This defence can be raised on the balance of probability that at the time of the offending, you:

  • Acted under a ‘defect of reason’ due to a ‘disease of the mind’ and because of the mental illness, you did not understand that what you were doing was wrong in accordance to the standards of a reasonable person.

Mental illness can be ongoing or temporary, curable, or incurable. However, you are unable to raise this defence in situations where you acted under the influence of alcohol or drugs.

If you are successful in this defence, the court will find you ‘not guilty by reasons of mental illness’ and you will be detained in a mental institution until you are assessed as fit to be released in the community.

If your mental illness is shown as incurable, then you may be detained in the institute for an indefinite period of time.