Steve D. Charman

Building Face Composites Can Harm Lineup Identification Performance

Face composite programs permit eyewitnesses to build likenesses of target faces by selecting facial features and combining them into an intact face. Research has shown that these composites are generally poor likenesses of the target face. Two experiments tested the proposition that this composite-building process could harm the builders memory for the face. In Experiment 1 (n = 150), the authors used 50 different faces and found that the building of a composite reduced the chances that the person could later identify the original face from a lineup when compared with no composite control conditions or with yoked composite-exposure control conditions. In Experiment 2 (n = 200), the authors found that this effect generalized to a simulated-crime video, but mistaken identifications from target-absent lineups were not inflated by composite building.

The Selective Cue Integration Framework: A Theory of Postidentification Witness Confidence Assessment.

The current manuscript proposes a theory of how witnesses assess their confidence following a lineup identification, called the selective cue integration framework (SCIF). Drawing from past research on the postidentification feedback effect, the SCIF details a three-stage process of confidence assessment that is based largely on a conceptualization of feedback-produced confidence inflation as an attitude change phenomenon. According to the SCIF, when asked to assess their confidence, witnesses assess the strength of their internal accuracy cues (assessment stage). If weak, witnesses look specifically for external accuracy cues that can justify their identification decision (search stage). Finally, these justifying external cues are submitted to a credibility check (evaluation stage); if no credibility-undermining information is uncovered, they become integrated into ones confidence assessment. Three studies used college students as mock-witnesses to test predictions derived from the SCIF. In study 1a, lineup identification confidence was unaffected by disconfirming feedback unless that statement recanted previously administered confirming feedback, suggesting the existence of different stages in the confidence assessment process. Study 1b demonstrated that the effects of recanted feedback depend only on a discrediting of the feedback itself, and not on the discrediting of the identification. Study 2 demonstrated the generality of the SCIF by showing its predictive ability within a novel and methodologically improved postidentification cowitness feedback paradigm. Results across all three studies supported the SCIF as a theoretical framework for witness confidence assessment, suggest a new means of eliminating the feedback effect, and unite postidentification feedback and cowitness phenomena under a common theoretical umbrella.

Appearance-change instruction effects on eyewitness lineup identification accuracy are not moderated by amount of appearance change.

Instructing witnesses that a criminal may have changed appearance prior to showing them a lineup has been shown to increase false identifications without increasing correct identifications (S. D. Charman & G. L. Wells, 2007, Is the appearance-change instruction a good idea? Law and Human Behavior, Vol. 31, pp. 3-22). However, the generalizability of the effects of this appearance-change instruction (ACI) is unknown, and there are reasons to believe that the instructions effects may be moderated by the amount of appearance change the criminal has actually undergone. The current study tested this hypothesis. Undergraduate students (N = 315) were exposed to a series of target faces and lineups, some of which contained the target and some of which did not, and made identification decisions. Half of the participants received a standard ACI prior to each lineup; the other half did not. The targets varied with respect to the amount to which their appearance had changed. Results indicated that the ACI inflated false identifications without inflating correct identifications, and that these effects did not depend on the amount of appearance change the target had undergone. Current recommendations to administer the ACI seem to be unfounded and may be harmful to the reliability of identification evidence.

Effects of cannabis on eyewitness memory: A field study

Summary Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field setting. One hundred twenty visitors of coffee shops in Amsterdam viewed a videotaped criminal event, were interviewed about the event, and viewed a target‐present or target‐absent lineup. Witnesses under the influence of cannabis remembered significantly fewer correct details about the witnessed event than did sober witnesses, with no difference in incorrect recall. Cannabis use was not significantly associated with lineup identification performance, but intoxicated witnesses were significantly better at judging whether their lineup identification was accurate. Theoretical and practical implications of the findings are discussed.