Homicidal behaviour among people with avoidant, dependent and obsessive-compulsive (cluster C) personality disorder.

Background Despite a growing forensic psychiatry literature, no previous study has examined in detail homicidal behaviour among offenders with cluster C personality disorders the avoidant, dependent or obsessional personality disorders. Aims This study aims to compare homicide offenders with cluster C personality disorders with those with other personality disorders on criminal history, offendervictim relationship and post-offence reaction variables. Methods The sample was drawn from all Finnish homicide cases of 19962004 for whom a forensic psychiatric evaluation had been conducted. Data were extracted from forensic psychiatric and crime reports. Results In a nationwide sample of 593 homicide offenders, 21 had at least one cluster C personality disorder. These offenders had significantly shorter criminal histories than the others. Offendervictim relationship did not differ between the groups, but confession to the crime and feelings of remorse were more common among people with cluster C disorders. In addition, compared with other personality disorder clusters, co-morbid depression was more common. Conclusions Cluster C personality disorders are rare, but not nonexistent, among homicide offenders. Observed differences in their backgrounds and post-offence behaviours indicate that they may have special needs. Copyright (c) 2012 John Wiley & Sons, Ltd.