An experimental investigation of the misinformation effect in crime‐related amnesia claims

Abstract

Summary Research suggests that both internal (i.e., lying) and external (i.e., misinformation) factors can affect memory for a crime. We aimed to explore the effects of post‐event misinformation on crime‐related amnesia claims. We showed participants a mock crime and asked them to either simulate amnesia (simulators) or confess to it (confessors). Next, some participants were provided with misinformation. Finally, all participants were requested to genuinely recollect the crime. Overall, simulators reported less correct information than confessors. Moreover, these two groups were equally vulnerable to misinformation. In addition, exploratory analyses on strategies adopted by simulators revealed that those who previously, mostly omitted information while simulating amnesia exhibited the lowest amount of correct details. Simulators who instead used a mixed strategy disclosed more fabricated memory errors. Findings suggest that legal professionals and jurors should take into account that even offenders, irrespective of confessing or simulating memory loss for a crime, can be susceptible to post‐event misinformation.

Involvement Modulates the Effects of Deception on Memory in Daily Life

“…The more cognitive resources a lying strategy requires, the more impairments it will cause. A number of studies have provided positive evidence for this proposition (Mangiulli et al, 2018(Mangiulli et al, , 2019(Mangiulli et al, , 2020Otgaar et al, 2018b;Battista et al, 2021b). However, the present study suggests that the effects of deception on memory are also modulated when liars with different degrees of involvement adopt the same lying strategy.…”

Creating a false alibi leads to errors of commission and omission

“…In the light of the MAD framework (Otgaar & Baker, 2018), our results suggest that creating a false alibi might be a unique type of deceptive strategy with different mnemonic effects not yet accounted for. However, as seen in studies examining feigning amnesia (e.g., Mangiulli et al, 2020), some participants tend to mix certain deceptive strategies. Specifically, when participants are instructed to feign amnesia, they sometimes not only pretend to have memory loss but also fabricate alternative details which can lead to commission and omission errors (Mangiulli et al, 2020;Mangiulli, van Oorsouw, et al, 2019;van Oorsouw & Merckelbach, 2006).…”

“…However, as seen in studies examining feigning amnesia (e.g., Mangiulli et al, 2020), some participants tend to mix certain deceptive strategies. Specifically, when participants are instructed to feign amnesia, they sometimes not only pretend to have memory loss but also fabricate alternative details which can lead to commission and omission errors (Mangiulli et al, 2020;Mangiulli, van Oorsouw, et al, 2019;van Oorsouw & Merckelbach, 2006). Our results suggest that creating a false alibi might exert similar mnemonic effects as feigning amnesia, and it is possible that this stems from using a combination of deceptive strategies such as fabrication and omitting crucial information.…”

“…We used a 3‐min mock crime video recorded in point of view shot (i.e., video from the angle of what the offender perceives) successfully adopted in previous studies (e.g., Mangiulli et al, 2020; Mangiulli, van Oorsouw, et al, 2019). The video depicts the main character's (i.e., the offender) day, wherein he/she wakes up, goes to work and experiences some hardships (e.g., angry boss), comes home, and makes dinner.…”

Simulating denial increases false memory rates for abuse unrelated information

“…However, in their experiment feigning amnesia did not influence the misinformation effect and Mangiulli et al. (2020) argued that certain limitations related to their design might have been the reason (e.g., the timing of the misinformation and type of memory test used).…”