Psychiatric symptoms associated with the mental health defence for serious violent offences in Queensland.

OBJECTIVE: The purpose of this study was to examine which psychiatric symptoms were associated with a defence of unsoundness of mind for serious violent offences.

METHOD: The study included psychiatric reports provided by forensic psychiatrists from the High Secure Inpatient Service for patients found to have a mental health defence by the Mental Health Court between June 2004 and June 2009.

RESULTS: The defence of unsoundness of mind was invariably associated with psychotic symptoms. All reports concluded that the patient was deprived of knowledge of the wrongfulness of the act. Patients found to be additionally deprived of the capacity to understand their actions suffered delusional beliefs about the identity of the victim. The symptoms that resulted in a small number of patients being considered deprived of the capacity to control their actions were mixed, but approximately a third suffered passivity phenomena.

CONCLUSIONS: Psychiatrists should be specific about how the patient's symptoms link to any deprivation of capacity. Report writers could comment upon the presence or absence of Axis II conditions and the likely impact of any substances in the patient's system at the time of the offence.