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

Abstract

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.

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

“…(2022) and Mangiulli, Riesthuis, et al. (2022): I call for a moratorium of further publications on this topic that do not thoroughly assess alternative explanations, including the possibility of feigning, or that inappropriately minimize or discount such concerns. Failure to do impedes scientific progress and invites a reverberation of the Hess debacle that could haunt forensic psychology and psychiatry for decades.…”

“…Various authors have reported that 9%–93% of defendants charged with a serious crime claim amnesia for the crime (Mangiulli, Riesthuis, et al., 2022) with some writers suggesting that these are valid claims (Bourget et al., 2017; Bourget & Whitehurst, 2007; Bradford & Smith, 1979; Harrison et al., 2017; Hopwood & Snell, 1933; Kopelman, 1995, 2002; Parwatikar et al., 1985; Pyszora et al., 2003, 2014). However, many authors have argued or suggested that most amnesia claims, in the context of criminal charges, are likely feigned (Centor, 1982; Cima et al., 2004; Frederick, 2011; Marshall et al., 2005; McNally, 2004; Merckelbach & Christianson, 2007; Ornish, 2001; Otgaar et al., 2019; Peters et al., 2013; Rubenzer, 2018c), including an entire book (Christianson, 2007) directly on point.…”

“…Merckelbach and Christianson (2007) reported that when study participants are asked to play the role of a murderer who is confronted with evidence of guilt in an interrogation, the most frequent strategy is to claim amnesia. and Mangiulli, Riesthuis, et al (2022) reported that published case studies of crime-related amnesia often fail to address explanations other than dissociation:…”

“…(2022) and Mangiulli, Riesthuis, et al. (2022) reported that published case studies of crime‐related amnesia often fail to address explanations other than dissociation:

The evidence offered in support of a dissociative amnesia interpretation was often weak and plagued by an ambiguous heterogeneity with respect to nature, aetiology, and differential diagnoses of alleged memory loss. Most case studies failed to rule out plausible alternative explanations of dissociative amnesia, such as ordinary forgetting and malingering.

They noted that when the possibility of feigning was addressed, it was in a suboptimal way and even when strong evidence was found, such as significantly below chance performance on a forced choice test, it was rationalized or discounted.…”

France lags behind in the application of memory science in the courtroom.

“…Surprisingly, despite the substantial literature on amnesia reported by suspects (e.g., dissociative amnesia, Porter et al, 2001; Taylor & Kopelman, 1984; malingering amnesia, Christianson & Merckelbach, 2004; Mangiulli, Riesthuis, & Otgaar, 2022), the psychologist did not explore this issue. Nor did she address the issue of a probable deficit in encoding abilities, while she mentioned difficulties with short-term memory functions (i.e., “His long-term memory works, but short-term memory is weak”; note that there is no indication in the report that short-term memory and long-term memory were formally tested).…”