Mental illness, violence and delusional misidentifications: The role of Capgras' syndrome in matricide

Background Violent behavior has frequently been reported in cases of Capgras' delusion, a misidentification syndrome characterized by the false belief that imposters have replaced people familiar to the individual. Aims To better understand the relationship between Capgras' syndrome and violence. Method After a brief overview of the scientific knowledge of delusional misidentification syndromes, we present two cases of psychotic sons suffering from this kind of delusion who killed their mothers and we analyzed the phenomenology of Capgras' delusion in-depth, focusing on the role of this syndrome in the etiology of violence. Results Capgras' syndrome may be a specific risk factor for violence towards others, particularly the murder of the delusionally misidentified person. Conclusions Looking for the signs of Capgras' syndrome may be crucial to assessing the risk of violence in mentally disordered patients