Phenomenological reports diagnose accuracy of eyewitness identification decisions

This study investigated whether measuring the phenomenology of eyewitness identification decisions aids evaluation of their accuracy. Witnesses (N = 502) viewed a simulated crime and attempted to identify two targets from lineups. A divided attention manipulation during encoding reduced the rate of remember (R) correct identifications, but not the rates of R foil identifications or know (K) judgments in the absence of recollection (i.e., K/[1 − R]). Both RK judgments and recollection ratings (a novel measure of graded recollection) distinguished correct from incorrect positive identifications. However, only recollection ratings improved accuracy evaluation after identification confidence was taken into account. These results provide evidence that RK judgments for identification decisions function in a similar way as for recognition decisions; are consistent with the notion of graded recollection; and indicate that measures of phenomenology can enhance the evaluation of identification accuracy.     

Automaticity and eyewitness accuracy: a 10- to 12-second rule for distinguishing accurate from inaccurate positive identifications

Eyewitness researchers have shown that witnesses accurately choosing the culprit out of a lineup reach their decisions more quickly than those erroneously choosing an innocent individual. However, this research is silent regarding how quickly or slowly witnesses must be, in absolute terms, to indicate that they are accurate or inaccurate. Across 4 studies, the authors discovered that a time boundary of roughly 10 to 12 s best differentiated accurate from inaccurate positive identifications. Witnesses making their identification faster than 10 to 12 s were nearly 90% accurate; those taking longer were roughly 50% accurate. This finding is consistent with previous research showing that accurate witnesses are more likely than inaccurate witnesses to reach their decisions automatically, that is, quickly, without conscious thought or effort.     

Multiple confidence estimates as indices of eyewitness memory

Eyewitness identification decisions are vulnerable to various influences on witnesses' decision criteria that contribute to false identifications of innocent suspects and failures to choose perpetrators. An alternative procedure using confidence estimates to assess the degree of match between novel and previously viewed faces was investigated. Classification algorithms were applied to participants' confidence data to determine when a confidence value or pattern of confidence values indicated a positive response. Experiment 1 compared confidence group classification accuracy with a binary decision control group's accuracy on a standard old-new face recognition task and found superior accuracy for the confidence group for target-absent trials but not for target-present trials. Experiment 2 used a face mini-lineup task and found reduced target-present accuracy offset by large gains in target-absent accuracy. Using a standard lineup paradigm, Experiments 3 and 4 also found improved classification accuracy for target-absent lineups and, with a more sophisticated algorithm, for target-present lineups. This demonstrates the accessibility of evidence for recognition memory decisions and points to a more sensitive index of memory quality than is afforded by binary decisions.     

Effects of administrator-witness contact on eyewitness identification accuracy

Concern that lineup administrators can influence eyewitness identifications has led researchers to suggest implementing double-blind testing, an idea that police resist. Using a typical eyewitness paradigm (video event followed by photographic identification test), the present study demonstrated that an alternative technique, minimizing the level of contact between lineup administrators and witnesses, could reduce false identifications without reducing hits. Specifically, witnesses were more likely to make decisions consistent with lineup administrator expectations when the level of contact between the administrator and the witness was high than when it was low. These results are explained within the experimenter expectancy framework. Implications for applied settings are discussed.     

The effect of biased lineup instructions on eyewitness identification confidence

Although it is well‐known that biased lineup instructions (i.e., those that do not inform witnesses the perpetrator may not be in the lineup) inflate false identifications, their effects on witness confidence are less well understood due to methodological limitations of past studies. We report two studies that use novel methodologies to obviate these limitations. Study 1 (N = 177) demonstrated that biased lineup instructions increased witnesses' average estimates of the likelihood that a lineup member is guilty. Study 2 (N = 137) introduces a novel debiasing paradigm that allows a parsing of choosers into those who made an identification only because of the biased instructions (induced choosers), and those who would have chosen despite the instructions (inherent choosers). Biased lineup instructions inflated confidence only among induced choosers, but not among inherent choosers. Contrary to legal reasoning, witness confidence is an insufficient metric to determine the suggestiveness of biased instructions.     

Effects of postidentification feedback on eyewitness identification and nonidentification confidence

Two experiments investigated new dimensions of the effect of confirming feedback on eyewitness identification confidence using target-absent and target-present lineups and (previously unused) unbiased witness instructions (i.e., "offender not present" option highlighted). In Experiment 1, participants viewed a crime video and were later asked to try to identify the thief from an 8-person target-absent photo array. Feedback inflated witness confidence for both mistaken identifications and correct lineup rejections. With target-present lineups in Experiment 2, feedback inflated confidence for correct and mistaken identifications and lineup rejections. Although feedback had no influence on the confidence-accuracy correlation, it produced clear overconfidence. Confidence inflation varied with the confidence measure reference point (i.e., retrospective vs. current confidence) and identification response latency.     

Simultaneous independent threshold estimates: Multiple PEST

An adaptive threshold estimation procedure, PEST, has been extended to track sensitivity to many independent signals simultaneously within a single experimental run. This paradigm has been implemented on a PDP-8/S computer, and enables investigation of a number of otherwise experimentally intractible substantive problems. The logic of the new experimental paradigm is described, and some examples are given of its use in auditory research. Results of some computer simulations show the relative efficiency of the procedure and evaluate alternative ways to summarize data.     

Evolution of the empirical and theoretical foundations of eyewitness identification reform

Scientists in many disciplines have begun to raise questions about the evolution of research findings over time (Ioannidis in Epidemiology, 19, 640–648, 2008; Jennions & Møller in Proceedings of the Royal Society, Biological Sciences, 269, 43–48, 2002; Mullen, Muellerleile, & Bryan in Personality and Social Psychology Bulletin, 27, 1450–1462, 2001; Schooler in Nature, 470, 437, 2011), since many phenomena exhibit decline effects—reductions in the magnitudes of effect sizes as empirical evidence accumulates. The present article examines empirical and theoretical evolution in eyewitness identification research. For decades, the field has held that there are identification procedures that, if implemented by law enforcement, would increase eyewitness accuracy, either by reducing false identifications, with little or no change in correct identifications, or by increasing correct identifications, with little or no change in false identifications. Despite the durability of this no-cost view, it is unambiguously contradicted by data (Clark in Perspectives on Psychological Science, 7, 238–259, 2012a; Clark & Godfrey in Psychonomic Bulletin & Review, 16, 22–42, 2009; Clark, Moreland, & Rush, 2013; Palmer & Brewer in Law and Human Behavior, 36, 247–255, 2012), raising questions as to how the no-cost view became well-accepted and endured for so long. Our analyses suggest that (1) seminal studies produced, or were interpreted as having produced, the no-cost pattern of results; (2) a compelling theory was developed that appeared to account for the no-cost pattern; (3) empirical results changed over the years, and subsequent studies did not reliably replicate the no-cost pattern; and (4) the no-cost view survived despite the accumulation of contradictory empirical evidence. Theories of memory that were ruled out by early data now appear to be supported by data, and the theory developed to account for early data now appears to be incorrect.     

Remembering a criminal conversation: beyond eyewitness testimony

Unlike the important body of work on eyewitness memory, little research has been done on the accuracy and completeness of "earwitness" memory for conversations. The present research examined the effects of mode of presentation (audiovisual/ auditory-only) on witnesses' free recall for utterances in a criminal conversation at different retention intervals (immediate/delayed) within a single experiment. Different forms of correct recall (verbatim/gist) of the verbal information as well as different types of errors (distortions/fabrications) were also examined. It was predicted that participants in the audiovisual modality would provide more correct information, and fewer errors than participants in the auditory-only modality. Participants' recall was predicted to be impaired over time, dropping to a greater extent after a delay in the auditory-only modality. Results confirmed these hypotheses. Interpretations of the overall findings are offered within the context of dual-coding theory, and within the theoretical frameworks of source monitoring and fuzzy-trace theory.     

The effects of local and global processing orientation on eyewitness identification performance

Recent work has demonstrated that performance on a simultaneous target-present photographic line-up can be enhanced by prior global processing orientation, and hindered by prior local processing orientation induced by processing Navon letter stimuli. A series of studies explore the generality of this processing bias effect using either videotaped scenarios or live interactions. Five experiments demonstrate that these effects are seen across a range of test stimuli, test formats, and test instructions.These data inform the processes engaged in by witnesses when making line-up identifications and indicate that it may be possible to improve the accuracy of witnesses making such judgements.     

Intended and unintended effects of explicit warnings on eyewitness suggestibility: Evidence from source identification tests

Previous studies have shown that source identification (ID) tests reduce, and in some cases eliminate, eyewitness suggestibility errors. The present study showed that the suggestibility errors participants committed on a source ID test were further reduced when they were given the explicit postwarning that the experimenter was trying to trick them. These postwarnings reduced suggestibility to the same extent as prewarnings, and they did so for both once and repeatedly suggested items. In addition, the benefits of the pre- and postwarnings persisted when participants were retested 1 week later, but only if the suggestions had been repeated. For once-suggested items, the warning had the unintended effect of improving old/new recognition of the suggested information at retest, an effect that offset the improvements in source discrimination accuracy conferred by the warning. The advantages of using source ID tests for investigating group differences in eyewitness suggestibility are discussed.     

Emotional stress and eyewitness memory: a critical review.

The eyewitness literature often claims that emotional stress leads to an impairment in memory and, hence, that details of unpleasant emotional events are remembered less accurately than details of neutral or everyday events. A common assumption behind this view is that a decrease in available processing capacity occurs at states of high emotional arousal, which, therefore, leads to less efficient memory processing. The research reviewed here shows that this belief is overly simplistic. Current studies demonstrate striking interactions between type of event, type of detail information, time of test, and type of retrieval information. This article also reviews the literature on memory for stressful events with respect to two major theories: the Yerkes-Dodson law and Easter-brook's cue-utilization hypothesis. To account for the findings from real-life studies and laboratory studies, this article discusses the possibility that emotional events receive some preferential processing mediated by factors related to early perceptual processing and late conceptual processing.     

The confidence-accuracy relationship in eyewitness identification: the effects of reflection and disconfirmation on correlation and calibration

Participants viewed a simulated crime and attempted an identification from an 8-person target-present or target-absent lineup. The authors examined identification confidence-accuracy relations, contrasting a control condition (n = 310) with 2 manipulations designed to improve confidence scaling. Before indicating confidence, participants reflected on encoding and identification test conditions (n = 316) or suggested hypotheses about why their identification decision might have been wrong (n = 318). Confidence-accuracy correlations were weak and did not differ across conditions. However, for positive identifications, confidence and accuracy were well calibrated in the experimental conditions, although not in the control condition; similar patterns were observed for lineup rejections. Explanations for calibration differences in terms of discrimination difficulty, (mis)match between encoding and test stimuli, and the availability of confidence cues were advanced.     

A method for calibrating the spatial coordinates of a visual display to high accuracy

High-resolution CRT displays are subject togeometric distortion: lines that are straight in the internal coordinates of the graphics software and hardware are curved when projected onto a plane in the observer’s line of sight. As the available resolution of CRT screens increases, it becomes more difficult to measure and correct for this distortion. We present a simple, highly accurate method for determining the mapping between internal coordinates and the viewing plane. It requires that an observer, using a calibration program, adjust triples of displayed points until they are collinear. A metal straightedge placed between the observer and the screen aids in this judgment. We describe the calibration of an IBM Enhanced Graphics Display in high-resolution mode (350 × 640 pixels), and illustrate how to use the estimated mapping to choose internal coordinates to draw undistorted figures that are accurate to within 0.5 pixel. The method can be used to assess or to correct the accuracy of visual displays. The method is relevant to experiments in spatial vision, spatial perception, perception of dot patterns, and any application in which geometrically accurate stimuli are required.     

Thurstonian-type representations for “same-different” discriminations: Deterministic decisions and independent images

A discrimination probability function obtained in the “same-different” paradigm assigns to every ordered pair of stimuli the probability with which they are judged to be different. This function is said to possess the regular minimality property if, for any stimulus pair ,

     

The confidence-accuracy relationship in eyewitness identification: effects of lineup instructions, foil similarity, and target-absent base rates

Discriminating accurate from mistaken eyewitness identifications is a major issue facing criminal justice systems. This study examined whether eyewitness confidence assists such decisions under a variety of conditions using a confidence-accuracy (CA) calibration approach. Participants (N = 1,200) viewed a simulated crime and attempted 2 separate identifications from 8-person target-present or target-absent lineups. Confidence and accuracy were calibrated for choosers (but not nonchoosers) for both targets under all conditions. Lower overconfidence was associated with higher diagnosticity, lower target-absent base rates, and shorter identification latencies. Although researchers agree that courtroom expressions of confidence are uninformative, our findings indicate that confidence assessments obtained immediately after a positive identification can provide a useful guide for investigators about the likely accuracy of an identification.     

Utilization of context for word identification decisions in children

The use of context was investigated with subjects from fourth- and sixth-grade populations. A Word Boundary task was used that requires subjects to make word-identification decisions both with and without contextual information. Results indicated that context was utilized effectively by the sixth-grade students, while the fourth-grade students showed small context-use effects. These findings are consistent with performance models that emphasize the role of predictive behavior in language analysis.     

The damaging effect of confirming feedback on the relation between eyewitness certainty and identification accuracy

The authors investigated eyewitnesses' retrospective certainty (see G. L. Wells & A. L. Bradfield, 1999). The authors hypothesized that extemal influence from the lineup administrator would damage the certainty-accuracy relation by inflating the retrospective certainty of inaccurate eyewitnesses more than that of accurate eyewitnesses (N = 245). Two variables were manipulated: eyewitness accuracy (through the presence or absence of the culprit in the lineup) and feedback (confirming vs. control). Confirming feedback inflated retrospective certainty more for inaccurate eyewitnesses than for accurate eyewitnesses, significantly reducing the certainty-accuracy relation (from r = .58 in the control condition to r = .37 in the confirming feedback condition). Double-blind testing is recommended for lineups to prevent these external influences on eyewitnesses.