People viewed a security video and tried to identify the gunman from a photospread. The actual gunman was not in the photospread and all eyewitnesses made false identifications (n = 352). Following the identification, witnesses were given confirming feedback ("Good, you identified the actual suspect"), disconfirming feedback ("Actually, the suspect is number ''), or no feedback. The manipulations produced strong effects on the witnesses' retrospective reports of (a) their certainty, (b) the quality of view they had, (c) the clarity of their memory, (d) the speed with which they identified the person, and (e) several other measures. Eyewitnesses who were asked about their certainty prior to the feedback manipulation (Experiment 2) were less influenced, but large effects still emerged on some measures. The magnitude of the effect was as strong for those who denied that the feedback influenced them as it was for those who admitted to the influence.Eyewitness to a crime on viewing a lineup: ' 'Oh, my God . . . I don't know . . . It's one of those two . . . but I don't know . . . Oh, man . . . the guy a little bit taller than number two . . . It's one of those two, but I don't know.'' Eyewitness 30 min later, still viewing the lineup and having difficulty making a decision: "I don't know . . . number two?" Officer administering lineup: "Okay." Months later. . . at trial: "You were positive it was number two? It wasn't a maybe?" Answer from eyewitness: "There was no maybe about it . . . I was absolutely positive." (Missouri v. Huchting, 1996, p. 202) The eyewitness in the above case spent 30 min trying to identify her attacker from a lineup of four people. Her behavior at the time indicated a great deal of uncertainty about which, if any, of the people in the lineup was the attacker. Later, at trial, however, she recalls having been absolutely positive about her identification from the lineup. How could this happen? The current article tests

The authors investigated eyewitnesses' retrospective certainty (see G. L. Wells & A. L. Bradfield, 1999). The authors hypothesized that extemal influence from the lineup administrator would damage the certainty-accuracy relation by inflating the retrospective certainty of inaccurate eyewitnesses more than that of accurate eyewitnesses (N = 245). Two variables were manipulated: eyewitness accuracy (through the presence or absence of the culprit in the lineup) and feedback (confirming vs. control). Confirming feedback inflated retrospective certainty more for inaccurate eyewitnesses than for accurate eyewitnesses, significantly reducing the certainty-accuracy relation (from r = .58 in the control condition to r = .37 in the confirming feedback condition). Double-blind testing is recommended for lineups to prevent these external influences on eyewitnesses.

Giving eyewitnesses confirming feedback after they make a lineup identification (e.g., "Good. You identified the actual suspect.") inflates not only their recollections of how confident they were at the time of the identification, but also other testimony-relevant judgments, such as how good their view was, how much attention they paid during witnessing, and how quickly they identified the suspect. We replicated this postidentification-feedback effect with eyewitnesses who had made false identifications (N = 156), adding critical conditions in which after the identification but prior to the feedback, some eyewitnesses were given instructions to privately think about their confidence, their view, and other matters. Other eyewitnesses were given the same thought instructions subsequent to the feedback manipulation. Prior thought served to mitigate the effects of feedback, but subsequent thought did not. In addition, even without feedback, privately thinking about confidence had some confidence-inflating properties of its own.

The U.S. Supreme Court has outlined five criteria on which evaluations of eyewitness identifications should be based (certainty, view, attention, description, and time; Neil v. Biggers, 1972). We postulated that certainty plays a qualitatively different role from the four other Biggers criteria in evaluations of eyewitness identification testimony. Specifically, we hypothesized that participants would ignore reports on other criteria when certainty was high (the certainty-trumps hypothesis), but not when certainty was low. Participants (N ϭ 386) read a fictitious trial transcript in which three of the five Biggers criteria were manipulated (certainty, view, and attention, or certainty, description, and time) and completed a questionnaire. The certainty-trumps hypothesis was not supported. Instead, the Biggers criteria combined only as main effects, not interactions, supporting a summative hypothesis. Surprisingly, collateral effects indicated that manipulations of one criterion (e.g., certainty) affected perceptions of other criteria (e.g., attention and view) and vice versa. Implications of the results are discussed.

Two studies examined whether a criminal defendant's race influences Whites' sensitivity to legally relevant information. In Study 1, prosecution case strength ratings and guilt likelihood ratings were more sensitive to the strength of the defendant's alibi when he was Black than when he was White, if the experimental task was designed to elicit low processing motivation. Under high motivation, participants were equally sensitive to alibi strength, regardless of defendant race. In Study 2, the alibi strength manipulation was replaced with a manipulation of the effectiveness of the district attorney's cross-examination. As predicted, defense case strength ratings were more sensitive to the strength of the prosecutor's cross-examination with a Black defendant than with a White defendant-under low motivation. Under high motivation, sensitivity did not depend on defendant race. These results suggest that a Black defendant can elicit greater sensitivity to legally relevant information than will a White defendant.