Mental Disorder and Dangerousness

Abstract

Psychiatrists are called upon to make judgements on the future dangerousness of mentally disordered subjects in civil commitment procedures, in the criminal courts, and during the decision process on the release of offenders on indeterminate sentences or committals. The ability of psychiatrists to make these judgements is increasingly under challenge. The difficulties of making useful predictions when the base rate for the event to be predicted is low, is now well recognised. Less obvious are the problems attendant upon making socially useful predictions on psychiatric grounds in populations with a high base rate for future offending. The evidence pertaining to the level of violence amongst the mentally disordered is reviewed. The lesson to be drawn from the empirical evidence is that mental abnormality of and in itself contributes little to the prediction of the predisposition to act violently. The question remains as to whether there are definable groups or classes within the generality of mentally abnormal individuals for whom there is an increased risk of future violence. It would be compatible with both the research studies and common clinical impression if the mentally abnormal contained subgroups with unusually violent predispositions balanced by larger groups with less than average propensities to aggression. The literature is largely inadequate to delineate such high risk groups with the degree of certainty ideally needed to instruct clinical decisions, but does suggest that such groups exist and are capable of further empirical definition.

Facing Up to Unpalatable Evidence for the Sake of Our Patients

“…Equally it was essential to overcome similar, though more politely articulated prejudices among those who controlled public mental health services, including most of our older colleagues. The question of an association was in those days as much a political as a scientific question, and it was in the guise of scientists that we answered politically [2]–[4]. The efforts to minimise, or if possible explain away, the apparent association between schizophrenia and violence was remarkably effective, and up to a point beneficial to patients.…”

Debate: Clinical risk categorization is valuable in the prevention of suicide and severe violence? Yes

“…6,7 These arguments are not new. 2 We contend they are the wrong arguments. Clinical risk management is not about prediction but prevention.…”

“…Mullen: 2 Critics of false positive rates in the prediction of dangerousness assume that dangerousness is not a probability but a quality only waiting the right moment to manifest.…”

Verbal Intelligence and Criminal Offending Among Men With Schizophrenia

“…Some decades ago, a controversial question was whether people with schizophrenia were more prone than others to commit criminal offences or not. The debate clearly had political grounds and was primarily focused on the right to keep mentally ill individuals institutionalised because of their presumed "dangerousness" (Mullen, 1984;Shah, 1975). Research was still underdeveloped and there was no robust empirical evidence in support for the commonly held view that individuals with schizophrenia did not commit more crimes than did non-disordered individuals.…”