Among all criminal defence strategies, few are as widely misunderstood as the insanity defence. Popular culture — particularly television courtroom dramas and high-profile criminal cases — often portrays insanity as a loophole that allows accused persons to escape criminal responsibility entirely. In reality, the insanity defence in Canada is narrow, highly technical, rarely successful, and often carries serious long-term consequences.
Public attention to the defence increased significantly following the 2021 trial of Alek Minassian, who faced multiple counts of first-degree murder and attempted murder for the 2018 Toronto van attack. Minassian argued that he was not criminally responsible due to a mental disorder linked to autism-spectrum thinking. The court rejected this argument and found him criminally responsible on all counts, reinforcing the strict legal threshold required to succeed with this defence.
Statistics Canada data consistently show that fewer than 1% of accused persons raise a mental disorder defence, and only a fraction of those cases result in a finding of Not Criminally Responsible on Account of Mental Disorder (NCRMD). Despite its rarity, the defence remains a critical legal mechanism in cases involving serious and genuine mental illness.
This article provides a comprehensive, up-to-date explanation of the insanity defence in Canadian criminal law, grounded in section 16 of the Criminal Code, Part XX.1 (Mental Disorder), and relevant jurisprudence. It explains how the defence works, how it differs from unfitness to stand trial, what happens after an NCRMD finding, and why invoking the defence can carry consequences as severe as, or even more severe than, a criminal conviction.
The concept of exempting individuals from criminal punishment due to mental incapacity is not modern. Legal systems, as early as Babylonian law (circa 1700 BCE), recognized that culpability required mental capacity. Roman law later adopted the concept of non compos mentis , requiring a “sound mind” for criminal responsibility.
Modern Canadian insanity law traces its roots to the M’Naghten Rules, developed in England in the 1840s. These rules established that an accused could be exempt from criminal responsibility if, due to a “defect of reason from disease of the mind,” they either:
This framework heavily influenced Canadian criminal law and remains embedded — albeit in modernized form — within today’s Criminal Code .
Canada first codified the insanity defence in the 1892 Criminal Code . Early versions of the law were punitive: individuals found insane or unfit were often detained indefinitely “at the pleasure of” provincial authorities, frequently for life.
Substantial reforms occurred in the late 20th century, culminating in the modern structure found in Part XX.1 of the Criminal Code, which emphasizes public safety, proportionality, and treatment rather than punishment.
The insanity defence is codified in section 16 of the Criminal Code of Canada:
This provision establishes three critical legal principles:
The Criminal Code defines a mental disorder as a “disease of the mind.” Courts have interpreted this narrowly. Temporary emotional states, intoxication, personality traits, or moral failings do not qualify.
Examples of conditions that may qualify include:
Conditions such as autism, ADHD, or personality disorders, on their own, generally do not meet the legal threshold unless accompanied by a qualifying psychotic impairment.
Although often confused, NCRMD and unfitness to stand trial are legally distinct concepts.
Section 2 of the Criminal Code defines “unfit to stand trial” as the inability, due to a mental disorder, to:
When fitness is in question, courts may order psychiatric assessments and conduct a fitness hearing.
If found unfit, the accused may be:
Individuals found NCRMD or unfit fall under Part XX.1 – Mental Disorder of the Criminal Code . Their cases are transferred to a provincial Review Board, whose mandate is to determine whether the accused poses a significant threat to public safety.
The Review Board must impose the least onerous and least restrictive disposition consistent with public safety.
Possible dispositions include:
Cases are reviewed annually (or every two years in limited circumstances).
“A finding of NCRMD transfers control from the criminal courts to a mental health tribunal, often for years.”
— Heather Spence, Criminal Defence Lawyer & Partner
NCRMD is an affirmative defence, meaning it must be proven by the party raising it — usually the defence, though sometimes the Crown.
The accused must establish:
This typically requires:
The Crown often counters with its own experts and circumstantial evidence suggesting awareness or planning.
Even when successful, the insanity defence is not a path to freedom.
Key limitations include:
In some cases, individuals found NCRMD remain under state control longer than they would have been incarcerated if convicted.
“The insanity defence is not an escape hatch — it is a transfer into a different, and often longer, legal regime,”
— Robbie Tsang, Criminal Defence Lawyer & Managing Partner
Experienced criminal defence lawyers approach NCRMD cautiously. It is typically considered only when:
In many cases, counsel may instead pursue:
The Greater Toronto criminal defence lawyers at Mass Tsang approach mental disorder defences with precision and caution. While NCRMD is rarely invoked, it is fully considered when mental illness plays a genuine and significant role in an alleged offence.
Every case is assessed individually, balancing legal strategy, medical evidence, and the client's long-term consequences.
If you or a loved one is facing criminal charges involving mental health issues, early and informed legal guidance is essential.
Contact Mass Tsang today for a confidential consultation.
In Canada, the insanity defence is legally referred to as “Not Criminally Responsible on Account of Mental Disorder” (NCRMD). It applies when an accused, due to a mental disorder at the time of the offence, was incapable of appreciating the nature and quality of their actions or knowing they were wrong.
NCRMD means the accused committed the act but is not criminally responsible because of a qualifying mental disorder. It is not an acquittal and does not automatically result in release.
The party raising the defence — usually the accused — must prove, on a balance of probabilities, that a mental disorder existed and met the legal test at the time of the offence.
No. Unfitness to stand trial concerns the accused’s ability to understand court proceedings and communicate with counsel. NCRMD focuses on the accused’s mental state at the time the offence was committed.
The case is transferred to a provincial Review Board, which determines whether the individual should receive an absolute discharge, conditional discharge, or be detained in a psychiatric hospital, based on public safety considerations.
Not necessarily. Individuals found NCRMD may remain under Review Board supervision for many years and, in some cases, longer than they would have served in prison if convicted.
