Memory for murder. A psychological perspective on dissociative amnesia in legal contexts.

There is currently a complex and inconsistent state in the law relating to dissociation and dissociative amnesia (McSherry, 1998). Although dissociative amnesia in defendants is relevant to both competency to stand trial and criminal responsibility in principle, courts have typically assumed a skeptical stance toward such claims in practice. However, there is considerable evidence from both nonoffender and offender populations to support the validity of dissociative amnesia in defendants. Further, there is information available to aid in the evaluation of amnesia, such as the quality of the report itself and characteristics of the person reporting the amnesia (e.g., psychopathy). When consideration is given to the legal response to reports of dissociative amnesia by complainants, the situation becomes even more complex. While some courts have rejected recovered memory evidence, others have convicted defendants of historical offenses based on such evidence. In some cases, judges have argued that jurors should be left to decide on the validity of recovered memories based on their common sense and experience. The uncritical acceptance of the validity of repressed memories in complainants by many courts stands in stark contrast to the response to claims of amnesia from defendants. It seems apparent that the courts need better guidelines around the issue of dissociative amnesia in both populations. We think that the increasing scientific understanding of memory in the past decade (see Schacter, 1999) can meaningfully contribute to the development of such guidelines. Responsible, nonpartisan expert testimony from mental health professionals would be one step in the direction of rectifying the current state of law in regards to dissociation.

Negotiating false memories: interviewer and rememberer characteristics relate to memory distortion.

In a recent study, more than half of the participants were led to create a partial or complete false memory for an emotional childhood event (e.g., serious animal attack). Using a subsample from that study, we examined the hypothesis that memory distortion is related to characteristics of interviewers and rememberers. The relations between susceptibility to memory distortion and (a) dissociation (Dissociative Experiences Scale) and (b) personality traits (NEO-Five Factor Inventory) were investigated. Results indicated that participants who exhibited memory distortion scored significantly higher on the dissociative scale than their counterparts who did not exhibit memory distortion. Further, susceptibility to memory distortion was associated with higher extraversion scores in interviewers and lower extraversion scores in participants. This pattern of findings suggests that false memories may derive from a social negotiation between particular interviewers and rememberers.

The nature of real, implanted, and fabricated memories for emotional childhood events: implications for the recovered memory debate.

A central issue in the recovered memory debate is whether it is possible to "remember" a highly emotional incident which never occurred. The present study provided an in-depth investigation of real, implanted, and fabricated (deceptive) memories for stressful childhood events. We examined whether false memories for emotional events could be implanted and, if so, whether real, implanted, and fabricated memories had distinctive features. A questionnaire was sent to participants' parents asking about six highly emotional, stressful events (e.g., serious animal attack) which the participant may have experienced in childhood. Next, across three sessions, interviewers encouraged participants (N = 77) to "recover" a memory for a false event using guided imagery and repeated retrieval attempts. In the first interview, they were asked about one real and one false event, both introduced as true according to their parents. In two subsequent interviews, they were reinterviewed about the false event. Finally, after the third inquiry about the false event, participants were asked to fabricate a memory report. Results indicated that 26% of participants "recovered" a complete memory for the false experience and another 30% recalled aspects of the false experience. Real, implanted, and fabricated memories differed on several dimensions (e.g., confidence, vividness, details, repeated details, coherence, stress). These findings have important implications for the debate over recovered and false memories.

Anatomically-neutral dolls: their effects on the memory and suggestibility of 4- to 6-year-old eyewitnesses.

The purpose of this investigation was to compare the amount and accuracy of details provided in the eyewitness accounts of preschool-aged children interviewed exclusively with a verbal interview against those interviewed with anatomically-neutral dolls in addition to a verbal interview. Forty-four children, aged 4 to 6 years, were paired up and assigned as participants or observers for an event they engaged in with a confederate. Children's memory was assessed afterwards by (a) The Step-Wise Interview (Yuille, Hunter, Joffe, & Zaparniuk, 1993); (b) the Step-Wise Interview and big dolls; or (c) The Step-Wise Interview and small, detailed dolls and props. Three leading questions were incorporated into the interviews. Results indicated no main effect of interview type on the overall amount or accuracy of the children's accounts. No main effects for interview type or participant versus observer condition were observed for the leading questions. Relative to 4-year-olds, 5-year-olds recalled a greater number of overall details and were more accurate in their accounts with both types of dolls. Females were more accurate than males in their accounts with the small detailed toys and props. Implications for the use of anatomically-neutral dolls in child sexual abuse investigations are discussed.

A comparison of the eyewitness accounts of deaf and hearing children.

Children with hearing impairments have been found to suffer a high rate of physical and sexual victimization relative to children in general. The purpose of this investigation was to compare the amount and accuracy of the information contained in the eyewitness accounts of deaf and hearing children. Fifteen deaf and 11 hearing children, aged 8 to 10 years, individually witnessed a series of slides depicting a wallet theft. Their recall was then tested by using the Step-Wise Interview (Yuille, Hunter, Joffe, & Zaparniuk, 1993) consisting of a free recall component followed by increasingly directive questions. Separate 2 x 2 (deaf/hearing x question type) between-within factorial ANOVAs were conducted on the amount and accuracy of the information in the accounts (A = .025). Results indicated no main or interaction effects for amount recalled. However, a main effect for question type and an interaction effect were evidenced in the analysis on accuracy. Although the accuracy scores of the two groups did not differ in free recall, the deaf children provided much less accurate responses to directive questions whereas the accuracy of the hearing children declined only slightly. Implications for criminal investigations are discussed.

Should this child be removed from home? Hypothesis generation and information seeking as predictors of case decisions.

Two vital aspects of the investigative process in child abuse and neglect (CAN) cases are (a) generating as many plausible hypotheses as possible and (b) seeking out as much uncontaminated information as possible. Alternatively, unwarranted assumptions about the nature of CAN cases can impair investigative decision making. We examined whether the numbers of (a) unwarranted assumptions, (b) hypotheses generated, and (c) requests for additional information concerning a hypothetical reported case of CAN predicted level of agreement with a premature decision to remove a child from home among a group of CAN professionals. As expected, lower levels of agreement with the intervention were associated with (a) less unwarranted assumptions, (b) a greater number of hypotheses generated, and (c) more requests for information concerning the case. Compared with a group of undergraduates, a significantly greater percentage of CAN professionals requested information, and a significantly smaller percentage of professionals made unwarranted assumptions. Interestingly, however, no significant difference in mean level of agreement with the intervention was observed between professionals and undergraduates. Directions for future research are discussed.

Alcohol and the physiological detection of deception: arousal and memory influences.

Eighty male volunteers participated in an analogue study of the effects of alcohol intoxication at the time of a crime on the physiological detection of deception using control question and guilty knowledge techniques. Sixty-four of the subjects committed a mock crime and half of these were intoxicated during the crime. Sixteen subjects committed no crime and served as innocent controls. We found that intoxication at the time of the crime had no significant effect on polygraph test outcomes, although it did affect anticipatory arousal before the crime and subsequent memory for crime details. Manipulations designed to influence memory for crime details and arousal during the crime had differential effects for the two polygraph tests. On the guilty knowledge test, primed subjects who rehearsed specific details following the crime were more detectable than unprimed subjects. On the control question test, primed subjects were also more detectable, but only when arousal during the crime was high.

Lost but not forgotten details: repeated eyewitness recall leads to reminiscence but not hypermnesia.

In 2 experiments, the effects on participants' memory and confidence of repeatedly describing a videotaped crime and of the opportunity to review a previous description were investigated. E. Scrivner and M. A. Safer (1988) demonstrated that witnesses' successive attempts to describe such events can lead to the recall of more new information in comparison with the amount forgotten (i.e., increased net recall, or hypermnesia). In Experiment 1, a more forensically relevant procedure was used, and no support for hypermnesia was found. Witnesses did recall significantly more new information across attempts, but the amount did not exceed how much was forgotten (i.e., increased gross recall, or reminiscence). The opportunity to review a previous statement had no effect on the number of items recalled. In Experiment 2, the more traditional, repeated-recall procedure used by Scrivner and Safer was applied, and their finding of hypermnesia was replicated with the present study's materials.

Some effects of alcohol on eyewitness memory.

Male volunteers (N = 120) in small groups of 5 to 10 watched a staged theft involving live actors. Some (n = 47) were under the influence of alcohol (average blood alcohol level of .10) at the time. Some subjects (n = 58) were interviewed immediately after the event, and all were interviewed 1 week later. The delayed interview included the presentation of a photospread that either did or did not contain the picture of the "thief." Alcohol suppressed the amount recalled during the immediate interview and both the amount and accuracy of recall after the 1-week delay. Alcohol had no influence on the ability of witnesses to recognize the thief's picture. When the thief's picture was not present in the photospread, however, alcohol increased the rate of false identifications. An immediate interview substantially improved the amount of information subjects were able to recall 1 week later.