Claims of crime-related amnesia in forensic patients

Forensic neuropsychological assessment

With its firm establishment as a neuropsychology subspecialty, forensic neuropsychological assessment is integral to many criminal and civil forensic evaluations. In addition to evaluating cognitive deficits, forensic neuropsychologists can provide reliable information regarding symptom magnification, malingering, and other neurocognitive and psychological issues that may impact the outcome of a particular legal case. This article is an overview and introduction to neuropsychological assessment in the forensic mental health context. Major issues impacting the current practice of forensic neuropsychology are summarized, and several examples from case law are highlighted.

Ruling out feigned crime-related amnesia? A response to Acklin (2022)

In a recent paper, Acklin discussed a case of possible amnesia for a murder in terms of neurobiology, psychoanalysis, and personality assessment. Acklin accepted the defendant's claim of amnesia for the crime as genuine. The considerable literature that takes a skeptical view of crime-related amnesia was not cited, and the possibility of feigning or malingering was "ruled out" with a single sentence that does not withstand scrutiny. A review of the literature on feigned amnesia suggests that it may not be possible to rule out malingering even if the best available tools are used: There has been minimal investigation of most validity tests and estimates of base rates of feigned amnesia for a crime vary widely and make estimates of Negative Predictor Power highly unreliable. Although one cannot know from the information presented if Acklin's defendant legitimately experienced amnesia, feigning could not be ruled out using an interview and the test data cited by Acklin. I call for a moratorium on publication of further articles on crime specific amnesia that do not conscientiously examine other potential explanations and do not use current best practices for assessing negative response bias.

The Memory-Undermining Effect of Simulated Crime-Related Amnesia and Its Legal Implications: a Review

Pretending to suffer from amnesia for a mock crime has been shown to lead to memory impairments. Specifically, when people are asked to give up their role of simulators, they typically recall fewer crime-relevant details than those who initially confess to a crime. In the current review, we amassed all experimental work on this subject and assessed the characteristics of the memory-undermining effect of simulated amnesia for a crime procedure (i.e., crime stimuli, simulating amnesia instructions, memory tests, and memory outcomes). We specifically focused on the effect that crime-related amnesia claims may have on offenders’ final memory reports. Our review showed that simulators who initially claimed amnesia might paradoxically experience some sort of forgetting pertaining to crime-related information. This issue could likely lead to legal complications that need be taken into account in crime-related amnesia cases.

The Detection of Malingered Amnesia: An Approach Involving Multiple Strategies in a Mock Crime

The nature of amnesia in the context of crime has been the subject of a prolonged debate. It is not uncommon that after committing a violent crime, the offender either does not have any memory of the event or recalls it with some gaps in its recollection. A number of studies have been conducted in order to differentiate between simulated and genuine amnesia. The recognition of probable malingering requires several inferential methods. For instance, it typically involves the defendant's medical records, self-reports, the observed behavior, and the results of a comprehensive neuropsychological examination. In addition, a variety of procedures that may detect very specific malingered amnesia in crime have been developed. In this paper, we investigated the efficacy of three techniques, facial thermography, kinematic analysis, and symptom validity testing in detecting malingering of amnesia in crime. Participants were randomly assigned to two different experimental conditions: a group was instructed to simulate amnesia after a mock homicide, and a second group was simply asked to behave honestly after committing the mock homicide. The outcomes show that kinematic analysis and symptom validity testing achieve significant accuracy in detecting feigned amnesia, while thermal imaging does not provide converging evidence. Results are encouraging and may provide a first step towards the application of these procedures in a multimethod approach on crime-specific cases of amnesia.

Feigning Amnesia Moderately Impairs Memory for a Mock Crime Video

Previous studies showed that feigning amnesia for a crime impairs actual memory for the target event. Lack of rehearsal has been proposed as an explanation for this memory-undermining effect of feigning. The aim of the present study was to replicate and extend previous research adopting a mock crime video instead of a narrative story. We showed participants a video of a violent crime. Next, they were requested to imagine that they had committed this offense and to either feign amnesia or confess the crime. A third condition was included: Participants in the delayed test-only control condition did not receive any instruction. On subsequent recall tests, participants in all three conditions were instructed to report as much information as possible about the offense. On the free recall test, feigning amnesia impaired memory for the video clip, but participants who were asked to feign crime-related amnesia outperformed controls. However, no differences between simulators and confessors were found on both correct cued recollection or on distortion and commission rates. We also explored whether inner speech might modulate memory for the crime. Inner speech traits were not found to be related to the simulating amnesia effect. Theoretical and practical implications of our results are discussed.

What Do People Believe About Memory? Implications for the Science and Pseudoscience of Clinical Practice

We examine the evidence concerning what people believe about memory. We focus on beliefs regarding the permanence of memory and whether memory can be repressed and accurately recovered. We consider beliefs about memory among the undergraduate and general population, mental health professionals, judges, jurors, and law enforcement officers to provide a broad canvass that extends to the forensic arena, as well as to psychiatry, psychology, and allied disciplines. We discuss the implications of these beliefs for the education of the general public and mental health professionals regarding the science and pseudoscience of memory and the use of suggestive procedures in psychotherapy.

False memories for aggressive acts

Can people develop false memories for committing aggressive acts? How does this process compare to developing false memories for victimhood? In the current research we used a simple false feedback procedure to implant false memories for committing aggressive acts (causing a black eye or spreading malicious gossip) or for victimhood (receiving a black eye). We then compared these false memories to other subjects' true memories for equivalent events. False aggressive memories were all too easy to implant, particularly in the minds of individuals with a proclivity towards aggression. Once implanted, the false memories were indistinguishable from true memories for the same events, on several dimensions, including emotional content. Implications for aggression-related memory more generally as well as false confessions are discussed.

Alcohol-induced blackout as a criminal defense or mitigating factor: an evidence-based review and admissibility as scientific evidence

Alcohol-related amnesia--alcohol blackout--is a common claim of criminal defendants. The generally held belief is that during an alcohol blackout, other cognitive functioning is severely impaired or absent. The presentation of alcohol blackout as scientific evidence in court requires that the science meets legal reliability standards (Frye, FRE702/Daubert). To determine whether "alcohol blackout" meets these standards, an evidence-based analysis of published scientific studies was conducted. A total of 26 empirical studies were identified including nine in which an alcohol blackout was induced and directly observed. No objective or scientific method to verify the presence of an alcoholic blackout while it is occurring or to confirm its presence retrospectively was identified. Only short-term memory is impaired and other cognitive functions--planning, attention, and social skills--are not impaired. Alcoholic blackouts would not appear to meet standards for scientific evidence and should not be admissible.

Let's use those tests! Evaluations of crime-related amnesia claims

Suspects awaiting trial often claim that they cannot remember important parts of their violent crimes. It is not unusual that forensic experts readily accept such claims and interpret them in terms of dissociative amnesia or, more specifically, a "red-out". This interpretation hinges on the assumption that heightened levels of stress implicated in violent crimes interfere with memory. We argue that the notion of red-out is a priori not plausible and that alternative interpretations-primarily malingering and substance-induced organic amnesia-should be considered and ruled out first before concluding that memory loss is dissociative in nature. We illustrate our point with four cases that superficially have the contours of red-out tragedies. We believe that, in such cases, neuropsychological tests and/or psychopharmacological information on dose-response relationships can assist forensic experts to exclude malingering or substance-induced amnesia. There is no reason for not using tests and tools from neuropsychology and psychopharmacology.

Homicidal behaviour among people with avoidant, dependent and obsessive-compulsive (cluster C) personality disorder

BACKGROUND

Despite a growing forensic psychiatry literature, no previous study has examined in detail homicidal behaviour among offenders with cluster C personality disorders - the avoidant, dependent or obsessional personality disorders.

AIMS

This study aims to compare homicide offenders with cluster C personality disorders with those with other personality disorders on criminal history, offender-victim relationship and post-offence reaction variables.

METHODS

The sample was drawn from all Finnish homicide cases of 1996-2004 for whom a forensic psychiatric evaluation had been conducted. Data were extracted from forensic psychiatric and crime reports.

RESULTS

In a nationwide sample of 593 homicide offenders, 21 had at least one cluster C personality disorder. These offenders had significantly shorter criminal histories than the others. Offender-victim relationship did not differ between the groups, but confession to the crime and feelings of remorse were more common among people with cluster C disorders. In addition, compared with other personality disorder clusters, co-morbid depression was more common.

CONCLUSIONS

Cluster C personality disorders are rare, but not nonexistent, among homicide offenders. Observed differences in their backgrounds and post-offence behaviours indicate that they may have special needs.

Evaluating amnesia for criminal behavior: a guide to remember

This article provides a guide that is important to remember in evaluating a criminal defendant's amnesia claim. Important concepts to understand regarding memory formation, memory systems, proposed causes of amnesia, reasons why amnesia claims may be true or false, and important strategies to implement as part of the evaluation process are reviewed. Structured assessment approaches are critical components of amnesia evaluations and generally require detailed questioning, review of collateral records, medical and neurologic workups, psychological testing, neuropsychological testing, and specific malingering assessments.

A study of amnesia in homicide cases and forensic psychiatric experts' examination of such claims

About one third of defendants in homicide cases claim amnesia during the time of their alleged act. Examining the authenticity of claimed amnesia is a special challenge for forensic experts. Because the experts' conclusions have legal implications, it is useful to study the characteristics of defendants who claim amnesia regarding a homicidal act and how forensic experts assess these defendants' claims. The forensic psychiatric reports from 2001 to 2007 on 102 Norwegian defendants charged with homicide were assessed quantitatively with a structured rating form. Due to multiple comparisons p of .003 was chosen. Twenty-six defendants claimed partial and 17 claimed total amnesia. No significant differences in the characteristics of the defendants were found between the partial, total, and no amnesia claiming groups. Claims of partial or total amnesia did not change the procedures and content of the forensic experts' examination. A memory test was applied in only one case. Despite the seriousness of the crime and the difficulty of assessing amnesia, the experts did not apply psychological testing of memory function or appropriate tests of possible malingering. Guidelines or standardized procedures for evaluation of defendants who claim amnesia should be developed. This could eventually contribute to more reliable and valid evaluations by forensic experts and increase the probability of just court outcomes.

A comparison of memory for homicide, non-homicidal violence, and positive life experiences

Defendants commonly claim amnesia for their criminal actions especially in cases involving extreme violence. While some claims are malingered or result from physiological factors, other cases may represent genuine partial or complete amnesia resulting from the psychological distress and/or extreme emotion associated with the perpetration of the crime. Fifty Canadian homicide offenders described their memories of their homicide, a non-homicide violent offense, and their most positive adulthood life experience. Self-reported and objective measures of memories for these events revealed that homicides were recalled with the greatest level of detail and sensory information. Although dissociative tendencies were associated with a self-reported memory loss, objective measures of memory quality did not reflect this perceived impairment, suggesting a failure of meta-memory. Recollections of positive life events were superior to those of non-homicidal violence, possibly due to greater impact and meaning attached to such experiences. Findings suggest that memory for homicide typically is enhanced by the powerful emotion associated with its perpetration.

Amnesia for violent crime among young offenders

Amnesia for the perpetration of violent offences is an important issue in medico-legal proceedings. Previous studies of amnesia have mainly relied on selected groups of unconvicted offenders, which raises the question of how reliable the findings are. The purpose of this study was to examine the prevalence and phenomenological qualities of amnesia in violent offenders. In semi-structured interviews with 105 young offenders convicted of serious violence, 20 (19%) reported partial amnesia for their offence and only one (1%) reported complete amnesia. Amnesia was associated with high alcohol intake, emotional ties to the victim, and cognitive processing during the assault. Complete amnesia for violent crime appears to be less frequent than suggested by previous reports using unconvicted samples. The findings have implications for the clinical assessment of claimed amnesia for violent crime and are potentially of medico-legal significance.

Malingering of PTSD: forensic and diagnostic considerations, characteristics of malingerers and clinical presentations

OBJECTIVE

This paper aims to study the detection of individuals malingering posttraumatic stress disorder (PTSD) in criminal and civil situations.

METHOD

A brief history of PTSD and its rise to prominence in legal circles are discussed. The characteristics of individuals who malinger and particularly those who fake PTSD are discussed. Diagnostic dilemmas inherent to the condition, such as the definition of a traumatic exposure, what constitutes a PTSD flashback and the potential for normal symptom exaggeration, are explored.

RESULTS

The typical presentation of malingered symptoms is presented to help clinicians detect commonly seen malingering patterns. Suggestions for interview techniques, Minnesota Multiphasic Personality Inventory test values and sources of collateral information to help detect malingering are reviewed.

CONCLUSION

The paper concludes with a review of the typical presentations of malingered PTSD symptoms and a reminder that physicians need to distinguish legitimate symptoms from faked or embellished presentations.