Target Absent Research Articles

Eyewitness identifications based on biased or unbiased line‐up instructions after a realistic and violent hostage simulation

AbstractFew earlier studies have investigated the effects of highly stressful, realistic, violent, and threatening scenarios on eyewitness identification accuracy in an ecologically valid setting. The majority of studies have relied on laboratory‐based simulated (videos/images) experiments. The present study investigated line‐up accuracy approximately 1 week after a hostage simulation event. We administered biased line‐up instructions to 50% of participants to investigate how this impacted choosing behaviour and accuracy. Based on 1030 line‐up decisions (N = 122), we found that average accuracy was 38% in target present (TP) and 54% in target absent (TA) line‐ups and that biased line‐up instructions decreased overall accuracy (vs. unbiased). The hit rate for TP line‐ups with biased instructions was 0.43 (unbiased instructions: 0.33), while the false alarm rate for TA line‐ups with biased instructions was 0.60 (unbiased instructions: 0.32). We found that high confidence was associated with correct identifications and that shorter response times were indicative of correct rejections. Our findings demonstrate, in a more realistic scenario than the majority of eyewitness identification studies, the effect that biased line‐up instructions lead to increased choosing and decreased accuracy.

The masked villain: the effects of facial masking, distance, lighting, and eyewitness age on eyewitness identification accuracy

ABSTRACT Distance, lighting, and facial masking negatively impact eyewitness identification accuracy. We investigated their combined effect on accuracy and how internal (e.g., eyes) versus external (e.g., hair) masking impacts accuracy. Using live targets witnessed by 1325 participants, we investigated the effects of distance (5m, 12.5m, 20m), lighting (optimal:300lx, suboptimal:2lx), facial masking (no facial masking, sunglasses, hood, sunglasses & hood), and eyewitness age (5-90) on identification accuracy in target-present (TP) or target-absent (TA) eight-person simultaneous photograph line-ups. TP identification accuracy, with no facial masking, for all participants was .69 (.96 for only 18-44-year-old choosers) at 5m, .34 (.58) at 12.5m, and .17 (.42) at 20m. TA rejection accuracy for all participants was .63 (.60 for only 18-44-year-olds) at 5m, .42 (.54) at 12.5m, and .46 (.46) at 20m. Facial masking further decreased accuracy; internal facial masking had the strongest negative effect. The combined negative effects of distance, lighting, and facial masking resulted in chance-level performance in TP line-ups (i.e., .125) in some instances. We also found a positive association between accuracy and high confidence and shorter response times. We recommend that law enforcement agencies and researchers report these variables to allow for the postdiction of the likely accuracy of an eyewitness decision.

0058 The sleepy eyewitness: Self-reported sleep predicts eyewitness memory

Abstract Introduction Sleep is critical for memory, but research indicates that eyewitness identification may be an exception. We conducted three experiments to assess the effect of self-reported sleep duration and quality, and current sleepiness on eyewitness recall for a mock crime and suspect identification. Experiments 1 and 2 looked at pre-encoding sleep on lineups and showups, respectively. Experiment 3 investigated lineups across two days to assess retrieval effects. Methods Participants viewed a mock crime video then answered sleep questions as well as central and peripheral recall questions over the crime. Participants were then randomly assigned to view a fair 6-person target-present (TP) or target-absent (TA) lineup for experiments 1 and 3, or a TP or TA showup for experiment 2. In experiment 3, the recall questions and lineups occurred on day 2, but the sleep questions were asked both days. Decision confidence was provided after the identification procedure. Results Sleep quality predicted central recall for experiment 1 [F(1, 3834)=12.96, p<.001] whereas sleep quantity predicted central recall for experiment 2, F(1, 2712)=36.22, p< .001. Choosing rate for pre-encoding sleep was higher for low quality [X2(1)=29.10, p<.001] and low duration [X2(1)=20.15, p<.001], but false IDs were lower for high duration [X2(1)=29.76, p<.001] and high quality, X2(1)=35.47, p<.001. High quality self-reported sleep increased discriminability for lineups, G=2.14, p=.016. False IDs for showups were lower for high duration [X2(1)=5.27, p=.024] and all three sleep questions predicted discriminability for showups: more sleep (G=2.85, p=.002), better sleep (G=2.60, p=.005), and less sleepiness, G=2.44, p=.007. Showups had greater accuracy (p=.038) and a stronger confidence-accuracy relationship (p<.001) for the average of the “good sleep” conditions than the average of the three “bad sleep” conditions, p=.022. In experiment 3, involving post-encoding self-reported sleep, there were still effects on recall but minimal effects on eyewitness identification (and no effects on discriminability). Conclusion Self-reported sleep for the night prior to the crime could be an important individual difference variable for eyewitness memory, affecting encoding more than post-encoding processes. Support (if any) This project was supported by Grant 2018-R2-CX-0027 awarded by the National Institute of Justice, Office of Justice Programs, and U.S. Department of Justice.

The role of experimenter familiarity in children’s eyewitness identification

Child eyewitnesses show a high false identification rate on target-absent (TA) lineups despite good performance on target-present (TP) lineups. One explanation is that children feel a social pressure to choose when presented with a TA lineup. We investigated whether experimenter familiarity would reduce social pressure and improve accuracy on TA lineups. Children (5–7 years, N = 120) watched a short video of a staged theft; 1–2 days later they completed a TP or TA lineup with a familiar or unfamiliar experimenter. Experimenter familiarity had an impact on lineup response in TA lineups only, with more correct ‘not there’ and fewer ‘not sure’ responses when the children were familiar with the experimenter. The results provide further evidence to support the social aspect of eyewitness identification decisions in children and provide a possible strategy to improve identification accuracy for those working with children in the criminal justice system.

Validity of mock-witness measures for assessing lineup fairness

ABSTRACT Although eyewitness researchers have used mock-witness measures to assess aspects of lineup fairness, they have paid little attention to their validity. The current study tested predictive validity, convergent validity, and discriminant validity of mock-witness measures from a meta-analytic perspective. Overall, mock-witness measures had predictive validity, particularly in target-absent (TA) lineups – the lineup fairness estimated by the measures reliably predicted eyewitnesses’ choosing behaviors and discriminability of a suspect from fillers in TA lineups. However, correlations between lineup fairness estimated by mock-witnesses and eyewitness performance were significant in target-present (TP) lineups only when eyewitnesses had a moderate memory for the perpetrator. Multitrait-multimethod correlations demonstrated significant intradomain correlations between mock-witness measures and other lineup fairness indices and nonsignificant interdomain correlations between the mock-witness measures and indices reflecting memory strength for the perpetrator, which supported convergent validity and discriminant validity, respectively. The implications for research and practice are discussed.

Eyewitness identifications after witnessing threatening and non-threatening scenes in 360-degree virtual reality (or 2D) from first and third person perspectives.

In eyewitness research the frequent use of video playback presented on a computer screen (i.e., 2D videos) in laboratory-based research is problematic due to the low realism of this method when presenting, for example, threatening (and non-threatening) first-person (and third-person) scenarios. However, in contrast to 2D videos, 360-degree videos presented in virtual reality (VR) presents the opportunity of achieving more realistic and immersive scenarios that might be better suited to mimic real-life incidents, as for example, in the case of a threatening first-person robbery. In the present study, we asked 37 participants to watch eight pre-recorded threatening or non-threatening 2D and VR videos, viewed from either a first- or third-person perspective. After each video, participants assessed the observed target’s appearance and were then presented with either a target present (TP) or target absent (TA) six-person photograph line-up. We expected that VR would result in higher degrees of accuracy in both TP and TA line-ups compared with 2D and that the differences between manipulations would be more pronounced within VR compared with 2D. We found that TP (but not TA) accuracy was higher in 2D compared with VR videos (91 vs. 66%), that there was no main effect of perspective, and that threatening scenes increased TP (but not TA) accuracy compared to non-threatening scenes (86 vs. 70%). Furthermore, in VR (but not in 2D), threatening scenes increased TP (but not TA) accuracy compared with non-threatening scenes (85 vs. 40%). The results go against the expected increased accuracy in VR (vs. 2D) videos but support the notion that threatening (vs. non-threatening) scenes can increase identification accuracy in VR but not necessarily in 2D.

The number of fillers may not matter as long as they all match the description: The effect of simultaneous lineup size on eyewitness identification

SummaryAccording to the Diagnostic Feature‐Detection (DFD) hypothesis, the presence of fillers that match the eyewitness's description of the perpetrator will boost discriminability beyond a showup, and very few fillers may suffice to produce the advantage. We tested this hypothesis by comparing showups with simultaneous lineups of size 3, 6, 9, and 12. Participants (N = 10,433) were randomly assigned to one of these conditions, as well as target‐present (TP) versus target‐absent (TA) lineup. As predicted by the DFD hypothesis, lineups were superior to showups, and there was no advantage with increased lineup size beyond a 3‐member lineup. The confidence‐accuracy (CA) relationship held a similar pattern. The only effect of increased lineup size was a lower likelihood of choosing a suspect (guilty or innocent). We conclude that police should focus more on the quality rather than quantity of fillers.

The Mystery Man Can Increase the Reliability of Eyewitness Identifications for Older Adult Witnesses

Some groups of eyewitnesses, such as older adults and children, are less likely to correctly reject a target-absent (TA) line-up, as compared to younger adults. Previous research reports that using a silhouette in a video line-up called the ‘mystery man’ could increase correct rejections for TA lineups for child eyewitnesses, without reducing correct identifications for target-present (TP) line-ups (Havard and Memon in Appl Cogn Psychol 27:50–59, 2013). The current study, using older and younger adults, investigated whether using the mystery man would also increase the identification accuracy for older adults, without impairing younger adults’ identification accuracy. The results found that older adults in the ‘mystery man’ condition rejected TA line-ups significantly more often than those in the control condition (52 vs. 24 %), with no significant effect upon the TP line-ups. For the younger adults, the mystery man had no influence on identification responses for the TA or TP line-ups. Our findings suggest the mystery man technique may be beneficial for older adults, without detrimentally affecting the accuracy for younger adults, and thus could increase the reliability of eyewitness evidence, where video line-ups are employed.

The effect of choice reversals on blindness for identification decisions

ABSTRACTThe present study examined blindness for identification decisions from target-present (TP) and target-absent (TA) lineups using a field study methodology. Eighty pedestrians were exposed to a staged theft. Subsequently, they were asked to identify the thief and the victim from separate, simultaneous six-person lineups. Their identification decision concerning the thief lineup was manipulated such that participants’ selections were exchanged with a previously unidentified lineup member (choice exchange) and lineup rejections were turned into identifications (choice reversal). Participants were 7–10 times less likely to detect choice exchanges (66.7%) compared with choice reversals (11.2%). Furthermore, identification accuracy was not a prerequisite for detection. Thus, rejections and particularly selections made from both TP and TA lineups are susceptible to choice blindness. Finally, our study implies that for blindness in eyewitness identification decisions between-category changes (i.e. choice reversals) are easier to detect than within-category changes (i.e. choice exchanges).

Own-age bias in video lineups: a comparison between children and adults

The present study investigated whether child (six–eight years of age) and adult witnesses (18–29 years of age) would exhibit an own-age bias when trying to identify targets from video lineups. One hundred and eighty-six participants viewed two filmed events that were identical, except one starred a child target and one a young adult. After a delay of two–three days each witness saw a lineup for the child and adult target. Children exhibited an own-age bias and were better at correctly identifying the own-age target from a target-present (TP) lineup and made more correct rejections for the own-age target-absent (TA) lineup. Adults however, showed a reversed own-age bias for the TP lineups as they made more correct identifications for the child target, but exhibited no bias for the TA lineups. The results suggest that differences in identification accuracy may be due to whether witness age and suspect age overlap.

The Mystery Man Can Help Reduce False Identification for Child Witnesses: Evidence from Video Line‐ups

SummaryIt is well established that children (as young as 5 years) can correctly identify a target from a target present (TP) line‐up as accurately as adults; however, when shown a target absent (TA) line‐up, children make more false identifications. In the present study, children aged 5–7 and 8–11 years viewed a film of a staged theft, then 1–2 days later were shown either a TP or TA video line‐up. Half of the witnesses viewed line‐ups that included a ‘mystery man’ (a black silhouette with a white question mark), which they could select if they did not recognise anyone from the line‐up. When the ‘mystery man’ was present in the line‐up, there were significantly fewer false identifications for the TA line‐ups. This study shows that including a silhouette in a video line‐up can help reduce false identifications for children as young as 5 years of age, without reducing correct identifications. Copyright © 2012 John Wiley & Sons, Ltd.

Co‐witness information influences whether a witness is likely to choose from a lineup

Purpose. Much crime is witnessed by more than one eyewitness, and witnesses may learn information about other witness's decisions throughout the identification and trial process. The objective of this paper was to investigate whether hearing about a co‐witness's type of lineup decision and subsequent confidence level affects another witness's type of lineup choice.Methods. A total of 304 undergraduate students watched a crime video with a confederate co‐witness. After the video, the witnesses completed an identification task. Prior to completing the task, the participant learned that the confederate co‐witness either chose from or rejected the lineup and was subsequently confident or not confident in that decision (or heard no co‐witness information). Participants completed the identification task using either a target present (TP) or target absent (TA) lineup.Results. Overall, those who heard the co‐witness chose from the lineup were more likely to choose from the lineup than those who heard no co‐witness information or who heard the co‐witness rejected the lineup. In addition, witnesses who chose from the lineup and heard the co‐witness chose from or rejected the lineup expressed more confidence in that choice if the co‐witness was more confident versus if the co‐witness was less confident.Conclusions. In cases of multiple witnesses, identification decisions may not be independent pieces of evidence. Therefore, it is important that police separate co‐witnesses throughout the identification process.

Delay and Age Effects on Identification Accuracy and Confidence: An Investigation Using a Video Identification Parade

SummaryA total of 236 children (7–8‐year‐olds and 13–14‐year‐olds) attempted identification from either target‐present (TP) or target‐absent (TA) video parades, after either two days or two weeks, following exposure to a live target. It was found that with TP line‐ups, the most frequent response was a correct identification, but in the TA condition, the most frequent response was a false identification. Under both TP and TA conditions, the 3‐way interaction of delay, age and response was significant. Further analysis revealed that delay was the major contributor of variance, causing an increase in errors for both age groups in TP delayed line‐ups but only for the younger age group in TA delayed line‐ups. Confidence varied as a function of type of identification response made, with the highest confidence being given to a correct identification in a TP line‐up. However, response confidence entered into a number of interactions involving both delay and age. Copyright © 2011 John Wiley & Sons, Ltd.

A comparison of video and static photo lineups with child and adolescent witnesses

AbstractIn the UK video parades are the preferred method of identification employed in criminal cases. This policy implementation has been employed with little or no evidence concerning its validity. The reported research examines the effect of new video technology on children's identification evidence. The study compared 7–9 and 13–15‐year olds' ability to make identifications from either video or static photo lineups. Two hundred and fifteen participants witnessed a live event and then after a delay of 2–3 days viewed a target present (TP), or target absent (TA) video or photo lineup. For video and photo TP lineups, correct responses did not differ as a function of age. Video lineups produced lower rates of false identifications for the TA lineups, but only for adolescent witnesses. It is concluded that there is nothing contra‐indicated in the use of video identification procedures with children, and possibly certain benefits can accrue from its use. Copyright © 2009 John Wiley & Sons, Ltd.

Novel lineup methods for improving the performance of older eyewitnesses

AbstractPrevious research shows that older witnesses demonstrate poorer lineup performance compared to younger adults. Two experiments are presented which investigated the effectiveness of pre‐identification procedures aimed to reduce false identifications made by older adults. In experiment one older adults' demonstrated poorer lineup performance compared to younger adults. However, older adults benefited from pre‐lineup questions and a practice lineup prior to viewing a target absent (TA) lineup. In a second experiment, participants in the practice lineup condition made significantly fewer false identifications and more correct rejections on two TA lineups compared to participants in the control condition. On both target present (TP) lineups there was no significant difference in lineup performance between the two conditions. The effect of pre‐identification procedure on self‐reported lineup decision strategy and memory for non‐biased lineup instructions are discussed, as well as future research directions. Copyright © 2009 John Wiley & Sons, Ltd.

Are old witnesses always poorer witnesses? Identification accuracy, context reinstatement, own-age bias

Young adults (16–30 years) and old adults (64–86 years) (N=96) viewed a staged videotaped crime event involving a young and old perpetrator. Prior to viewing either target present (TP) or target absent (TA) line-ups, half the participants received context reinstatement photographs. For the young line-up a significant effect of age group was found with old participants demonstrating poorer performance. However, on the old line-up there was no significant effect of age group. Importantly, a significant beneficial effect of context reinstating photographs existed for participants viewing the old TA line-up. An own-age bias did not exist for either age group in terms of accuracy but young participants were significantly more likely to choose a line-up member from the old line-ups compared to the young line-ups. It was concluded that given certain circumstances it may be possible for old adults to perform at an equivalent level to young adults.

Aiding the Performance of Older Eyewitnesses: Enhanced Non-Biased Line-Up Instructions and Line-Up Presentation

The study examined possible methods for improving the performance of older eyewitnesses on identification line-ups. Young and old adults viewed a simulated crime event involving a young and old perpetrator, and were subsequently asked to identify these two perpetrators from line-ups that were either target present (TP) or target absent (TA). Research conducted by the present authors indicates that older adults have significant problems with remembering instructions informing them that the perpetrator may or may not be present in the line-up and this may contribute to the age deficit in line-up performance. Therefore, in the present study, prior to the line-ups, half the participants received enhanced non-biased line-up instructions. Furthermore, the performance age deficit demonstrated by older adults in previous relevant studies is largely characterised by an increase in false identifications. The sequential line-up is known to reduce false identifications. Therefore, half the participants viewed line-ups that were presented sequentially and half viewed line-ups that were presented simultaneously. Older participants were found overall to demonstrate poorer line-up performance compared to younger participants. Though enhanced line-up instructions led to significantly better memory concerning the possibility the perpetrator may or may not be present in the line-up, they had no significant effect on line-up performance. Line-up presentation (sequential vs. simultaneous) had differential effects across conditions, with sequential presentation not always being beneficial.

Non-biased lineup instructions do matter – a problem for older witnesses

From the limited literature on older witnesses’ identification performance it is known that they are less accurate on lineups compared to younger witnesses. What is less certain is why they show this age deficit and what can be done to aid their performance. Witnesses forgot being given non-biased lineup instructions informing witnesses that the perpetrator may or may not be present. More older witnesses than younger witnesses forgot and witnesses who failed to report remembering these instructions were significantly less accurate on the lineups. In addition, the current study investigated the use of sequential lineup presentation and stringent decision criteria to aid the performance of older witnesses. Sequential presentation was beneficial to both younger and older adults when the lineup was target absent (TA) but was detrimental when the lineup was target present (TP). Stringent decision criteria had no significant beneficial effect. Future directions for aiding older witnesses’ performance are discussed.

Aging and lineup performance at long retention intervals: effects of metamemory and context reinstatement.

Young (18-30 years) and older (62-79 years) adults (N = 96) engaged in a 20-min live interaction with the future target in a lineup task. One month later, participants were interviewed about the events in the prior encounter (with or without context reinstatement), and then they saw a target-present (TP) or target-absent (TA) lineup. The lineup was followed by the Benton Face Recognition Test (A. Benton, A. Sivan, K. Hamsher, N. Varney, & O. Spreen, 1994), which correlated positively with accuracy in TP, especially for young adults. False identification in TA was associated with (a) higher scores on a memory self-efficacy scale and (b) higher recall of information about the initial event, although only for seniors. Results suggested that age-related increases in false identification generalize to ecologically valid conditions and that seniors' performance on lineups is negatively related to verbal recall as well as to self-reports of satisfactory experiences with memory in life.