Legal Decision-Making in an Adult Rape Case Involving DNA Evidence.

This study investigated how jurors use deoxyribonucleic acid (DNA) evidence in an adult rape trial with a female victim and a male stranger defendant. Community members read a trial summary and then made case judgments (e.g., verdict). Results showed: (a) DNA evidence led to more pro-victim judgments (e.g., more guilty verdicts) than those who did not receive DNA evidence; (b) women were more pro-victim than men; (c) pro-victim judgments indirectly affected the presence of DNA evidence and verdict; and (d) the reason for a guilty verdict when DNA evidence was present typically noted a focus on the victim and DNA evidence.

The truth about snitches: an archival analysis of informant testimony.

Informants are witnesses who often testify in exchange for an incentive (i.e. jailhouse informant, cooperating witness). Despite the widespread use of informants, little is known about the circumstances surrounding their use at trial. This study content-analyzed trials from 22 DNA exoneration cases involving 53 informants. Because these defendants were exonerated, the prosecution informant testimony is demonstrably false. Informant characteristics including motivation for testifying, criminal history, relationship with the defendant and testimony were coded. Most informants were prosecution jailhouse informants; however, there were also defence jailhouse informants and prosecution cooperating witnesses. Regardless of informant type, most denied receiving an incentive, had criminal histories, were friends/acquaintances of the defendant and had testimonial inconsistencies. In closing statements, attorneys relied on informant testimony by either emphasizing or questioning its reliability. The impact of informant testimony on jurors' decisions is discussed in terms of truth-default theory (TDT), the fundamental attribution error and prosecutorial vouching.

The impact of fillers on lineup performance.

Filler siphoning theory posits that the presence of fillers (known innocents) in a lineup protects an innocent suspect from being chosen by siphoning choices away from that innocent suspect. This mechanism has been proposed as an explanation for why simultaneous lineups (viewing all lineup members at once) induces better performance than showups (one-person identification procedures). We implemented filler siphoning in a computational model (WITNESS, Clark, Applied Cognitive Psychology 17:629-654, 2003), and explored the impact of the number of fillers (lineup size) and filler quality on simultaneous and sequential lineups (viewing lineups members in sequence), and compared both to showups. In limited situations, we found that filler siphoning can produce a simultaneous lineup performance advantage, but one that is insufficient in magnitude to explain empirical data. However, the magnitude of the empirical simultaneous lineup advantage can be approximated once criterial variability is added to the model. But this modification works by negatively impacting showups rather than promoting more filler siphoning. In sequential lineups, fillers were found to harm performance. Filler siphoning fails to clarify the relationship between simultaneous lineups and sequential lineups or showups. By incorporating constructs like filler siphoning and criterial variability into a computational model, and trying to approximate empirical data, we can sort through explanations of eyewitness decision-making, a prerequisite for policy recommendations.

The effect of post-identification feedback, delay, and suspicion on accurate eyewitnesses.

We examined whether post-identification feedback and suspicion affect accurate eyewitnesses. Participants viewed a video event and then made a lineup decision from a target-present photo lineup. Regardless of accuracy, the experimenter either, informed participants that they made a correct lineup decision or gave no information regarding their lineup decision. Immediately following the lineup decision or after a 1-week delay, a second experimenter gave some of the participants who received confirming feedback reason to be suspicious of the confirming feedback. Following immediately after the confirming feedback, accurate witnesses did not demonstrate certainty inflation. However, after a delay accurate witnesses did demonstrate certainty inflation typically associated with confirming feedback. The suspicion manipulation only affected participants' certainty when the confirming feedback created certainty inflation. The results lend support to the accessibility interpretation of the post-identification feedback effect and the erasure interpretation of the suspicion effect.

Is manipulative intent necessary to mitigate the eyewitness post-identification feedback effect?

Feedback suggestive of mistaken eyewitnesses claiming that they identified the correct person leads to distorted retrospective judgments of certainty, view, and other testimony-relevant measures. This feedback effect can be significantly mitigated if witnesses later learn that the feedback source did not know which lineup member was the correct person and had a manipulative intent (post-feedback suspicion manipulation). We replicated the post-feedback suspicion effect and used a mistake condition showing that the manipulative intent is not a necessary component, thereby ruling out reactance-type interpretations of the post-feedback suspicion effect. Some conditions included instructions to ensure relevant processing of the feedback before the post-feedback suspicion manipulations, but these processing instructions did not mitigate the effect. The results suggest that these retrospective judgments (e.g., certainty, attention, view) remain malleable as new information unfolds.

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.

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 effects of accomplice witnesses and jailhouse informants on jury decision making.

The present study presents one of the first investigations of the effects of accomplice witnesses and jailhouse informants on jury decision-making. Across two experiments, participants read a trial transcript that included either a secondary confession from an accomplice witness, a jailhouse informant, a member of the community or a no confession control. In half of the experimental trial transcripts, the participants were made aware that the cooperating witness providing the secondary confession was given an incentive to testify. The results of both experiments revealed that information about the cooperating witness' incentive (e.g., leniency or reward) did not affect participants' verdict decisions. In Experiment 2, participant jurors appeared to commit the fundamental attribution error, as they attributed the motivation of the accomplice witness and jailhouse informant almost exclusively to personal factors as opposed to situational factors. Furthermore, both experiments revealed that mock jurors voted guilty significantly more often when there was a confession relative to a no confession control condition. The implications of the use of accomplice witness and jailhouse informant testimony 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.

Comparison of the efficacy of two name-learning techniques: expanding rehearsal and name-face imagery.

Two name-learning techniques were compared: expanding rehearsal and name-face imagery. Participants studied name-face associations and were given a cued recall test in which they were presented with a face and were to recall the name. They were presented with either an expanding rehearsal schedule (expanding condition), a distinctive facial feature coupled with a word phonologically similar to the last name and an interactive image linking the name and facial feature (name-face imagery condition), or a no memory (control) strategy. The expanding rehearsal schedule led to superior name learning relative to the name-face imagery and control conditions after a 15-min (Experiment 1) or 48-hr (Experiment 2) retention interval. In Experiment 3, the retrieval practice explanation was tested but not supported; we argue that an encoding variability interpretation is consistent with the overall pattern of results. Applied implications are also discussed.

Robust recollection rejection in the memory conjunction paradigm.

The present research provides compelling evidence for recollection rejection in the memory conjunction paradigm. In Experiment 1, warnings provided at time of test were shown to reduce memory conjunction errors. Moreover, the authors found substantial evidence of recollection rejection and phantom recollection. In Experiment 2, the authors manipulated how often study items were presented. Participants were told that they could earn a cash payoff for being accurate. Recognition of conjunction lures was lower in the multiple presentation condition. However, the payoff manipulation did not significantly interact with item type. The authors obtained evidence of robust recollection rejection from 3 different dependent measures. Consistent with Experiment 1, they also found evidence of phantom recollection. These findings provide evidence that recollection rejection can be quite robust in the memory conjunction paradigm.

Generative processing and false memories: when there is no cost.

Encoding manipulations (e.g., levels of processing) that facilitate retention often result in greater numbers of false memories, a pattern referred to as the more is less effect (M. P. Toglia, J. S. Neuschatz, & K. A. Goodwin, 1999). The present experiments explored false memories under generative processing. In Experiments 1-3, using Deese-Roediger-McDermott (DRM) lists with items that were either read or generated, the authors found recognition and recall tests indicated generation effects for true memories but no increases in false memories (i.e., generation at no cost). In Experiment 4, in a departure from the DRM methodology, a cuing procedure resulted in a more is less pattern for congruous generation,and a no cost pattern for incongruous generation. This highlights the critical distinction between these encoding contexts.

Effective warnings in the Deese-Roediger-McDermott false-memory paradigm: the role of identifiability.

These experiments document that warnings can substantially reduce false memories in the Deese-Roediger-McDermott (DRM) paradigm when the critical items are easily identifiable. Participants in a norming study identified the critical item after hearing a list of words. The lists with critical items that could be identified by the largest proportion of participants (high identifiable [HI] lists) and the smallest proportion of participants (low identifiable [LI] lists) were used in the experiment. Participants heard lists of words (e.g., bed, rest, doze) related to a critical item (e.g., sleep) and were warned about the nature of the lists before the study phase. The results indicated that warnings reduced false recognition of critical items for HI lists but not LI lists.