Mentally disordered attackers and killers: Towards a taxonomy

Abstract

Only a very small percentage of papers on homicide deal with multiple killers in spite of their intrinsic and theoretical interest for forensic clinicians. It is argued that prediction of future violent behaviour is one of the most important aspects of forensic psychiatry and psychology, particularly for mental health review tribunals (MHRTs) and for administrative officials. This article presents an analysis of interpersonal violence in terms of three broad interrelated concepts: ‘internal’ motivation, self-control and environment. Factors which predispose individuals to interact violently with their environment raise the probability of the occurrence of a particular piece of behaviour so that a range of precipitating factors will produce the behaviour. In other contrasting instances the precipitating or ‘trigger’ factors are pre-eminent in the understanding of the genesis of the behaviour. Attacks are dichotomized as premeditated and unpremeditated, and these two contrasting styles are described in terms of attack characteristics, weapons and psychiatric formulation. The utility of this taxonomy is discussed for crime investigators, clinicians and those officials who have to make decisions about detention in and release from secure accommodation.

Key Words:

• classification
• killers
• taxonomy
• violence