Jamal Mansour

• PhD
• Associate Professor at University of Lethbridge

The Cross-Race Effect (CRE) is a reliable and robust phenomenon, whereby individuals better recognize faces that belong to their race compared to another race. Our goal was to produce items for a self-report Inventory (i.e., CRE-I) that brings together known predictors of the CRE to improve the postdiction of cross-race eyewitness accuracy.We expec...

While verbal and numeric confidence may similarly predict identification accuracy, there are many challenges to overcome in the use of verbal confidence, despite the criminal justice system’s preference for it. Eyewitnesses could potentially provide scale ratings after verbal judgments or vice versa, if the confidence-accuracy relationship is maint...

Typically, an eyewitness' verbal confidence is used to judge the reliability of their lineup identification. Across three experiments (N = 3976), we examined eyewitnesses' own words confidence in their lineup decision. For identification decisions (n = 1099), we identified 781 quantitatively unique responses representing 132 qualitatively unique st...

High confidence has been associated with high accuracy under certain conditions. Yet, how researchers operationalize ‘high confidence’ varies across publications and depends on who is asked. In this study, we collected numeric interpretations to determine thresholds for high confidence. Layperson participants provided a minimum, best, and maximum e...

We compared an evidence-based lexicon to numeric and verbal methods for obtaining confidence in a lineup decision. Participants watched two videos (one target each) and, following a delay, made a lineup decision for each target. Confidence was provided after each lineup decision using the lexicon (numeric, verbal, and visual), verbally (own words,...

Eyewitnesses typically communicate identification confidence to law enforcement in their own words. Despite a positive confidence-accuracy relationship when confidence is measured numerically (and identifications uncontaminated), there is no clear basis for determining whether oft-ambiguous verbal phrases indicate low, medium, or high confidence. P...

We developed an evidence-based tool (a lexicon) which comprises verbal and numeric information for gathering and communicating eyewitness confidence. With two studies, we obtained interpretations of frequently used verbal confidence statements made by eyewitnesses that we used to derive the lexicon. We expected that a distinct set of phrases would...

Typically, an eyewitness’ verbal confidence is used to judge the reliability of their lineup identification. Across three experiments (N = 3976), we examined identifiers’ confidence in their lineup decision using their own words (n = 1099). For identification decisions, we identified 781 quantitatively unique responses representing 132 qualitativel...

The current study examined the concurrent and predictive validity of four families of lineup-fairness measures – mock-witness measures, perceptual ratings, face-similarity algorithms, and resultant assessments (assessments based on eyewitness participants’ responses) – with 40 mock crime/lineup sets. A correlation analysis demonstrated weak or non-...

Research on eyewitness identification often involves exposing participants to a simulated crime and later testing memory using a lineup. We conducted a systematic review showing that pre-event instructions, instructions given before event exposure, are rarely reported and those that are reported vary in the extent to which they warn participants ab...

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...

Objective: Prior research indicates disguise negatively affects lineup identifications but the mechanisms by which disguise works have not been explored and different disguises have not been compared. We investigated how two different types of disguise, four levels of varying degrees of coverage, and lineup type influence eyewitnesses' identificat...

When administering sequential lineups, researchers often inform their participants that only their first yes response will count. This instruction differs from the original sequential lineup protocol and from how sequential lineups are conducted in practice. Participants (N = 896) viewed a videotaped mock crime and viewed a simultaneous lineup, a s...

When administering sequential lineups, researchers often inform their participants that only their first yes response will count. This instruction differs from the original sequential lineup protocol and from how sequential lineups are conducted in practice. Participants (N = 896) viewed a videotaped mock crime and viewed a simultaneous lineup, a s...

General Audience Summary Researchers commonly ask participants who view a lineup in an experiment to indicate how confident they are in their decision using a scale (e.g., 0–100%; Not at all confident to Completely confident). However, in practice, eyewitnesses may be asked to make a verbal statement—to give their confidence in their own words or t...

Historically, researchers have collected eyewitness identification confidence using scales; however, in practice, eyewitnesses are more commonly asked for a verbal statement. In Experiment 1, participants viewed a simultaneous lineup and provided confidence in their own words, by explaining why they made their decision or by selecting from statemen...

We argue that perceivers associate collective directional movement – groups moving from one place to the next – with higher levels of social cohesion. Study 1 shows that pairs are rated as being more cohesive when described as engaging in directional movement compared to non‐directional activities. Study 2 replicates this finding using film clips....

We examined the role of exposure duration and scene complexity on the weapon focus effect (WFE). Memory for the a mock crime was affected more by a weapon than an unusual but nonthreatening object. Threat reduced correct identifications when the event was short but not long; duration of the event did not interact with unusualness. Additionally, we...

Eyewitness identification experiments typically involve a single trial: A participant views an event and subsequently makes a lineup decision. As compared to this single-trial paradigm, multiple-trial designs are more efficient, but significantly reduce ecological validity and may affect the strategies that participants use to make lineup decisions...

Triers of fact sometimes consider lineup fairness when determining the suggestiveness of an identification procedure. Likewise, researchers often consider lineup fairness when comparing results across studies. Despite their importance, lineup fairness measures have received scant empirical attention and researchers inconsistently conduct and report...

PurposePeople tend to believe eyewitness testimony and have difficulty assessing the accuracy of eyewitness identifications. This study examines observers' perceptions of eyewitness identifications made under various line-up presentation and administration conditions. We also investigate whether observers' ability to discriminate between accurate a...

Prior research indicates that disguise negatively affects lineup identifications, but the mechanisms by which disguise works have not been explored, and different disguises have not been compared. In two experiments (Ns = 87 and 91) we manipulated degree of coverage by two different types of disguise: a stocking mask or sunglasses and toque (i.e.,...

Two types of variables impact face recognition: estimator variables that cannot be controlled and system variables that are under direct control by the criminal justice system. This article addresses some of the reasons that eyewitnesses are prone to making errors, particularly false identifications. It provides a discussion of the differences betw...

Facial recognition refers to our ability to indicate whether we have previously seen a face. This process involves perceptual, cognitive, and social components. We rely on our facial recognition system for mundane things such as recognizing acquaintances and more infrequent tasks such as identifying criminals from lineups.

Eye tracking was used to monitor participants' visual behaviour while viewing lineups in order to determine whether gaze behaviour predicted decision accuracy. Participants viewed taped crimes followed by simultaneous lineups. Participants (N = 34) viewed 4 target-present and 4 target-absent lineups. Decision time, number of fixations and duration...

Sequential lineups were offered as an alternative to the traditional simultaneous lineup. Sequential lineups reduce incorrect lineup selections; however, the accompanying loss of correct identifications has resulted in controversy regarding adoption of the technique. We discuss the procedure and research relevant to (1) the pattern of results found...

Malpass, Tredoux,and McQuiston-Surrett (2009), hereinafter 'MTM', provide comments on the sequentiallineup,researchcomparing sequentialand simultaneous lineups, and the policy implications of this literature. We will comment on points of agreement and disagreement. First, we agree with the following: (1) Peer review, publication of results, and div...

Educational activities often require students to conduct hypermedia information tasks. The intent of these tasks is generally to find information pursuant to a learning objective. However, the task itself could be viewed as a learning opportunity since students unintentionally learn peripheral material to the target material as they search through...