Sheila M. Rydell's scientific contributions

An eyewitness takes the stand and describes salient aspects of an event that he or she witnessed several months earlier. Then, in the hush of the courtroom, points to the defendant and says “That's him. That's the man I saw.” Simple, clean, and convincing. And therein rests the problem; what appears to be a simple identification is in fact the result of a series of complex and potentially unreliable social and cognitive events that began unfolding several months earlier when the event was originally witnessed. This chapter, and much of the empirical research on which it is based, operates on an assumption that there are two sources of unreliability in eyewitness accounts. First, there are some inherent limitations in human information processing. These limitations exist at sensory levels (for example, Sperling, 1960), attentional levels (for example, Broadbent, 1958; Deutsch & Deutsch, 1963; Triesman, 1964), and memory levels (for example, Miller, 1956; Atkinson & Shiffrin, 1968). But inaccuracies in eyewitness accounts are not entirely attributable to human imperfections in sensation, perception, and memory. The second source of inaccuracy in eyewitness accounts can be attributed to the methods the justice system uses to obtain information from eyewitnesses. The work of Elizabeth Loftus on the effects of misleading questions serves to make this point (see Loftus, 1979; and this volume). The account one gets from an eyewitness depends very much on the methods used to solicit the information. The study of how to improve eyewitness accuracy by manipulating the methods used to obtain information from eyewitnesses is known as a systemvariable approach to eyewitness research (Wells, 1978).

Thefts were staged for 252 eyewitnesses using 7 different confederate thieves. Photospreads were constructed for each eyewitness to test a proposal regarding strategies for selecting lineup distractors (C. A. Luus and G. L. Wells, 1991). Distractors were selected to resemble a suspect or to match the eyewitness's description of the culprit. A mismatch-description strategy was included for comparison and contrast with the other 2 strategies. The match-description strategy produced both a low false-identification rate and a high accurate-identification rate. The mismatch-description strategy was unable to hold down false-identification rates, and the resemble-suspect strategy failed to secure acceptable rates of accurate identification. The match-description strategy captures the best features of the mismatch-description and resemble-suspect strategies without also capturing their worst features. (PsycINFO Database Record (c) 2012 APA, all rights reserved)