top of page
Anchor 1


A person who is mentally ill cannot held criminally responsible for their actions. Rather than being dealt with under the criminal justice system, the offender would be dealt with under the Mental Health Act 2007 (NSW) or Mental Health(Forensic Provisions) Act 1990 (NSW).

Part 4 of the Mental Health (Forensic Provisions) Act 1990 (NSW) legislates the criminal defence  of ‘mental illness’.The Part was developed from a line of authorities which have their origins in the case of M’Naghten, known as the M’Naghten Rules.

Section 38 of the Act provides that:

“If, in an indictment or information, an act or omission is charged against a person as an offence and it is given in evidence on the trial of the person for the offence that the person was mentally ill, so as not to be responsible, according to law, for his or her action at the time when the act was done or omission made, then, if it appears to the jury before which the person is tried that the person did the act or made the omission charged, but was mentally ill at the time when the person did or made the same, the jury must return a special verdict that the accused person is not guilty by reason of mental illness.”

If a special verdict of not guilty by reason of mental illness is returned at the trial of a person for an offence, the Court may remand the person in custody until the making of an order under section 39 in respect of the person. Where a jury is involved, section 37 provides that a judge must explain the nature and effect of a special verdict – including the requirement that they will be detained until and unless they are deemed safe to release. In the case of a judge-alone trial, the judge is considered to be the jury for the purposes of the section.

Section 39(1) of the Act states that where such a verdict is returned, “the Court may order that the person be detained in such place and in such manner as the Court thinks fit until released by due process of law or may make such other order (including an order releasing the person from custody, either unconditionally or subject to conditions) as the Court considers appropriate.”

Section 39(2) makes clear that, “[t]he Court is not to make an order under this section for the release of a person from custody unless it is satisfied, on the balance of probabilities, that the safety of the person or any member of the public will not be seriously endangered by the person’s release.”

This means a person in respect of whom a special verdict is returned must be held in a mental health institution indefinitely, until such time the Mental Health Review Tribunal makes a finding that it is safe to release them. For this reason, accused persons may be reluctant to rely on the defence of mental illness and it is encouraged they or their guardian obtain professional legal advice.

If you have been, or know of a person who, has been charged with a criminal offence and suffers from a mental illness of mental condition, it is important that he or she seek legal advice. Should you wish to discuss your options, please contact KF Lawyers.

bottom of page