The delusional misidentification syndromes (syndromes of Frégoli, Intermetamorphosis, Subjective Doubles and Capgras) are characterized by delusions of misidentification of other persons or of one-self. Aggressive ideas or behaviours often go with these delusions, but the problem received relatively little attention. Capgras’ Syndrome is characterized by the delusional belief that a well-known person has been replaced by a double. The delusion frequently involves significant others and takes place in a paranoid atmosphere with feelings of strangeness and unreality. We stress the importance of considering the potential dangerousness and homicidal acts directed towards family members of patients with Capgras’ Syndrome.

We report a case with histories of paranoid schizophrenia and alcohol and cannabis intoxications who developed a Capgras’ Syndrome associated with homicidal behaviours toward his wife.

Our case met DSM IV-TR diagnostic criteria for paranoid schizophrenia, according to previous studies which show that paranoid schizophrenia is the most frequent mental disorder associated with delusional misidentification. The psychopathological analysis show that homicidal acts are connected to anguish of the ego disintegration and failure of defense mechanisms.

According to the most recent literature, our findings suggest that Capgras’ Syndrome may be linked to a genesis of aggressive behaviours; alcohol and substance intoxications facilitates impulsivity and dissociation. The patients’ acting out directed toward family members occurs during a psychotic breakdown. Capgras’ Syndrome should always be evaluated in order to prevent violent acts.