When does the defence of mental health impairment apply?
Mental health impairment and “not criminally responsible” verdicts
In a recent court case, a man set a fire to a stranger’s house and laughed and cheered as the victim inside burned to death. The judge found that he had a mental health impairment and was not criminally responsible for murder.
There was clear evidence Harley Thompson, 28, threw petrol into the Bomaderry house and lit the fire. He yelled abuse, threatening to kill the man if he came out of the burning house. The victim told 000 he was too scared to leave the house and was heard to collapse in the smoke.
Two expert psychiatrists diagnosed Thompson as having schizoaffective disorder or depression with psychotic features. He admitted that he had smoked ice that day and heard voices telling him the victim was a paedophile who had earlier tried to run him over.
Justice Michael Walton, acting as judge alone, found Thompson had a severe psychotic disorder which led to delusions of persecution and hallucinations. The judge said he was satisfied Thompson knew what he was doing, but was not able to reason that his actions were wrong.
“The Court finds the act proven but the accused not criminally responsible for it,” the judge concluded. (Please see R v Thompson (No 1)  NSWSC 1044.)
Thompson was not sentenced or punished by the court, but was ordered to be held as a forensic patient until the Mental Health Review Tribunal was satisfied he was no longer a threat to the public or himself.
Accused individuals with mental health impairment
The decision comes under the relatively new NSW Mental Health and Cognitive Impairment Forensic Provisions Act 2020.
In March 2021 this Act replaced the former law, which could declare a person not guilty by reason of mental illness. (Please see Section 32 Mental Health Act provisions replaced by new legislation in NSW.)
Many victims of crime and their families found these judgements offensive, because they did not say the perpetrator actually committed the crime. Now the perpetrator can be declared to have committed the crime, but not be held criminally responsible. (Please see Community safety at centre of forensic mental health reforms, NSW Health, 28 March 2021.)
Guidance for judges in cases of mental health impairment
The Act also defines mental health impairment and cognitive impairment more clearly and provides guidance for magistrates and judges in cases involving mental health considerations.
Section 4(3) says a person does not have a mental health impairment if the impairment is caused solely by the temporary effect of ingesting a substance, or by a substance use disorder.
This is aimed at ruling out a defence under the Act of acting under the influence of drugs or alcohol. A defence under the Act has to be established as a temporary or ongoing mental disorder, sufficient for clinical diagnostic purposes, that impairs the judgement or behaviour of the person.
It may arise from a mental disorder such as anxiety, clinical depression, bipolar, psychotic or substance-induced mental disorder that is not temporary.
Detainment and treatment when “not criminally responsible”
If there is a finding of not criminally responsible, the accused is nearly always detained in a psychiatric facility and will not be released until the tribunal decides they are no longer a threat to society or themselves.
The tribunal decides what care and treatment they need and where they will be held, be it prison or a high security forensic hospital.
They must face the tribunal every six months and have a lawyer with them representing their interests. They can also have a support person with them.