News · Criminal law explainer
Fitness to be tried and the mental health defence.
Some people who come before the higher courts are, because of a mental health or cognitive impairment, unable to take part in their trial, or were not criminally responsible for what they did. The law that deals with this in serious matters is the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW). This note explains fitness to be tried, the special hearing, and the special verdict. It is separate from the section 14 diversion that applies in the Local Court.
By Aaron Kernaghan · Published 3 September 2026
What does fitness to be tried mean?
A person is fit to be tried if they can understand the charge, follow the course of the proceedings, understand the substantial effect of the evidence, instruct their lawyer, and make a defence. The test comes from the case of R v Presser. Fitness is about the person's capacity to take part in the trial, not about guilt.
Fitness can be raised by the defence, the prosecution, or the court. If it is raised, the question is decided by the court on the balance of probabilities. A person can be unfit even though they knew what they were doing at the time of the offence; the two questions are different.
What happens if a person is found unfit?
If a person is found unfit, the ordinary trial cannot proceed. The court considers whether the person is likely to become fit within a set period. If they are not, the matter goes to a special hearing.
The person's condition and prospects are assessed with expert evidence. The aim is to deal with the person fairly, neither trying someone who cannot take part, nor simply setting the allegation aside.
The special hearing
A special hearing is conducted as much like a trial as the person's condition allows. It decides whether, on the evidence, the accused committed the act that constitutes the offence. The outcomes are limited: not guilty, a special verdict of act proven but not criminally responsible, or a finding that on the limited evidence available the accused committed the offence.
Where the last finding is made, the court can impose a limiting term, which is the sentence the person would have received had they been convicted at an ordinary trial. The person is then dealt with under the forensic system rather than in the ordinary way.
The mental health defence and the special verdict
Separate from fitness is the defence that a person was not criminally responsible because of a mental health impairment or cognitive impairment at the time of the offence. Where that is established, the outcome is the special verdict of act proven but not criminally responsible, which replaced the older verdict of not guilty by reason of mental illness.
The special verdict is not an acquittal in the ordinary sense. The person is not punished, but they can be made subject to orders, including detention or supervision, managed by the Mental Health Review Tribunal, with release depending on risk.
Why expert evidence and early advice matter
These matters turn on careful expert evidence about the person's capacity and condition. Reports from psychiatrists and psychologists are central, and the way the issue is raised and run can change the outcome entirely.
For a person with a serious mental health or cognitive impairment facing serious charges, this is specialised work. Advice early, so the right assessments are obtained and the right course is chosen, makes a real difference. Our note on the Local Court diversion covers the different pathway for less serious matters.
Frequently asked.
What does fit to be tried mean?
A person is fit to be tried if they can understand the charge, follow the proceedings, understand the effect of the evidence, instruct their lawyer, and make a defence. The test comes from R v Presser. It is about capacity to take part, not guilt.
What happens if someone is found unfit to be tried?
The ordinary trial cannot proceed. If the person is not likely to become fit within a set period, the matter goes to a special hearing that decides, as far as possible, whether the accused committed the act constituting the offence.
What is a special hearing?
A hearing conducted as much like a trial as the person's condition allows, to decide whether the accused committed the act that constitutes the offence. It can result in a not guilty finding, a special verdict, or a finding that the accused committed the offence, which can attract a limiting term.
What is the special verdict?
A verdict of act proven but not criminally responsible, made where the person was not criminally responsible because of a mental health or cognitive impairment at the time. It replaced the older verdict of not guilty by reason of mental illness.
Is the special verdict an acquittal?
Not in the ordinary sense. The person is not punished, but they can be subject to detention or supervision managed by the Mental Health Review Tribunal, with release depending on risk.
To speak to a criminal defence lawyer, call Aaron Kernaghan on 0421 717 019.
This article is written by Aaron Kernaghan, criminal defence lawyer at Good Legal Lawyers, as at 3 September 2026. It is commentary and reflects the personal opinion of the author only. It is not legal advice, it is not a substitute for advice on your own matter, and it does not purport to be accurate or complete. Any matter referred to may be before the court and any person charged is presumed innocent. For advice on a specific matter, contact Aaron Kernaghan on 0421 717 019 or contact the firm.
More criminal-law commentary by Aaron Kernaghan.