Dissociative identity disorder in forensic field: Case report and literature review

Dissociative identity disorder is characterized by the disintegration of identity into two or more distinct personality states and the inability to recall everyday events, important personal information, and/or traumatic events. The distinctive elements, which constitute the core symptoms of the disorder, are identity confusion, identity alteration, and amnesia. We present the case of a 47­year­old man who contacted a hitman to kill his wife's mother­in­law. After being arrested, the man claimed to know nothing about the affair and to be possessed by his father­in­law, who had died a few years earlier in a car accident. According to the defendant's narration, the father­in­law possessed the man and planned the death of his daughter and wife in revenge. A forensic psychopathological evaluation was performed to determine whether the man was suffering from DID or whether he was simulating possession. the assessment of these cases remains a very complex challenge from a medico­legal point of view and for court decisions. The assessment of the patient should be carried out by several independent psychiatrists by means of multiple tests (i.e. Dissociative Experiences Scale, Dissociative Disorders Interview Schedule, self­assessment questionnaires, analysis of verbal and non­verbal behaviour) and a multidisciplinary approach. In this way, an evidence­based approach can be developed to answer the fundamental question: how to distinguish real pathology from a simulation?.