Wallace (1986) examined the prevalence of mental disorders among homicide offenders in NSW between 1976 and 1990 and found that in a fourteen year period only 2.8% of offenders in the study were found not guilty by reasons of insanity, although at least 16% of offenders were known to have some kind of mental disorder at the time. ... Mr Wilson had a history of depression for some years and spent 2 weeks in the Rosemount Psychiatric Hospital in 1994, and had been followed up there every 2-3 weeks since notably suffering from abnormal personality disorder with some evidence of brain damage. ... ...