Can Sleepwalking Be a Legal Defence for Murder?
(Read Time: 3 Minutes)
By Ollie Coull
Imagine waking up in the middle of the night, standing in a room you do not recognise, covered in blood. You look down, and someone is dead on the floor. You have absolutely no memory of how you got there, what happened, or why you did it. You were completely asleep the entire time. When the police arrest you for murder, can your lawyer seriously look a judge in the eye and say, "It wasn't my client, it was their sleepwalking"? It sounds like the ultimate lazy excuse or a wild plot twist from a courtroom drama, but in both US and UK law, sleepwalking is a completely real, valid legal defence. It has actually worked in some of the most high-profile murder trials in history. But the way the courts handle a sleeping killer is incredibly complicated, totally weird, and can lead to two completely opposite results depending on which side of the ocean you are on.
To understand how you can defend yourself by saying you were asleep, you have to look at the absolute foundation of criminal law. To convict someone of a serious crime like murder, the prosecution has to prove two things: the physical act of the crime, and a guilty mind. If you are deeply asleep, your brain is essentially switched off from reality. You aren't making conscious choices, which means your mind cannot be guilty. In the legal world, this falls under a concept called automatism, meaning your body was basically operating like an unthinking robot. The real legal chaos starts when courts try to decide what kind of automatism sleepwalking actually is. This is where the US and the UK completely split.
In the US, courts generally treat sleepwalking as non-insane automatism. If a jury actually believes you were asleep when you committed the violence, you get a clean acquittal. You are found not guilty, you walk out of the front doors of the courthouse, and you go straight home to your own bed. This happened in a famous Canadian case that US courts heavily look to, where a man named Kenneth Parks fell asleep on his sofa, woke up, drove twenty-three kilometres to his in-laws' house, attacked them with a tyre iron, and killed his mother-in-law. Experts proved his brain was in a deep stage of sleep the entire time and that he had a massive family history of sleep disorders. He was acquitted of everything and walked away a free man.
But over in the United Kingdom, the House of Lords and the Court of Appeal came up with a much more terrifying rule. Under ancient English legal guidelines called the M'Naghten Rules, any condition that messes with your internal reasoning faculties is legally defined as a disease of the mind. In a landmark UK case called R v Burgess, a man attacked his friend with a video recorder and choked her while sleepwalking. The court looked at the medical evidence and ruled that because sleepwalking is caused by an internal abnormality within the brain's sleep cycles, it counts as a temporary disease of the mind. Because of that ruling, if you successfully use a sleepwalking defence in the UK, you do not get a normal acquittal. You get a special verdict of not guilty by reason of insanity. Even though you are technically not guilty of the murder, the judge can immediately order you to be detained in a high-security psychiatric hospital indefinitely to protect the public. For obvious reasons, this makes the defence incredibly dangerous for UK lawyers to use, because trying to prove you were asleep could land you in an asylum for the rest of your life.
Getting a jury to believe you were sleepwalking is also one of the hardest things a defence team can ever try to do. The prosecution will rip your life apart looking for a motive, because real sleepwalking violence is almost always completely random and senseless. If the police find out you hated the victim, owed them money, or were having an argument right before bed, your sleepwalking defence is immediately dead in the water. They will also look at your behavior right after the crime. In another famous case in Arizona, a man named Scott Falater stabbed his wife forty-four times, hid the knife in his car, put his bloody clothes in a laundry basket, and washed his hands. He claimed he was sleepwalking, but the jury found him guilty of first-degree murder and sentenced him to life in prison. The court ruled that his actions were far too complex, coordinated, and calculated for a sleeping brain to execute.
At the end of the day, criminal law recognizes that it is morally wrong to punish someone for an action their conscious mind had absolutely no control over. If the science backs you up, your history checks out, and you have no reason to hurt anyone, the law accepts that a sleeping body can be a lethal, blameless weapon. But courts are incredibly careful with this defence. The rules are designed to protect truly innocent people suffering from severe medical conditions, while making sure that anyone trying to use sleepwalking as a fake excuse to get away with murder will face a life sentence or indefinite confinement.
References (APA 7)
Arizona v. Falater, 197 Ariz. 202 (2000).
Bratty v. Attorney-General for Northern Ireland, AC 386 (1963).
M'Naghten's Case, 10 Cl & F 200 (1843).
R v. Burgess, 2 QB 92 (1991).
R v. Lowe, EWCA Crim 224 (2005).
R. v. Parks, 2 S.C.R. 871 (1992).
