The Defence of Mental Illness in New South Wales

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Mental illness defence

A New South Wales man who killed his baby girl by throwing her into the Tweed River has been found not guilty of murder by reason of mental illness.

Justice Helen Wilson said in her special verdict in the Supreme Court that the tragedy was a result of the man “labouring under such a defect of reason” he did not know what he was doing was wrong.

‘Cursed baby’

The man pled not guilty to his daughter’s murder, but the special judge-only trial involved the state of the man’s mental health. This occurs when it is accepted that the crime has been committed by the accused person, but a defence of mental health is established.

The baby’s body was discovered by teenagers two days later on a Gold Coast beach having been washed about 20 kilometres north in heavy seas.

The court heard that the man had previously tried to give his ‘cursed’ baby away several times, before ‘sacrificing her life for the sake of the world.’

A long history of schizophrenia

The court also heard that the man, who suffered chronic schizophrenia, had been having hallucinations about killing babies for some 17 years prior to throwing his own daughter into the water.  He had been admitted to hospital on mental health grounds at least 35 times, had not always been compliant about taking medication, and regularly consumed cannabis and alcohol.

His itinerant lifestyle meant that he had no consistent contact with mental health workers, making it virtually impossible for them to adequately treat his mental illness, and although authorities had filed concerns for the safety of his children but the man refused any help.

Testimony from forensic psychiatrist David Greenberg outlined that due to the man’s mental health condition, he truly believed the killing was “justified” to prevent his daughter’s first birthday and the “ending of the world”. 

The defence of mental illness

Justice Wilson concluded all expert evidence supported his mental health condition, and that although this condition was made unquestionably worse by his abuse of alcohol and cannabis, this substance abuse did not discount his “disease of mind” at the time. She determined that he will be detained in a mental health facility until he is deemed fit for release and not a threat to society or himself.

The law in New South Wales

The Mental Health (Forensic Provisions) Act 1990 (NSW) legislates the ‘defence of mental illness’.

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.

In the case of a judge-alone trial, the judge is considered to be the jury for the purposes of the section.

Detention in a mental health facility

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.’

The defence of not guilty by reason of mental illness is not commonly used, but it is an important defence in situations such as this.

There was a similar case in New south Wales last year when a man confessed to police that he had stabbed his son 76 times in the midst of a psychotic episode, believing his son was the devil.

The man’s schizophrenia was well documented by health authorities and known by family and friends.

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Sonia Hickey

Sonia Hickey is a freelance writer, magazine journalist, and owner of 'Woman with Words'. She has a strong interest in social justice and is a member of the Sydney Criminal Lawyers® content team. Sonia is the winner of the Mondaq Thought Leadership Awards, Spring 2022.

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