New Insights on Expert Opinion About Eyewitness Memory Research.

Experimental psychologists investigating eyewitness memory have periodically gathered their thoughts on a variety of eyewitness memory phenomena. Courts and other stakeholders of eyewitness research rely on the expert opinions reflected in these surveys to make informed decisions. However, the last survey of this sort was published more than 20 years ago, and the science of eyewitness memory has developed since that time. Stakeholders need a current database of expert opinions to make informed decisions. In this article, we provide that update. We surveyed 76 scientists for their opinions on eyewitness memory phenomena. We compared these current expert opinions to expert opinions from the past several decades. We found that experts today share many of the same opinions as experts in the past and have more nuanced thoughts about two issues. Experts in the past endorsed the idea that confidence is weakly related to accuracy, but experts today acknowledge the potential diagnostic value of initial confidence collected from a properly administered lineup. In addition, experts in the past may have favored sequential over simultaneous lineup presentation, but experts today are divided on this issue. We believe this new survey will prove useful to the court and to other stakeholders of eyewitness research.

pyWitness 1.0: A python eyewitness identification analysis toolkit.

pyWitness is a python toolkit for recognition memory experiments, with a focus on eyewitness identification (ID) data analysis and model fitting. The current practice is for researchers to use different statistical packages to analyze a single dataset. pyWitness streamlines the process. In addition to conducting key data analyses (e.g., receiver operating characteristic analysis, confidence accuracy characteristic analysis), statistical comparisons, signal-detection-based model fits, simulated data generation, and power analyses are also possible. We describe the package implementation and provide detailed instructions and tutorials with datasets so that users can follow. There is also an online manual that is regularly updated. We developed pyWitness to be user-friendly, reduce human interaction with pre-processing and processing of data and model fits, and produce publication-ready plots. All pyWitness features align with open science practices, such that the algorithms, fits, and methods are reproducible and documented. While pyWitness is a python toolkit, it can also be used from R for users more accustomed to this environment.

The language of accurate and inaccurate eyewitnesses.

This article uses machine-learning techniques to examine people's use of verbal expressions of confidence. Across the field of academic psychology, it is often assumed that such statements reflect the same underlying information as numeric confidence ratings. We show that verbal confidence is not redundant with numeric confidence but instead contributes unique diagnostic value in predicting the accuracy of a response. We use eyewitness confidence in a lineup identification as our model paradigm. There is potentially great applied value in developing a machine-learning algorithm that can predict eyewitness identification accuracy, such as by reducing false convictions. To this end, we applied a machine-learning methodology to investigate the natural language of accurate and inaccurate eyewitnesses. This method revealed that verbal confidence statements provide rich diagnostic information about the likely accuracy of eyewitness identifications. Moreover, verbal confidence statements provide unique diagnostic information that traditional indicators of identification accuracy such as numeric confidence ratings and response times do not provide. However, the diagnostic value of an eyewitness confidence statement depends in part on the face recognition ability of the eyewitness: The natural language of strong face recognizers is more diagnostic than the natural language of weak face recognizers. These results are theoretically interesting but, from an applied perspective, this machine-learning methodology may prove useful to those in the criminal justice system who must evaluate eyewitnesses' verbal confidence statements. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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 with 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 with static photo lineups, and simultaneous interactive lineups enhanced witness discrimination accuracy compared with 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. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Child witness expressions of certainty are informative.

Children are frequently witnesses of crime. In the witness literature and legal systems, children are often deemed to have unreliable memories. Yet, in the basic developmental literature, young children can monitor their memory. To address these contradictory conclusions, we reanalyzed the confidence-accuracy relationship in basic and applied research. Confidence provided considerable information about memory accuracy, from at least age 8, but possibly younger. We also conducted an experiment where children in young (4-6 years), middle (7-9 years), and late (10-17 years) childhood (N = 2,205) watched a person in a video and then identified that person from a police lineup. Children provided a confidence rating (an explicit judgment) and used an interactive lineup-in which the lineup faces can be rotated-and we analyzed children's viewing behavior (an implicit measure of metacognition). A strong confidence-accuracy relationship was observed from age 10 and an emerging relationship from age 7. A constant likelihood ratio signal-detection model can be used to understand these findings. Moreover, in all ages, interactive viewing behavior differed in children who made correct versus incorrect suspect identifications. Our research reconciles the apparent divide between applied and basic research findings and suggests that the fundamental architecture of metacognition that has previously been evidenced in basic list-learning paradigms also underlies performance on complex applied tasks. Contrary to what is believed by legal practitioners, but similar to what has been found in the basic literature, identifications made by children can be reliable when appropriate metacognitive measures are used to estimate accuracy. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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.

Optimizing the selection of fillers in police lineups.

A typical police lineup contains a photo of one suspect (who is innocent in a target-absent lineup and guilty in a target-present lineup) plus photos of five or more fillers who are known to be innocent. To create a fair lineup in which the suspect does not stand out, two filler selection methods are commonly used. In the first, fillers are selected if they are similar in appearance to the suspect. In the second, fillers are selected if they possess facial features included in the witness's description of the culprit (e.g., "20-y-old white male"). The police sometimes use a combination of the two methods by selecting description-matched fillers whose appearance is also similar to that of the suspect in the lineup. Decades of research on which approach is better remains unsettled. Here, we tested a counterintuitive prediction made by a formal model based on signal detection theory: From a pool of acceptable description-matched photos, selecting fillers whose appearance is otherwise dissimilar to the suspect should increase the hit rate without affecting the false-alarm rate (increasing discriminability). In Experiment 1, we confirmed this prediction using a standard mock-crime paradigm. In Experiment 2, the effect on discriminability was reversed (as also predicted by the model) when fillers were matched on similarity to the perpetrator in both target-present and target-absent lineups. These findings suggest that signal-detection theory offers a useful theoretical framework for understanding eyewitness identification decisions made from a police lineup.

Designing police lineups to maximize memory performance.

How can lineups be designed to elicit the best achievable memory performance? One step toward that goal is to compare lineup procedures. In a recent comparison of U.S. and U.K. lineup procedures, discriminability and reliability was better when memory was tested using the U.S. procedure. However, because there are so many differences between the procedures, it is unclear what explains this superior performance. The main goal of the current research is, therefore, to systematically isolate the differences between the U.S. and U.K. lineups to determine their effects on discriminability and reliability. In 5 experiments, we compared (a) presentation format: simultaneous versus sequential; (b) stimulus format: photos versus videos; (c) number of views: 1-lap versus 2-lap versus choice in both video and photo lineups; and (d) lineup size: 6- versus 9-lineup members. Most of the comparisons did not show appreciable differences, but one comparison did: simultaneous presentation yielded better discriminability than sequential presentation. If the results replicate, then policymakers should recommend using a simultaneous lineup procedure. Moreover, consistent with previous research, identifications made with high confidence were higher in reliability than identifications made with low confidence. Thus, official lineup protocols should require collecting confidence because of the diagnostic value added. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The effects of verbal descriptions on performance in lineups and showups.

Verbally describing a face has been found to impair subsequent recognition of that face from a photo lineup, a phenomenon known as the verbal overshadowing effect (Schooler & Engstler-Schooler, 1990). Recently, a large direct replication study successfully reproduced that original finding (Alogna et al., 2014). However, in both the original study and the replication studies, memory was tested using only target-present lineups (i.e., lineups containing the previously seen target face), making it possible to compute the correct identification rate (correct ID rate; i.e., the hit rate) but not the false identification rate (false ID rate; i.e., the false alarm rate). Thus, the lower correct ID rate for the verbal condition could reflect either reduced discriminability or a conservative criterion shift relative to the control condition. In four verbal overshadowing experiments reported here, we measured both correct ID rates and false ID rates using photo lineups (Experiments 1 and 2) or single-photo showups (Experiments 3 and 4). The experimental manipulation (verbally describing the face or not) occurred either immediately after encoding (Experiments 1 and 3) or 20-min after encoding (Experiments 2 and 4). In the immediate condition, discriminability did not differ between groups, but in the delayed condition, discriminability was lower in the verbal description group (i.e., a verbal overshadowing effect was observed). A fifth experiment found that the effect of the immediate-versus-delayed manipulation may be attributable to a change in the content of verbal descriptions, with the ratio of diagnostic to generic facial features in the descriptions decreasing as delay increases. (PsycINFO Database Record

US line-ups outperform UK line-ups.

In the USA and the UK, many thousands of police suspects are identified by eyewitnesses every year. Unfortunately, many of those suspects are innocent, which becomes evident when they are exonerated by DNA testing, often after having been imprisoned for years. It is, therefore, imperative to use identification procedures that best enable eyewitnesses to discriminate innocent from guilty suspects. Although police investigators in both countries often administer line-up procedures, the details of how line-ups are presented are quite different and an important direct comparison has yet to be conducted. We investigated whether these two line-up procedures differ in terms of (i) discriminability (using receiver operating characteristic analysis) and (ii) reliability (using confidence-accuracy characteristic analysis). A total of 2249 participants watched a video of a crime and were later tested using either a six-person simultaneous photo line-up procedure (USA) or a nine-person sequential video line-up procedure (UK). US line-up procedure yielded significantly higher discriminability and significantly higher reliability. The results do not pinpoint the reason for the observed difference between the two procedures, but they do suggest that there is much room for improvement with the UK line-up.

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.