Non‐blind lineup administration biases administrators' interpretations of ambiguous witness statements and their perceptions of the witness

Administering lineups “blind”—whereby the administrator does not know the identity of the suspect—is considered part of best practices for lineups. The current study tests whether non‐blind lineup administrators would evaluate ambiguous eyewitness statements, and the witness himself or herself, in a manner consistent with their beliefs. College students (n = 219) were told the identity of the suspect or not before administering a lineup to a confederate‐witness who made an ambiguous response (e.g., “it could be #3 but I'm not sure”). When ambiguous witness statements matched administrators' beliefs regarding the suspect (compared with when they mismatched administrators' beliefs, or administrators had no belief), administrators (a) were significantly more likely to record the statement as an identification (as opposed to a “not sure” response); (b) were significantly less likely to make statements that might lead the witness away from the suspect; and (c) evaluated the witness's viewing conditions significantly more positively.     

Identification accuracy of a single culprit in a multiple-perpetrator mock crime

IntroductionEyewitness identification research has mainly examined the identification accuracy of a single perpetrator but many actual crimes involve not one but several perpetrators.ObjectiveThe aim of the study was to examine the identification accuracy if only one lineup for one of the two perpetrators is presented in a multiple perpetrator crime.MethodThe sample consisted of 180 participants who saw a theft video followed by distraction tasks. One group of participants saw lineups for both of the perpetrators (one target present and one target-absent) whereas the other saw only a single lineup (either target-present or target-absent) for one of the two perpetrators.ResultsParticipants who saw a single lineup did not make more inaccurate identification decisions then participants who saw two lineups. Decision accuracy in the first lineup was not associated with the decision accuracy in the second lineup.ConclusionThe results are discussed in terms of the number of perpetrators and line-up presentation types.     

Configural and component processing in simultaneous and sequential lineup procedures

Configural processing supports accurate face recognition, yet it has never been examined within the context of criminal identification lineups. We tested, using the inversion paradigm, the role of configural processing in lineups. Recent research has found that face discrimination accuracy in lineups is better in a simultaneous compared to a sequential lineup procedure. Therefore, we compared configural processing in simultaneous and sequential lineups to examine whether there are differences. We had participants view a crime video, and then they attempted to identify the perpetrator from a simultaneous or sequential lineup. The test faces were presented either upright or inverted, as previous research has shown that inverting test faces disrupts configural processing. The size of the inversion effect for faces was the same across lineup procedures, indicating that configural processing underlies face recognition in both procedures. Discrimination accuracy was comparable across lineup procedures in both the upright and inversion condition. Theoretical implications of the results are discussed.     

Evidence of differential performance on simultaneous and sequential lineups for individuals with autism-spectrum traits

Given the impaired facial recognition of autistic individuals, we examined whether certain autism-spectrum traits affected eyewitness identification performance in a general adult population. In a sample of 120 individuals, levels of autism-spectrum traits were examined in relation to performance on simultaneous vs. sequential lineups using a signal detection paradigm. For simultaneous lineups, total Autism Spectrum Quotient (AQ) scores and scores on the excessive Attention to detail subscale were related to fewer hits and a more conservative response criterion. Attention to detail interacted with lineup type in that it was significantly related to improved discrimination accuracy and a less conservative response criterion in sequential lineups, but with impaired discrimination accuracy and a more conservative response criterion in simultaneous lineups. Higher AQ scores on the Attention switching subscale resulted in fewer hits, lower discrimination accuracy, and a more conservative response criterion with sequential lineups. Additionally, partial disguises led to more false alarms but not decreased accuracy. More thorough investigations of the effect of lineup type on identifications are needed before policy changes are recommended.     

How elevated blood alcohol concentration level and identification format affect eyewitness memory: A field study

Research shows that alcohol has a small and inconsistent effect on eyewitness recall and no effect on witnesses' lineup decisions. Much of this literature has tested participants with low‐to‐moderate blood alcohol concentration (BAC) levels, and no study has directly examined how identification procedure impacts intoxicated witnesses' decisions. In the present study, bar patrons' (N = 132) BAC levels were recorded before participating in a task. Midway through the task, they were interrupted by an intruder. Participants then recalled the incident via a staged interview and attempted to identify the intruder from a target‐present or target‐absent showup or lineup. Although elevated BAC levels (high as 0.24%) reduced the quantity and quality of information provided, BAC had no effect on witnesses' identification decisions regardless of format. Results highlight the importance of testing witness memory across a broad BAC spectrum and provide evidence that alcohol does not affect witnesses' identification ability.     

The Confidence of Eyewitnesses in Their Identifications From Lineups

The confidence that eyewitnesses express in their lineup identifications of criminal suspects has a large impact on criminal proceedings. Many convictions of innocent people can be attributed in large part to confident but mistaken eyewitnesses. Although reasonable correlations between confidence and accuracy can be obtained under certain conditions, confidence is governed by some factors that are unrelated to accuracy. An understanding of these confidence factors helps establish the conditions under which confidence and accuracy are related and leads to important practical recommendations for criminal justice proceedings.     

A position of influence: Variation in offender identification rates by location in a lineup

Researchers have identified several threats to the validity of the use of the lineup as a test of true recognition. One concern is related to the structure of the simultaneous lineup. It is argued here that a simultaneous presentation of an array nonetheless requires the viewer to undertake sequential processing of the items in the array. This sequential pattern is unlikely to be random and therefore the position of a culprit in a lineup may have a significant effect on the accuracy of witness selection. A simulated crime (snatching of a handbag) was shown to a convenience sample of 84 undergraduates aged between 18–23 years. In 84 subsequent live lineups, the offender was placed with four foils. He was positioned on the far left (position 1) in 42 cases (50%), and in 14 cases respectively in positions 3 (centre), 4 (centre right) and 5 (extreme right). A very strong association was found between position and correct identification with position 1 placement leading to a significantly lower proportion of correct identification (7.1%) compared to position 3 (50.0%), position 4 (64.3%), and position 5 (21.4%). Steps to remedy possible positional biases are considered. Copyright © 2009 John Wiley & Sons, Ltd.     

An evaluation of lineup presentation,weapon presence,and a distinctive feature using ROC analysis

We conducted an experiment (N = 2675) including both laboratory and online participants to test hypotheses regarding important system and estimator variables for eyewitness identification. Simultaneous lineups were compared to sequential lineups with the suspect presented early versus late because there is evidence that suspect position could be an important factor determining a simultaneous versus sequential advantage in guilty-innocent suspect discriminability. We also manipulated whether or not the perpetrator held a weapon or had a distinctive feature on his face, to re-evaluate recent evidence that these factors interact. Overall, the simultaneous lineup yielded higher discriminability than the sequential lineup, and there was no effect of sequential position. Discriminability was higher when the perpetrator had no weapon, but only when no distinctive feature was present. We conclude with a discussion of the importance of exploring interactions between system and estimator variables using Receiver Operating Characteristic (ROC) analysis.