Lineup identification accuracy: the effects of alcohol, target presence, confidence ratings, and response time

Despite the intoxication of many eyewitnesses at crime scenes, only four published studies to date have investigated the effects of alcohol intoxication on eyewitness identification performance. While one found intoxication significantly increased false identification rates from target absent showups, three found no such effect using the more traditional lineup procedure. The present study sought to further explore the effects of alcohol intoxication on identification performance and examine whether accurate decisions from intoxicated witnesses could be postdicted by confidence and response times. One hundred and twenty participants engaged in a study examining the effects of intoxication (control, placebo, and mild intoxication) and target presence on identification performance. Participants viewed a simultaneous lineup one week after watching a mock crime video of a man attempting to steal cars. Ethanol intoxication (0.6 ml/kg) was found to make no significant difference to identification accuracy and such identifications from intoxicated individuals were made no less confidently or slowly than those from sober witnesses. These results are discussed with respect to the previous research examining intoxicated witness identification accuracy and the misconceptions the criminal justice system holds about the accuracy of such witnesses.

The Impact of the "Not Sure" Option on Lineup Identification Decisions

Law enforcement officials routinely rely on eyewitness identification evidence to solve crimes. Nonetheless, this form of evidence is prone to errors. Researchers have previously attempted to examine conditions under which such errors can be reduced. The present study examines whether giving witnesses an explicit not sure response option increases the accuracy of lineup identification decisions. 251 participants watched a mock crime video before viewing a lineup that either included the perpetrator, or was made up of innocent suspects. Results indicated that witnesses provided with a not sure option made fewer false identifications, fewer filler identifications, and a similar number of correct identifications as witnesses who were not provided with this option. Furthermore, these benefits occurred regardless of whether witnesses received otherwise biased or unbiased instructions. Results suggest that the inclusion of an explicit not sure response option is a simple procedure that can increase the quality of eyewitness lineup decisions.

Memory conformity: Actors and bystanders

This dissertation explored memory conformity effects on people who interacted with a confederate and of bystanders to that interaction. Two studies were carried out. Study 1 was conducted in the field. A male confederate approached a group of people at the beach and had a brief interaction. About a minute later a research assistant approached the group and administered a target-absent lineup to each person in the group. Analyses revealed that memory conformity occurred during the lineup task. Bystanders were twice as likely to conform as those who interacted with the confederate. Study 2 was carried out in a laboratory under controlled conditions. Participants were exposed to two events during their time in the laboratory. In one event, participants were shown a brief video with no determinate roles assigned. In the other event participants were randomly assigned to interact with a confederate (actor condition) or to witness that interaction (bystander condition). Participants were given memory tests on both events to understand the effects of participant role (actor vs. bystander) on memory conformity. Participants answered second to all questions, following a confederate acting as a participant, who disseminated misinformation on critical questions. Analyses revealed no significant differences in memory conformity between actors and bystanders during the movie memory task. However, differences were found for the interaction memory task such that bystanders conformed more than actors on two of four critical questions. Bystanders also conformed more than actors during a lineup identification task. The results of these studies suggest that the role a person plays in an interaction affects how susceptible they are to information from a co-witness. Theoretical and applied implications are discussed. First, the results are explained through the use of two models of memory. Second, recommendations are made for forensic investigators.

Eyewitness decision -making with showups: Probative or perilous?

Showups are a technique of eyewitness identification in which a single suspect is presented to a witness for identification. Showups are controversial. Defense attorneys argue that they are suggestive and place suspects at undue risk of false identification. Prosecutors and police officers argue that showups are an indispensable investigative tool and are no more suggestive than other identification techniques. Are showups probative or perilous? If so, what can be done to improve their accuracy? This investigation converged on this question by addressing three interrelated goals. The first was to examine the effect of two system variables, retention interval and suspect clothing, on showup accuracy. The second was to determine if showups are more suggestive than lineups. The third goal was to explore carryover effects from showups to subsequent lineup identifications. ^ Eyewitness performance was evaluated with the Eyewitness Identification Paradigm. Approximately 500 undergraduate students at FIU witnesses a staged event (i.e., a "crime") in their classrooms and subsequently participated in a showup and/or lineup identification test. Half of the identification tests contained the target (i.e., the "perpetrator") and half contained a target-substitute (i.e., an "innocent suspect"). ^ The results of this study indicated that, overall, showups are not unusually prejudicial and are no more suggestive than lineups. However this study identified two specific conditions under which showups are likely to lead to false identifications of an innocent suspect. First, false identification are likely to occur in showups that are conducted shortly after a crime when the suspect is wearing clothing similar to that worn by the perpetrator. Second, placing an innocent suspect in both a showup and then a lineup substantially increases the chances that the suspect will be falsely identified in the lineup. The implications of these findings for the conduct of eyewitness investigations are discussed. ^

Does expert psychological testimony improve juror sensitivity to lineup suggestiveness?

Previous research has examined the validity of behavioral assumptions underlying the presumed effectiveness of safeguards against erroneous conviction resulting from mistaken eyewitness identification. In keeping with this agenda, this study examined juror sensitivity to lineup suggestiveness in the form of foil, instruction, and presentation biases and whether expert psychological testimony further sensitizes jurors to the factors that influence the likelihood of false identifications. One hundred and sixty jury eligible citizens watched versions of a videotaped trial that included information about the identification of the defendant by an eyewitness and that varied the suggestiveness of the eyewitness identification procedure. In addition, half of the mock-jurors heard the testimony of an expert psychologist regarding the factors that influence lineup suggestiveness. Mock-jurors rendered individual verdicts, rated the defendant's culpability and the suggestiveness and fairness of the identification procedure. Results indicated that jurors are somewhat sensitive to foil bias but are insensitive to instruction and presentation biases. No evidence was found to suggest that expert testimony leads to juror skepticism or juror sensitization. These results question the effectiveness of cross-examination and expert testimony as safeguards against erroneous convictions resulting from mistaken identification. ^

How effective is the motion-to -suppress safeguard? Judges' perceptions of the suggestiveness and fairness of biased lineup procedures

The motion-to-suppress safeguard is designed to prevent false eyewitness identifications from leading to wrongful convictions. This safeguard is effective only if judges are sensitive to factors that influence lineup suggestiveness. The present study assessed judicial sensitivity to foil, instruction, and presentation biases. Judges $(N=99)$ read a description of a hypothetical crime, perpetrator, and identification procedure, followed by a motion to suppress the identification. Judges completed a questionnaire in which they ruled on the motion and rated the lineup's suggestiveness and fairness. Foil bias and instruction bias influenced judges' rulings and lineup evaluations as predicted. Hypotheses concerning presentation bias were not supported. Results suggest a need to standardize and record identification procedures and to further educate judges about psychological research on eyewitness memory. ^

A theoretical analysis of eyewitness identification: Dual -process theory, signal detection theory and eyewitness confidence

Given the growing number of wrongful convictions involving faulty eyewitness evidence and the strong reliance by jurors on eyewitness testimony, researchers have sought to develop safeguards to decrease erroneous identifications. While decades of eyewitness research have led to numerous recommendations for the collection of eyewitness evidence, less is known regarding the psychological processes that govern identification responses. The purpose of the current research was to expand the theoretical knowledge of eyewitness identification decisions by exploring two separate memory theories: signal detection theory and dual-process theory. This was accomplished by examining both system and estimator variables in the context of a novel lineup recognition paradigm. Both theories were also examined in conjunction with confidence to determine whether it might add significantly to the understanding of eyewitness memory. ^ In two separate experiments, both an encoding and a retrieval-based manipulation were chosen to examine the application of theory to eyewitness identification decisions. Dual-process estimates were measured through the use of remember-know judgments (Gardiner & Richardson-Klavehn, 2000). In Experiment 1, the effects of divided attention and lineup presentation format (simultaneous vs. sequential) were examined. In Experiment 2, perceptual distance and lineup response deadline were examined. Overall, the results indicated that discrimination and remember judgments (recollection) were generally affected by variations in encoding quality and response criterion and know judgments (familiarity) were generally affected by variations in retrieval options. Specifically, as encoding quality improved, discrimination ability and judgments of recollection increased; and as the retrieval task became more difficult there was a shift toward lenient choosing and more reliance on familiarity. ^ The application of signal detection theory and dual-process theory in the current experiments produced predictable results on both system and estimator variables. These theories were also compared to measures of general confidence, calibration, and diagnosticity. The application of the additional confidence measures in conjunction with signal detection theory and dual-process theory gave a more in-depth explanation than either theory alone. Therefore, the general conclusion is that eyewitness identifications can be understood in a more complete manor by applying theory and examining confidence. Future directions and policy implications are discussed. ^

LINEUP SIZE AND NUMBER OF CUES: WHEN BIGGER ISN’T BETTER

Larger lineups could protect innocent suspects from being misidentified; however, they can also decrease correct identifications. Bertrand (2006) investigated whether the decrease in correct identifications could be prevented by adding more cues, in the form of additional views of lineup members’ faces, to the lineup. Adding these cues was successful to an extent. The current series of studies attempted to replicate Bertrand’s (2006) findings while addressing some methodological issues—namely, the inconsistency in image size as lineup size increased. First, I investigated whether image size could affect face recognition (Chapter 2) and found it could, but that it also affected previously-seen (“old”) versus previously-unseen (“new”) faces differently. Specifically, smaller image sizes at exposure lowered accuracy for old faces, while these same image sizes at recognition lowered accuracy for new faces. Although these results indicate that target recognition would be unaffected by image size at recognition (i.e., during a lineup), lineups are also comprised of previously-unseen faces, in the form of fillers and innocent suspects. Because image size could affect lineup decisions, as it could become more difficult to realize fillers are previously-unseen, I decided to replicate Bertrand (2006) while keeping image size constant in Chapters 3 (simultaneous lineups) and 4 (simultaneous-presentation, sequential decisions). In both Chapters, the integral findings were the same: correct identification rates decreased as lineup size increased from 6- to 24-person lineups, but adding cues had no effect. The inability to replicate Bertrand (2006) could mean that the original finding was due to chance, but alternate explanations also exist, such as the overall size of the array, the degree to which additional cues overlap, and the length of the target exposure. These alternate explanations, along with directions for future research, are discussed in the following Chapters.

Texture for Script identification

The problem of determining the script and language of a document image has a number of important applications in the field of document analysis, such as indexing and sorting of large collections of such images, or as a precursor to optical character recognition (OCR). In this paper, we investigate the use of texture as a tool for determining the script of a document image, based on the observation that text has a distinct visual texture. An experimental evaluation of a number of commonly used texture features is conducted on a newly created script database, providing a qualitative measure of which features are most appropriate for this task. Strategies for improving classification results in situations with limited training data and multiple font types are also proposed.