Do Prophylactics Prevent Inflation? Post-identification Feedback and the Effectiveness of Procedures to Protect Against Confidence-inflation in Earwitnesses

After viewing or hearing a recorded simulated crime, participants were asked to identify the offender’s voice from a target-absent audio lineup. After making their voice identification, some participants were either given confirming feedback or no feedback. The feedback manipulation in experiment 1 led to higher ratings of participants’ identification certainty, as well as higher ratings on retrospective confidence reports, in both the immediate and delay groups. Earwitnesses who were asked about their identification certainty prior to the feedback manipulation (experiment 2) did not demonstrate the typical confidence-inflation associated with confirming feedback if they were questioned about the witnessing experience immediately; however, the effects returned after a week-long retention interval. The implications for the differential forgetting and internal-cues hypotheses are discussed.     

The Mitigating Effects of Suspicion on Post-Identification Feedback and on Retrospective Eyewitness Memory

Three studies examined procedures for reducing the post-identification feedback effect. After viewing a video event, participants were then asked to identify a suspect from a target-absent photo lineup. After making their identification, some participants were given information suggesting that their identification was correct, while others were given no information about the accuracy of their identification. Some participants who received confirming feedback were also given reasons to entertain suspicion regarding the motives of the lineup administrator, either immediately (Experiment 1) or after a one-week retention interval (Experiment 2). Suspicious perceivers failed to demonstrate the confidence inflation effects typically associated with confirming post-identification feedback. In Experiment 3, the confidence prophylactic effect was tested both immediately and after a one-week retention interval. The effect of confidence prophylactic varied with retention interval such that it eliminated the effects of post-identification feedback immediately but not after a retention interval. However, the suspicion manipulation eliminated the post-identification feedback effects at both time intervals. Both theoretical and practical implications are discussed.     

The Effects of Pre-admonition Suggestions on Eyewitnesses’ Choosing Rates and Retrospective Identification Judgments

Pre-admonition suggestion is an identification-relevant comment made to an eyewitness by a lineup administrator before the lineup admonition. Quinlivan et al. (2012) found that their suggestion inflated mistaken identification rates and retrospective identification. However, the suggestion used was a compound statement, making it unclear which component influenced choosing rates. The current experiment was conducted to parse out the effects. Participants (N = 211) viewed a crime video and received either one component of the compound suggestion (a suggestion to pick or that the witness had paid substantial attention), both components, or no suggestion. All participants received an admonition, made an identification choice, and answered questions about their witnessing experience. The results demonstrated that the pick suggestion increased mistaken identifications from a perpetrator-absent lineup whereas the effects of the attention suggestion were restricted to the retrospective judgments. These results show support for the role of secondary (non-memorial) processes in eyewitness identification.     

Age differences (or lack thereof) in discriminability for lineups and showups

Previous research reveals that showups are an inferior eyewitness identification procedure to lineups, but no single study has compared younger and older adults' identification decisions for both of these procedures. We had witnesses watch a mock crime video and then make an identification decision from a fair lineup, a biased lineup, or a showup that contained the perpetrator or a designated innocent suspect. Receiver operating characteristic (ROC) analysis showed that identification accuracy was higher from a lineup than from a showup for both age groups, even if the lineup was biased. In addition, calibration curves revealed that witnesses were underconfident when choosing from a fair lineup but overconfident when choosing from a showup. These results reinforce prior research asserting the superiority of lineups over showups.     

Do pre‐admonition suggestions moderate the effect of unbiased lineup instructions?

We examined the additive and interactive effects of pre‐admonition suggestion and lineup instructions (biased or unbiased) on eyewitness identification rates. Participants watched a mock crime video, completed a target‐absent lineup identification, and completed a retrospective memory questionnaire. Prior to attempting an identification, participants were either exposed or not exposed to pre‐admonition suggestions and received biased or unbiased lineup instructions. The pre‐admonition suggestion indicated that it was likely that the perpetrator was in the lineup (surely, you can pick the perpetrator). The pre‐admonition suggestion increased false identification in the unbiased lineup condition. Furthermore, those who received the pre‐admonition suggestion were more certain in their identifications as well as other testimony‐relevant judgments than were those who did not receive the pre‐admonition suggestion. These results suggest that pre‐lineup suggestion can mitigate the beneficial effects of unbiased lineup instructions.     

Does Post-identification Feedback Affect Evaluations of Eyewitness Testimony and Identification Procedures?

Two experiments were conducted to test whether post-identification feedback affects evaluations of eyewitnesses. In Experiment 1 (N = 156), evaluators viewed eyewitness testimony. They evaluated witnesses who received confirming post-identification feedback as more accurate and more confident, among other judgments, compared with witnesses who received disconfirming post-identification feedback or no feedback. This pattern persisted regardless of whether the witness’s confidence statement was included in the testimony. In Experiment 2 (N = 161), witness evaluators viewed the actual identification procedure in which feedback was delivered. Instructions to disregard the feedback were manipulated. Again, witnesses who received confirming feedback were assessed more positively. This pattern occurred even when witness evaluators received instructions to disregard the feedback. These experiments are the first to confirm researchers’ assumptions that feedback effects on witnesses translate to changes in judgments of those witnesses.