A person is not criminally responsible for an offence in New South Wales if the person had a mental health impairment or cognitive impairment at the time of carrying out the act constituting the offence which meant the person:
1. Did not known the nature or quality of their act, or
2. Did not know their act was wrong; in other words, could not reason with a moderate degree of sense and composure about whether their act, as perceived by reasonable people, was wrong.
A person who is found not guilty of a serious offence by reason of mental illness will normally be detained involuntarily at a mental health facility until the conditions for their discharge are met.