Simultaneous Lineups Research Articles

A rate-them-all lineup procedure increases information but reduces discriminability.

Prior research has investigated ways to optimize identification performance, but an open question concerns exactly what variable should be optimized. One reasonable way to optimize performance is to maximize discriminability, which is achieved by increasing correct identifications of guilty suspects while simultaneously decreasing false identifications of innocent suspects. Another reasonable way to optimize performance is to maximize the information about the guilt or innocence of the suspect, which is best achieved by ensuring that a confidence rating is always made to the suspect. In a typical lineup, however, limited information about the suspect is obtained if the witness picks a filler or rejects the lineup. One proposed solution to that problem is to have the witness provide a confidence rating to every member of the lineup (a rate-them-all lineup). But what effect, if any, does a rate-them-all procedure have on discriminability? To answer that question, we compared a rate-them-all lineup procedure to standard simultaneous lineup and showup procedures using receiver operating characteristic analysis. In terms of discriminability, the rate-them-all procedure was diagnostically inferior to both. A reasonable goal for future research is to make use of theoretical models of eyewitness identification to simultaneously maximize both discriminability and information gain. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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.

Response bias modulates the confidence‐accuracy relationship for both positive identifications and lineup rejections in a simultaneous lineup task

AbstractIn recent years, the use of calibration analysis and confidence‐accuracy characteristic analysis has revealed the confidence‐accuracy relationship for positive identification (ID) made from a lineup is often strong. At the same time, the confidence‐accuracy relationship for lineup rejections is typically much weaker. Why the relationship is often weak for lineup rejections remains unclear. Here, we report two experiments testing a prediction that follows from signal detection theory. Specifically, this theory predicts that one determinant of the strength of the confidence‐accuracy relationship for both positive IDs and lineup rejections is response bias. Theoretically, inducing a more conservative response bias should weaken the confidence‐accuracy relationship for positive IDs while strengthening it for lineup rejections. The two experiments reported here support this prediction.

The effect of surgical masks on identification decisions from masked and unmasked lineups

While research has shown that wearing a disguise hinders lineup identifications, less is known about how to conduct lineups in cases of disguised perpetrators. We examined the influence of surgical masks, worn during a crime event (encoding) and within lineups (retrieval), on eyewitness identification accuracy. In our experiment, 452 participants watched a mock-crime video and identified the perpetrator from either a target-present or a target-absent simultaneous lineup. Contrary to expectations based on the encoding specificity principle, we did not find that matching the presence of masks in the lineup to the encoding condition increased identification accuracy. Instead, compared to the condition with no masks at encoding and retrieval, the presence of masks at either stage negatively affected discriminability and undermined the predictive utility of confidence and decision time. Our findings indicate that when a witness has encountered a masked perpetrator, presenting them with a masked lineup may not be necessary.

Measuring lineup fairness from eyewitness identification data using a multinomial processing tree model

The mock-witness task is typically used to evaluate the fairness of lineups. However, the validity of this task has been questioned because there are substantial differences between the tasks for mock witnesses and eyewitnesses. Unlike eyewitnesses, mock witnesses must select a person from the lineup and are alerted to the fact that one lineup member might stand out from the others. It therefore seems desirable to base conclusions about lineup fairness directly on eyewitness data rather than on mock-witness data. To test the importance of direct measurements of biased suspect selection in eyewitness identification decisions, we assessed the fairness of lineups containing either morphed or non-morphed fillers using both mock witnesses and eyewitnesses. We used Tredoux’s E and the proportion of suspect selections to measure lineup fairness from mock-witness choices and the two-high threshold eyewitness identification model to measure the biased selection of the suspects directly from eyewitness identification decisions. Results obtained in the mock-witness task and the model-based analysis of data obtained in the eyewitness task converged in showing that simultaneous lineups with morphed fillers were significantly more unfair than simultaneous lineups with non-morphed fillers. However, mock-witness and eyewitness data converged only when the eyewitness task mimicked the mock-witness task by including pre-lineup instructions that (1) discouraged eyewitnesses to reject the lineups and (2) alerted eyewitnesses that a photograph might stand out from the other photographs in the lineup. When a typical eyewitness task was created by removing these two features from the pre-lineup instructions, the morphed fillers no longer lead to unfair lineups. These findings highlight the differences in the cognitive processes of mock witnesses and eyewitnesses and they demonstrate the importance of measuring lineup fairness directly from eyewitness identification decisions rather than indirectly using the mock-witness task.

A stronger memory for the perpetrator may attenuate effects of the identification procedure on eyewitness accuracy

AbstractThe identification procedure can greatly affect eyewitness performance, but this may be contingent upon a relatively weak memory for the perpetrator. In a large preregistered experiment (N = 13,728), we manipulated memory strength and tested participants with a target‐present or ‐absent showup or lineup (size 3 or 6). All fillers were description‐matched but were of low or high similarity with the target. We replicated the advantage of fair simultaneous lineups over showups and the advantage of low‐ over high‐similarity fillers when memory for the perpetrator's face was weaker (short exposure duration), but both effects were significantly reduced when memory was stronger. There was no effect of lineup size regardless of memory strength or filler similarity. We conclude that some recommendations to police may be more robust than others across changes in estimator variables such as memory strength and that more research is needed on interactions between estimator and system variables.

The reveal procedure: A way to enhance evidence of innocence from police lineups.

Recent work has established that high-confidence identifications (IDs) from a police lineup can provide compelling evidence of guilt. By contrast, when a witness rejects the lineup, it may offer only limited evidence of innocence. Moreover, confidence in a lineup rejection often provides little additional information beyond the rejection itself. Thus, although lineups are useful for incriminating the guilty, they are less useful for clearing the innocent of suspicion. Here, we test predictions from a signal-detection-based model of eyewitness ID to create a lineup that is capable of increasing information about innocence. Our model-based simulations suggest that high-confidence rejections should exonerate many more innocent suspects and do so with higher accuracy if, after a witness rejects a lineup but before they report their confidence, they are shown the suspect and asked, "How sure are you that this person is not the perpetrator?" Participants (N = 3,346) recruited from Amazon Mechanical Turk watched a 30-s mock-crime video of a perpetrator. Afterward, they were randomly assigned to lineup procedures using a 2 (standard control vs. reveal condition) × 2 (target present vs. target absent) design. A standard simultaneous lineup served as the control condition. The reveal condition was identical to the control condition except in cases of lineup rejection: When a lineup rejection occurred, the suspect appeared on the screen, and participants provided a confidence rating indicating their belief that the suspect was not the perpetrator. The reveal procedure increased both the accuracy and frequency of high-confidence rejections relative to the standard simultaneous lineup. Collecting a confidence rating about the suspect after a lineup is rejected may make it possible to quickly clear innocent suspects of suspicion and reduce the amount of contact that innocent people have with the legal system. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The effect of lineup size on eyewitness identification.

Eyewitness identification via lineup procedures is an important and widely used source of evidence in criminal cases. However, the scientific literature provides inconsistent guidance on a very basic feature of lineup procedure: lineup size. In two experiments, we examined whether the number of fillers affects diagnostic accuracy in a lineup, as assessed with receiver-operating characteristic (ROC) analysis. Showups (identification procedures with one face) led to lower discriminability than simultaneous lineups. However, in neither experiment did the number of fillers in a lineup affect discriminability. We also evaluated competing models of decision-making from lineups. This analysis indicated that the standard Independent Observations (IO) model, which assumes a decision rule based on the comparison of memory strength signals generated by each face in a lineup, is incapable of reproducing the lower level of performance evident in showups. We could not adjudicate between the Ensemble model, which assumes a decision rule based on the comparison of the strength of each face with the mean strength across the lineup, and a newly introduced Dependent Observations model, which adopts the same decision rule as the IO model, but with correlated signals across faces. We draw lessons for users of lineup procedures and for basic research on eyewitness decision making. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Retraction of Mansour et al. (2012).

Reports the retraction of "Impact of disguise on identification decisions and confidence with simultaneous and sequential lineups" by Jamal K. Mansour, Jennifer L. Beaudry, Michelle I. Bertrand, Natalie Kalmet, Elisabeth I. Melsom and Roderick C. L. Lindsay (Law and Human Behavior, 2012[Dec], Vol 36[6], 513-526). The article reported two separate experiments and included a re-analysis of the data from both experiments combined. The authors recently discovered data entry and transformation errors that affected the descriptive and inferential results in both experiments and, to a small extent, the conclusions drawn following each individual experiment. The errors did not affect the overall conclusions described in the General Discussion section for both experiments beginning on p. 527. All of the authors joined in the request for this retraction. They accept and share responsibility for not identifying these errors prior to publication. The authors have agreed to correct the errors and we have accepted the revised manuscript, and it now published: "Impact of Disguise on Identification Decisions and Confidence With Simultaneous and Sequential Lineups" by Jamal K. Mansour, Jennifer L. Beaudry, Michelle I. Bertrand, Natalie Kalmet, Elisabeth I. Melsom, and Roderick C. L. Lindsay (Law and Human Behavior, 2020, Vol. 44, No. 6, 502-515. https://doi.org/10.1037/lhb0000427). (The following abstract of the original article appeared in record 2012-04571-001.) Prior research indicates that disguise negatively affects lineup identifications, but the mechanisms by which disguise works have not been explored, and different disguises have not been compared. In two experiments (Ns = 87 and 91) we manipulated degree of coverage by two different types of disguise: a stocking mask or sunglasses and toque (i.e., knitted hat). Participants viewed mock-crime videos followed by simultaneous or sequential lineups. Disguise and lineup type did not interact. In support of the view that disguise prevents encoding, identification accuracy generally decreased with degree of disguise. For the stocking disguise, however, full and 2/3 coverage led to approximately the same rate of correct identifications-which suggests that disrupting encoding of specific features may be as detrimental as disrupting a whole face. Accuracy was most affected by sunglasses and we discuss the role metacognitions may have played. Lineup selections decreased more slowly than accuracy as coverage by disguise increased, indicating witnesses are insensitive to the effect of encoding conditions on accuracy. We also explored the impact of disguise and lineup type on witnesses' confidence in their lineup decisions, though the results were not straightforward. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Eyewitness memory in the news can affect the strategic regulation of memory reporting

ABSTRACT The public is increasingly exposed to news about eyewitness memory errors. This study draws from the strategic memory regulation framework [Goldsmith, M., Koriat, A., & Weinberg-Eliezer, A. (2002). Strategic regulation of grain size memory reporting. Journal of Experimental Psychology: General, 131(1), 73–95. https://doi.org/10.1037/0096-3445.131.1.73] to make predictions about how eyewitness memory reporting is affected by exposure to such reports. In Experiment 1, participants (n = 226) viewed a mock crime, were exposed to a fictitious news report about eyewitness memory accuracy (memory is accurate, memory is inaccurate, or a control condition), and then recalled the mock crime. Participants who read that eyewitness memory is inaccurate were less confident in their memory accuracy and reported less information about the mock crime compared to those in the other conditions. The specificity and accuracy of recall did not vary across conditions, however. In Experiment 2, participants (n = 2,491) watched a mock crime and were asked to identify the perpetrator from a simultaneous lineup. Participants who read that eyewitness memory is inaccurate evaluated their memory for the mock crime as relatively poorer but their lineup decisions did not differ compared to other participants. This suggests that news about eyewitness memory inaccuracy affects how people evaluate their memory capability, and differentially affects memory output depending on the memory task.

Do sequential lineups impair underlying\xa0discriminability?

Debate regarding the best way to test and measure eyewitness memory has dominated the eyewitness literature for more than 30 years. We argue that resolution of this debate requires the development and application of appropriate measurement models. In this study we developed models of simultaneous and sequential lineup presentations and used these to compare these procedures in terms of underlying discriminability and response bias, thereby testing a key prediction of diagnostic feature detection theory, that underlying discriminability should be greater for simultaneous than for stopping-rule sequential lineups. We fit the models to the corpus of studies originally described by Palmer and Brewer (2012, Law and Human Behavior, 36(3), 247–255), to data from a new experiment and to eight recent studies comparing simultaneous and sequential lineups. We found that although responses tended to be more conservative for sequential lineups there was little or no difference in underlying discriminability between the two procedures. We discuss the implications of these results for the diagnostic feature detection theory and other kinds of sequential lineups used in current jurisdictions.

Line-Up Image Position in Simultaneous and Sequential Line-Ups: The Effects of Age and Viewing Distance on Selection Patterns.

It is known that children and older adults produce more false alarms in target absent line-ups and that weaker facial encoding increases choosing bias. However, there has been no investigation of how age or facial encoding strength impacts line-up position selections in either sequential or simultaneous line-ups. In the present study, we presented participants with four live targets (one by one) while manipulating sequential and simultaneous line-ups between participants and target present and target absent line-ups within participants. In order to investigate facial encoding strength, we presented the targets at distances between 5 and 110 m. Our main hypotheses were that children due to deficits with inhibition would be more biased toward indiscriminate selections in the first position of sequential line-ups compared with subsequent line-up positions and that first position selections would increase for all age groups as facial encoding became weaker. In simultaneous line-ups, we expected to find a top row bias. In our sample (N = 1,588 participants; 6–77 years), we found that younger children (6–11 years) and the oldest adults (60–77 years) showed a first position bias in sequential line-ups, and as facial encoding became weaker, all age groups (6–11, 12–17, 18–44, 45–59, and 60–77 years) showed an increased tendency to make first position selections. We also found a weak top row preference in simultaneous line-ups, which was moderated by age and increased distance. The main finding is that the results suggest that younger children and the oldest adults had a tendency toward a first position selection bias in sequential line-ups. Based on the combined results, we recommend caution when using sequential line-ups with younger children or older adults.

Testing a new lineup procedure with children: The elimination with wildcard

Preschoolers' (4- to 7-year-olds) recall and correct rejection rates using the simultaneous, wildcard, elimination, and a new lineup; the elimination with wildcard were compared. The new lineup uses the traditional two judgement procedure inherent to the elimination lineup but modifies Judgement 2 by providing a wildcard rejection. Participants (N = 116) watched a 4-min video of a male target. Each participant was asked to free recall the details of the video and to answer cued recall questions about the target's appearance. Participants were then given one of the four target-absent lineups. Separating by older and younger preschoolers, the 4/5-year-olds reported an average of 1.18 descriptors with an 87% accuracy rate, while the 6/7-year-olds reported an average of 1.93 descriptors with a 91% accuracy rate. For both the older and younger preschoolers, correct rejection rates were highest for the new elimination with wildcard lineup, followed by the simultaneous lineup.

Using machine learning analyses to explore relations between eyewitness lineup looking behaviors and suspect guilt.

We conducted 2 experiments using machine learning to better understand which lineup looking behaviors postdict suspect guilt., Hypotheses: We hypothesized that (a) lineups with guilty suspects would be subject to shorter viewing duration of all images and fewer image looks overall than lineups with innocent suspects, and (b) confidence and accuracy would be positively correlated. The question of which factors would combine to best postdict suspect guilt was exploratory. Experiment 1 included 405 children (6-14 years; 43% female) who each made 2 eyewitness identifications after viewing 2 live targets. Experiment 2 included 342 adult participants (Mage = 21.00; females = 75%) who each made 2 identifications after viewing a video including 2 targets. Participants made identifications using an interactive touchscreen simultaneous lineup in which they were restricted to viewing one image at a time and their interaction with the lineup was recorded. In Experiment 1, five variables (filler look time, suspect look time, number of suspect looks, number of filler looks, and winner look time) together postdicted (with a 67% accuracy score) target presence. In Experiment 2, four variables (number of suspect looks, number of filler looks, number of loser looks, and winner looks) together postdicted (with a 73% accuracy score) target presence. Further exploration of witness search behaviors can provide context to identification decisions. Understanding which behaviors postdict suspect guilt may assist with interpretation of identification decisions in the same way that decision confidence is currently used. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The Confidence-Accuracy Relationship Using Scale Versus Other Methods of Assessing Confidence

Historically, researchers have collected eyewitness identification confidence using scales; however, in practice, eyewitnesses are more commonly asked for a verbal statement. In Experiment 1, participants viewed a simultaneous lineup and provided confidence in their own words, by explaining why they made their decision or by selecting from statements made by real eyewitnesses, and then provided a scale rating (0–100%) or provided only the scale rating. In Experiment 2, participants viewed a sequential lineup and provided confidence in their own words followed by the scale rating or provided only the scale rating. Confidence predicted identification accuracy in all conditions, although verbal statements were highly variable and challenging to interpret. For example, only when scale-based confidence was high (80%+) did interpretation of the verbal confidence statement reliably align with scale-based confidence. These data highlight the complexity of verbal confidence statements and the need to establish meaningful boundaries for interpreting verbal confidence statements.

The number of fillers may not matter as long as they all match the description: The effect of simultaneous lineup size on eyewitness identification

SummaryAccording to the Diagnostic Feature‐Detection (DFD) hypothesis, the presence of fillers that match the eyewitness's description of the perpetrator will boost discriminability beyond a showup, and very few fillers may suffice to produce the advantage. We tested this hypothesis by comparing showups with simultaneous lineups of size 3, 6, 9, and 12. Participants (N = 10,433) were randomly assigned to one of these conditions, as well as target‐present (TP) versus target‐absent (TA) lineup. As predicted by the DFD hypothesis, lineups were superior to showups, and there was no advantage with increased lineup size beyond a 3‐member lineup. The confidence‐accuracy (CA) relationship held a similar pattern. The only effect of increased lineup size was a lower likelihood of choosing a suspect (guilty or innocent). We conclude that police should focus more on the quality rather than quantity of fillers.

Why are lineups better than showups? A test of the filler siphoning and enhanced discriminability accounts.

Presenting the police suspect alongside similar-looking people (a lineup) results in more accurate eyewitness identification decisions than presenting the suspect alone (a showup). Why are lineups better than showups? Diagnostic-feature-detection theory suggests that lineups enhance witnesses' ability to discriminate between innocent and guilty suspects, because facial features can be compared across lineup members. Filler-siphoning suggests that the presence of other lineup members siphons some of the incorrect identifications that would otherwise land on the innocent suspect. To test these 2 accounts, over 3,600 subjects across 3 experiments watched a mock-crime video and were presented with either a showup, a simultaneous lineup, or a simultaneous showup (a novel procedure). Subjects in the simultaneous showup condition saw the suspect and 5 similar-looking faces, but, unlike a lineup, could not identify the other faces. Presenting similar-looking faces alongside the suspect (simultaneous showup and lineup) enhanced subjects' ability to discriminate between innocent and guilty suspects compared with presenting the suspect alone (showup) as measured by Area Under the ROC Curve (pAUC) and fitting a signal-detection model. These results show, for the first time, that the discriminability advantage in simultaneous lineups is because of the comparison of multiple faces as predicted by diagnostic-feature-detection theory, but not the filler-siphoning account. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

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).

Lineup fairness: propitious heterogeneity and the diagnostic feature-detection hypothesis

Researchers have argued that simultaneous lineups should follow the principle of propitious heterogeneity, based on the idea that if the fillers are too similar to the perpetrator even an eyewitness with a good memory could fail to correctly identify him. A similar prediction can be derived from the diagnostic feature-detection (DFD) hypothesis, such that discriminability will decrease if too few features are present that can distinguish between innocent and guilty suspects. Our first experiment tested these predictions by controlling similarity with artificial faces, and our second experiment utilized a more ecologically valid eyewitness identification paradigm. Our results support propitious heterogeneity and the DFD hypothesis by showing that: 1) as the facial features in lineups become increasingly homogenous, empirical discriminability decreases; and 2) lineups with description-matched fillers generally yield higher empirical discriminability than those with suspect-matched fillers.

A method for increasing empirical discriminability and eliminating top‐row preference in photo arrays

SummaryIt is important to consider the two parameters of signal detection theory, discriminability and response bias, when evaluating eyewitness identification from simultaneous lineups. On the basis of the diagnostic feature‐detection hypothesis, we tested a method for increasing discriminability that encourages eyewitnesses to carefully rank each lineup member based on match to their memory for a perpetrator. This procedure increased empirical discriminability and also eliminated a response bias that is largely overlooked in the literature: Participants were biased to choose from the top row of the six‐pack (2 × 3) lineup commonly used in the United States. We argue that suspect position in the simultaneous lineup is an important variable to consider for researchers and the criminal justice system. We also encourage researchers to test the ranking procedure to determine if such a simple set of instructions could be utilized by police to help eyewitnesses correctly sort innocent versus guilty suspects.