Guidelines for empirically assessing the fairness of a lineup.

Abstract

Issues regarding the fairness of lineups used for criminal identification are discussed in the context of a distinction between nominal size and functional size. Nominal size (the number of persons in the lineup) is less important for determining the fairness of a lineup than is functional size (the number of lineup members resembling the criminal). Functional size decreases to the extent that the nonsuspect members of the lineup are easily ruled out as not being suspected by the police. The extent to which the identification of the suspect can be considered an independently derived piece of incriminating evidence is positively related to functional size. Empirical estimates of functional size can be obtained through pictures of the corporal lineup from which mock witnesses make guesses of whom they believe the police suspect. A distinction is made between a functional size approach and hypothesis testing approaches. Uses of functional size notions in the court, by police, and in research are discussed.

Unfair Lineups Make Witnesses More Likely to Confuse Innocent and Guilty Suspects

“…The long-standing explanation is that witnesses tend to select the person who looks most like the culprit, much like the way a student answering a multiple choice question tends to select the option that looks most like the right answer (Wells, 1984). Indeed, it is well established that when the only person who matches the witness's description of the culprit is the suspect, the witness tends to select the suspect instead of another lineup member (Doob & Kirshenbaum, 1973;Wells, Leippe, & Ostrom, 1979). More recent reviews and meta-analyses also show that when suspects look less like the other members of a lineup, witnesses identify the suspect more often (Clark, 2012;Fitzgerald, Price, Oriet, & Charman, 2013).…”

Towards a Science of Checklists

“…For example, in publications from the previous century, the development of items to measure progress in an operational process or to guide a user were seen as considerable, see e.g. [47]. In more recent literature, the view is that "figuring out what should form the content of a checklist for a […] problem is a nonetheless achievable ambition" [32].…”

Observation Ability: Determining and Extending Its Presence

“…This latter factor, expressed degree of confidence, is in fact a very prominant one in the minds of jurors. Several studies (for example, Wells, Ferguson, and Lindsay, 1981;Lindsay,Wells, and Rumpel, 1981) suggest that the confidence of a witness is a primary determinant in jurors' judgments, even though confidence is only marginally related to accuracy according to the same 4 studies and others (Brown, Deffenbacher, and Sturgill, 1977;Leippe, Wells, and Ostrom, 1978;Wells, Leippe, and Ostrom, 1979). Fallacious thinking of this sort is of course partICularly disqUieting when a confident witness is one whose testimony has been affected by certain accuracy-reducing factors.…”