R v Parks: Defence of Automatism and Public Safety

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3 hours ago

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By: Skylar DeLaronde

Introduction

It is almost unimaginable that a seemingly normal family man would attack and be charged with the murder of his mother-in-law and the attempted murder of his father-in-law. It is even more unimaginable that the accused in such a crime would be found not guilty by relying on the defence of automatism. This is what occurred in the R v Parks decision, where in 1992, the Supreme Court of Canada (SCC) found the respondent, Kenneth Parks, to be not guilty for attacking his parents-in-law despite having driven 23 kilometers in the middle of the night, committing the offences, and driving himself to the police station to confess shortly after. The Supreme Court accepted that Mr. Parks was not guilty of the crimes for which he was accused due to the defence of automatism. Under the defence of automatism, Mr. Parks was sleepwalking when he committed the offences and would be found not guilty. This decision raised many questions about using automatism as a defence, concerns of public safety, and divided the Supreme Court in their reasoning.

Facts

Mr. Parks, the respondent, attacked his in-laws, killing his mother-in-law and seriously injuring his father-in-law.^[i] In the middle of the night, he drove about 23 kilometres from his home to his in-laws’ home and the attack occurred while they were asleep in bed. Immediately following the attack, he drove himself to a nearby police station and told officers what he had done.^[ii] Mr. Parks claimed he was sleepwalking during the incident saying he had “always been a deep sleeper” and often had trouble waking up.^[iii] Mr. Parks was charged with first degree murder of his mother-in-law, and attempted murder of his father-in-law.^[iv] Following the charges, Mr. Parks used the defence of automatism and provided evidence to demonstrate that he was sleepwalking, and was acquitted of the offences at the trial level and the decision was upheld at the Court of Appeal level.^[v] The Supreme Court of Canada saw the main issue as whether sleepwalking should be classified as non-insane automatism resulting in an acquittal or as a “disease of the mind” (insane automatism) which would involve a verdict of not guilty by reason of insanity.^[vi]

Analysis

The Supreme Court was extremely divided in its reasoning in reaching the decision. Eight of the justices weighed in on the decision with varying takes on the reasoning. Ultimately, it was held that the appeal to the SCC should be dismissed.^[vii] The Supreme Court focused much of its analysis on the defence of automatism and what it means in the context of the legal term “disease of the mind.” While Chief Justice Lamer mostly remarked that the trial judge made the right call by instructing the jury to decide on the defence of non-insane automatism,^[viii] La Forest, L’Heureux and Gonthier described that there is a distinction between insane and non-insane automatism to be further drawn out as it relates to somnambulism.^[ix] While the justices focused their analysis on the difference between the insane and non-insane automatism, the average person would still likely have questions as to why or how a person can be found not guilty, and how it was proven that sleepwalking was a sound defence, especially when the accused had driven a long distance and supposedly remained in a sleep state throughout the events. This involves breaking down what automatism means when using it as a defence.

Automatism as a Defence

It is important to understand that in Canadian criminal law there are two legal principles that are looked at when a court determines whether an accused is guilty of a crime for which they are charged: mens rea and actus reus. Mens rea refers to the state of mind an individual was in before committing a crime.^[x] Actus reus refers to the act or omission.^[xi]Both mens rea and actus reus are necessary elements to prove the guilt of an accused, and there are circumstances when the actus reus cannot be proven. The court turned to the analysis used in the Rabey v The Queen decision where Justice Dickson (as he then was) said that automatism “is a basic principle that absence of volition in respect of the act involved is always a defence to a crime…[and] the Crown always bears the burden of proving a voluntary act.”^[xii] There was no dispute that the respondent had committed an act that was involuntary, and the Supreme Court focused on whether sleepwalking should be classified as non-insane automatism or a disease of the mind.^[xiii] What is interesting about the Court’s analysis in determining the nature of the defence is its recognition that a policy component of insanity has emerged in automatism cases. The Court identified two theories: the “continuing danger theory” and the “internal cause theory.”^[xiv]

The continuing danger theory suggests that “any condition likely to present recurring danger should be treated as insanity.”^[xv] The idea that the courts have reached the conclusion that Mr. Parks would not present recurring danger is, at first glance, challenging to digest given that there is no guarantee that the actions of Mr. Parks are incapable of recurring. The court’s conclusion also raises concerns because, although Mr. Parks successfully raised the defence automatism, the Crown would have had to prove that his condition constituted a disease of the mind in order to establish insanity.^[xvi] The disease of the mind, while a legal term, has to examine both a medical and legal component and accordingly, the trial judge should not rely blindly on the medical opinion or aspect of the evidence.^[xvii] However, the trial judge relied significantly on the evidence of medical experts. Some would argue that the policy component of considering the disease of the mind was not fleshed out enough to satisfy the fear instilled in the public. It is, arguably, frightening to the public to know that a person can rely on a defence of automatism in committing an act that involved such a prolonged period of sleepwalking. The court concluded that there is no likelihood of recurrent violent somnambulism and there were no compelling policy factors that show that the “accused’s condition was one of non-insane automatism.”^[xviii] The dissenting justices seemed to consider the public concern in their analysis as they stated that exploring the possibility of some minimally intrusive conditions to assure the community’s safety would not infringe the accused’s section 7 Charter rights, and any conditions must not go further than necessary to protect the public from the danger.^[xix]

Conclusion

Without full understanding why the courts acquitted Mr. Parks of first-degree murder and attempted murder based on automatism, the Parks decision will likely continue to make the public uneasy and perceive the acquittal as a lack of justice served. While automatism has proven to be a sound defence in many instances, it is arguably the length and nature of the respondent’s actions that make this case difficult to process. Further to this point, this case made news headlines when Mr. Parks decided to run for school trustee in his local community in 2006, nearly 20 years after the first-degree murder and attempted murder.^[xx] Although the court followed the legal reasoning for acquitting Mr. Parks based on the automatism defence, but it will likely continue to leave the community with reservations about his actions regardless of whether the crimes were involuntary or not.

Image Description: A bedroom setting with a softly illuminated window and delicate drapes, showcasing a wooden gavel placed on a stack of books on a neatly arranged bed, with framed portraits adorning the walls.

Endnotes:

^[i]^[i] R v Parks, [1992] 2 SCR 871 at p. 871 [Parks], online:< https://canlii.ca/t/1fs9v >.

^[ii] Ibid.

^[iii] Ibid.

^[iv] Ibid.

^[v] Ibid at 872.

^[vi] Ibid at 871.

^[vii] Ibid at 914.

^[viii] Ibid at 896.

^[ix] Ibid.

^[x] Prachi Sanghavi, “The Mens Rea Defence – R. v. Zora” (2020), online (CanLII Connects): <canliiconnects.org/en/commentaries/72952> [perma.cc/XZ3B-U53T]; See also Supreme Court of Canada, “Case in Brief: R. v. Zora” (last modified 23 February 2026), online (Supreme Court of Canda website): <scc-csc.ca/judgments-jugements/cb/2020/38540/> [perma.cc/J8LB-GCUG].