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. Detecting malingering in such cases is substantial part of forensic psychological and psychiatric assessment.

To identify possible psychological differences among homicide or severe violence offenders presenting amnesia for the event and those who do not.

We examined homicide or severe violence offenders presenting amnesia for the event (n=15) and those who do not (n=15). Methods for assessment of cognitive functions (WAIS-III, WMS), dissociation (DES-20, MID), impact of events scale (IES), and personality (ROR, MMP-II) were used. Further we evaluated social and criminal anamnesis. Offenders with psychotic or schizophrenic symptoms were excluded.

No differences in cognition or personality was found (p < 0.01). Elevated levels of dissociation and score in IES questionnaire was found in offenders presenting amnesia for the event.

This pilot study supports hypothesis that there are no any neuropsychological impairments in nonpsychiatric offenders of murder or severe violence presenting amnesia. Higher level of dissociation and score of impact of events scale (p < 0.05) suggest, that this group of offenders may be more predisposed to dissociative and stressful reactions in overloading events. Thus the question whether the amnesia is malingered or not is still unclear.