ROCs in Eyewitness Identification: Instructions vs. Confidence Ratings

From the perspective of signal-detection theory, different lineup instructions may induce different levels of response bias (Clark, 2005). If so, then collecting correct and false identification rates across different instructional conditions will trace out the ROC – the same ROC that, theoretically, could also be traced out from a single instruction condition in which each eyewitness decision is accompanied by a confidence rating. We tested whether the two approaches do in fact yield the same ROC. Participants were assigned to a confidence rating condition or to an instructional biasing condition (liberal, neutral, unbiased, or conservative). After watching a video of a mock crime, participants were presented with instructions followed by a 6-person simultaneous photo lineup. The ROCs from both methods were similar, but they were not exactly the same. These findings have potentially important policy implications for how the legal system should go about controlling eyewitness response bias

Assessing Theoretical Conclusions With Blinded Inference to Investigate a Potential Inference Crisis

Scientific advances across a range of disciplines hinge on the ability to make inferences about unobservable theoretical entities on the basis of empirical data patterns. Accurate inferences rely on both discovering valid, replicable data patterns and accurately interpreting those patterns in terms of their implications for theoretical constructs. The replication crisis in science has led to widespread efforts to improve the reliability of research findings, but comparatively little attention has been devoted to the validity of inferences based on those findings. Using an example from cognitive psychology, we demonstrate a blinded-inference paradigm for assessing the quality of theoretical inferences from data. Our results reveal substantial variability in experts’ judgments on the very same data, hinting at a possible inference crisis

Rethinking familiarity : remember/know judgments in free recall

Although frequently used with recognition, a few studies have used the Remember/Know procedure with free recall. In each case, participants gave Know judgments to a significant number of recalled items (items that were presumably not remembered on the basis of familiarity). What do these Know judgments mean? We investigated this issue using a source memory/free-recall procedure. For each word that was recalled, participants were asked to (a) make a confidence rating on a 5-point scale, (b) make a Remember/Know judgment, and (c) recollect a source detail. The large majority of both Remember judgments and Know judgments were made with high confidence and high accuracy, but source memory was nevertheless higher for Remember judgments than for Know judgments. These source memory results correspond to what is found using recognition, and they raise the possibility that Know judgments in free recall identify the cue-dependent retrieval of item-only information from an episodic memory search set. In agreement with this idea, we also found that the temporal dynamics of free recall were similar for high-confidence Remember and high-confidence Know judgments (as if both judgments reflected retrieval from the same search set). If Know judgments in free recall do in fact reflect the episodic retrieval of item-only information, it seems reasonable to suppose that the same might be true of high-confidence Know judgments in recognition. If so, then a longstanding debate about the role of the hippocampus in recollection and familiarity may have a natural resolution

Perpetrator pose reinstatement during a lineup test increases discrimination accuracy

We examined how encoding view influences the information that is stored in and retrieved from memory during an eyewitness identification task. Participants watched a mock crime and we varied the angle from which they viewed the perpetrator. In Experiment 1, participants (N = 2904) were tested with a static photo lineup; the viewing angle of the lineup members was the same or different from the perpetrator at encoding. In Experiment 2, participants (N = 1430) were tested with a novel interactive lineup in which they could rotate the lineup faces into any angle. In both experiments, discrimination accuracy was greater when the viewing angle at encoding and test matched. Participants reinstated the angle of the interactive faces to match their encoding angle. Our results highlight the importance of encoding specificity for eyewitness identification, and show that people actively seek out information in the testing environment that matches the study environment to aid memory retrieval

Active exploration of faces in police lineups increases discrimination accuracy

Eyewitness identifications play a key role in the justice system, but eyewitnesses can make errors, often with profound consequences. We used findings from basic science and innovative technologies to develop and test whether a novel interactive lineup procedure, wherein witnesses can rotate and dynamically view the lineup faces from different angles, improves witness discrimination accuracy compared to a widely used procedure in laboratories and police forces around the world—the static frontal-pose photo lineup. No novel procedure has previously been shown to improve witness discrimination accuracy. In Experiment 1, participants (N=220) identified culprits from sequentially presented interactive lineups or static frontal-pose photo lineups. In Experiment 2, participants (N=8,507) identified culprits from interactive lineups that were either presented sequentially, simultaneously wherein the faces could be moved independently, or simultaneously wherein the faces moved jointly into the same angle. Sequential interactive lineups enhanced witness discrimination accuracy compared to static photo lineups, and simultaneous interactive lineups enhanced witness discrimination accuracy compared to sequential interactive lineups. These finding were true both when participants viewed suspects who were of the same or different ethnicity/race as themselves. Our findings exemplify how basic science can be used to address the important applied policy issue on how best to conduct a police lineup and reduce eyewitness errors