A 21-year-old Coffs Harbour man was recently found not guilty of breaking into a nearby home while naked and assaulting a woman in her bedroom – because he was deemed to be sleepwalking.

The defence successfully argued that he was suffering from a state of "automatism, namely somnambulism" – sleepwalking in plain language.

The defence argued that the accused therefore did not have the "requisite mens rea" to commit the offence. The legal term "mens rea" means a person has to have the awareness or knowledge that they are committing wrong in order to be convicted of a crime.

Accused claims to have no knowledge of his actions

In this NSW case, R v Jacob Bradley Holland [2017] NSWDC 47, police officers said the man slurred his words, appeared drunk and smelt of alcohol. He said he had drunk six cans of beer and gone to bed. He claimed the next thing he knew he was being held down in a strange house.

The judge said there was no dispute that the accused had entered the house illegally and assaulted the woman in her bedroom. The woman's partner subdued the accused until police arrived. Police said at the time of his arrest he was mumbling and yelling incomprehensibly.

The accused told police that in retrospect he thought he was in a dream where he was acting out a character from the roleplaying computer game "Skyrim".

History of bizarre behaviour while sleepwalking

The defence medical expert said the accused had been a sleepwalker from an early age and his symptoms in the case were consistent with sleepwalking. His violent acts were said to be caused by "sleep drunkenness", a condition whereby behaviour during sleepwalking can be aggressive.

The defence said he was diagnosed with ADHD when he was four and it was then he started sleepwalking. He had been on Ritalin for many years and was diagnosed with Asperger's syndrome when he was fourteen. His brother told the court the accused had long done "weird and crazy" things when he was asleep, including once waking their mother to say: "I was inside a sandwich bag in the wardrobe".

Aspects of behaviour inconsistent with somnambulism

The Crown's medical expert said that the accused managed to enter the home silently and at one stage turned his head to make eye contact with the victim before the assault. This, the expert said, indicated that the accused's conduct was goal directed, not that of a sleepwalker.

The Crown's expert told the court that the accused had managed to travel a complicated path undetected to the woman's bedroom door, which was inconsistent with automatism.

Prosecution fails to prove that accused was not sleepwalking

The case was heard by a judge alone who found there was no motive. The accused had never seen the woman before, or been in the house.

The judge found that the prosecution had not satisfied him beyond reasonable doubt that the accused was not sleepwalking at the time. Therefore his conduct was not voluntary.

"Unless the Crown proves beyond reasonable doubt that the act of the accused was subject to the control and direction of his will, then he must be acquitted because no offence has been committed," Judge Phillip Mahoney said in his judgment.

An important legal factor for the judge was the 1990 High Court decision in R v Falconer [1990] HCA 49 concerning the proper construction of sections 23 and 27 of the Criminal Code (WA), which refer to a defence of automatism for criminal acts.

Sleepwalking law has history of violent acts

This is not the first time a person has been found not guilty of a crime due to sleepwalking.

In 1950 a Melbourne mother axed her daughter to death believing she was fighting off enemy soldiers. She was acquitted as she was found to be sleepwalking.

In 1987 in Canada, Kenneth Parks drove 23 kilometres to his mother-in-law's house, stabbed her to death and strangled his father-in-law almost to death. He got back in his car, drove to a police station and told them he'd found blood on his hands and feared he'd just killed someone, insisting he had no memory of the event.

He was charged with murder. (See R. v Parks, [1992] 2 S.C.R. 871.) He had good relations with his in-laws, but his whole family had a history of sleepwalking. Experts said he had been sleepwalking during the murder, and he was acquitted.

But don't think sleepwalking is a ready defence. In all of these cases there was a long history of sleepwalking. Plenty of sleepwalking claims have been thrown out of court, and the question of "mens rea" remains a vexed area of law.

Nathan Luke
Criminal law
Stacks Law Firm

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