Dangerousness in the delusional misidentification syndromes is studied by reviewing a sample of 82 cases defined by either verbal threats or physical violence caused by a misidentification delusion. Eighty cases were obtained from a review of the anglophone psychiatric literature in which the patients exhibited some degree of dangerousness, to which we added 2 previously unreported cases.

Individuals suffering from misidentification syndromes may present with right hemispheric pathology and deficits in facial recognition. In addition, misidentification delusions have been associated with aggressive behaviour. The possible linkage between misidentification phenomena, facial recognition, and aggression is discussed, illustrated by the case of a patient suffering from an organic delusional disorder.

Delusions involving the antichrist concept have been occasionally reported. Some cases of the antichrist delusion have been associated with violent behavior. In this article we describe the case of a man who suffered from a chronic antichrist delusion and who also displayed repeated and serious violent behaviors. We also discuss the role of the antichrist delusion as well as other psychotic symptoms in the genesis of violence in the present case.

A series of 20 patients suffering from delusions of physical and psychological transformation of the self is studied. Nosological, psychosocial, and biological aspects are discussed. Two cases are presented in detail.

The job of the security guard is generally regarded as stressful because of the potential for violent or other hostile confrontation. Although the public assumes that only mentally healthy individuals who possess the capability to handle stressful situations become employed as security guards, this may not be the case. A series of 15 individuals who suffered from psychotic disorders while working as security guards is studied and discussed in terms of the issues of dangerousness and public safety. One case is described in detail in order to highlight important issues resulting from being psychotic while working as a security guard.