Autism plus psychosis: a 'one-two punch' risk for tragic violence?

In the recent series of mass murders in Connecticut, Colorado, Norway and elsewhere, a pattern appears to emerge: young men whose social isolation borders on autism apparently become prey to psychotic ideation, and under its influence commit horrific violence. We argue that in some of these tragic cases two concomitant diagnoses may be at play, namely autism and psychosis. Autism itself is not an intrinsically violent disorder, and individuals with autism spectrum disorder (ASD) are no more prone to violent behaviors than the general population. The additional presence of psychotic illness, however, may dramatically change the picture. Based on an examination of historical and contemporary data regarding psychosis and violence in patients without developmental disability we explore three points relevant to the possibility of violence in individuals with comorbid ASD and psychosis. (1) Individuals with ASD have an elevated risk of comorbid psychopathology, including psychosis, which is strongly associated with violence. (2) The content of psychotic ideation has become increasingly violent and lethal in recent decades. (3) It is possible that individuals with ASD are readier than others to act on psychotic impulses. We conclude that there may be a kind of one-two 'vulnerability punch,' giving individuals with ASD a baseline higher risk of comorbid psychiatric illness, not infrequently including psychosis. Recognizing the increased susceptibility of individuals with autism other neurodevelopmental disability to concomitant psychotic illness increases the possibility that they can be correctly identified and treated, mitigating tragic outcomes.