、物质成分和运动习惯等的特征改变 ,这就会影响到个人识别和亲子鉴定.因而在鉴定中应引起高度重视.