By Jean Balchin 10/01/2018

Parts One and Two can be read here…

On a warm summer evening in July 2008, retiree Brian Thomas and his wife Christine sat their campervan, watching the sun sink into the sea. The couple spent their retirement watching rugby together and traveling the countryside. After heading to bed, Brian and Christine were awoken at 11:30 by a bunch of rowdy teenagers. Unable to sleep, they drove to another location and fell asleep again. The next thing Brian knew, he was awake, with his hands tightly grasping Christine’s neck as she lay unresponsive. Panicking, he called 999,

“I think I’ve killed my wife!” he told the operator. “Oh, my God. I thought someone had broken in. I was fighting with those boys, but it was Christine. I must have been dreaming. What have I done?”

Was Brian Thomas to blame for the death of his wife, or was the event merely a tragic accident over which he had no control? He was eventually cleared of murder after the Crown Prosecution Service accepted he had not been in control of his actions but was not a danger to anyone else.

Ken Parks

Brian Thomas was hardly the first person to employ the sleepwalking defence. In 1987, a 23-year-old Canadian man named Kenneth Park picked himself off the couch one night after falling asleep watching Saturday Night Live, drove 14 miles on a busy highway, let himself into his in-laws’ house and stabbed his mother-in-law to death with a carving knife. He then throttled his father-in-law and drove to a nearby police station. Without paying heed to his bloody, shredded hands, he walked in and said, “I’ve just killed two people. My God, I’ve just killed two people.” He then looked down, and as if registering his blood-soaked hands for the first time, screamed, “My hands!” Lady Macbeth would be proud. Aside from recent money troubles, Parks was not stressed, and he had no motive for killing his in-laws. He couldn’t remember any part of the bloody episode, and in one unnerving moment, he asked how his in-laws were. A detective told him that his mother-in-law was dead, to which Parks replied “Did I have anything to do with it?” The officer couldn’t decide whether Parks was delusional or the best actor he’d ever met.

Parks’ attorney wanted him to plead insane, arguing that a sleepwalker has no way of recognising right or wrong. Parks refused to do so, fearing that his possible institutionalization might prevent him from seeing his daughter. Therefore, his lawyer argued that he couldn’t be responsible for something he never chose to do, and couldn’t be deemed insane for the temporary state of sleepwalking. Parks’ case was taken up by Rosalind Cartwright, one of the world’s preeminent sleep researchers.

Cartwright conducted a number of several sleep studies and thoroughly investigated Parks’ family sleep history, concluding that he was in the midst of a complex parasomnia from the time he got up off of the couch to the time he walked into the police station.

“He was a gentle man stuck in a tragic circumstance,” she says.

Parks had an extensive family history of parasomnia; his grandfather cooked while sleepwalking and a number of his male relatives wet the bed throughout adulthood. Moreover, Parks’ violent outburst was consistent with the actions of other sleepwalkers when confronted. On the odd occasion my parents have risked waking me up, I’ve screamed blue murder. I once threw a lamp at my poor mother. Anyway, the defence argued that Parks responded violently to his mother-in-law confronting him when he entered the house, which would explain why he killed a loved one without any clear intent. Parks was acquitted on all charges. Soon a trend of sleepwalking defences developed; psychologists and prosecutors became concerned about the prospect of malingering.

The Question of Responsibility

Given that there is no set framework for assessing whether a defendant was sleepwalking when violence occurred, a person’s fate often depends on the sophistication of the attorney and the sleep experts who testify. The notion of responsibility in cases of sleepwalking violence is a hugely controversial issue, and many judges and lawyers remain unconvinced that someone could execute a complex and violent act while sleeping. The question of whether a person was sleepwalking or not could mean the difference between a full acquittal or prison—with the possibility of the death penalty. There is no middle ground between incarceration and freedom, and no record of how often police deal with cases of possible sleepwalking. Obviously, the way courts view sleep needs to change, especially considering that the foundations of the criminal code relating to involuntary states such as sleepwalking haven’t been updated since the 1950s.


Moving on from murder to something a little less deadly, but just as indecent: sleep sex, or sexsomnia. This is a condition wherein a person will engage in sexual activities while asleep. In extreme cases, sex sleep has been alleged, and accepted, as at least a part of the cause of sexual assault, including rape. Sexsomnia, like regular sleepwalking, is considered a type of non-rapid eye movement sleep (NREM) parasomnia, and may occur alongside other sleep disorders such as sleepwalking, sleep apnoea, night terrors and bedwetting and can be triggered by stress, previous sleep deprivation and excessive consumption of alcohol or other drugs. In a 2007 article published in Sleep, researchers Carlos Schenck, Isabelle Arnulf and Mark Mahowald catalogued a wide range of sleep related sexual behaviours that includes masturbation, fondling, sexual intercourse with climax, and sexual assault/rape, which usually had unpleasant consequences, although there are some reports of pleasurable effects.

Sexsomnia is intriguing. Photo by Kalegin Michail on Unsplash.

While researching this, I stumbled upon a case of an Australian woman having sex with strangers while sleepwalking. For several months, this poor woman would go walkabout in the middle of the night, engaging in intercourse with the odd stranger, while her hapless boyfriend lay snoring in bed. The woman and said boyfriend were only alerted to her behaviour when her partner awoke one night to find her missing, and went out searching for her, only to find her engaged in the sex act. Peter Buchanan, the sleep physician at Sydney’s Woolcock Institute of Medical Research aptly described the situation: “Incredulity is the leading player in cases like this.”

So why does sexsomnia happen? Well, the subcortal area of the brain regulates basic biological impulses such as breathing, eating, aggression and arousal. The cortex (the largest part of the brain) usually polices these primal instincts while we’re awake, however during sleeping, the cortex doesn’t operate fully – but the primal instincts still continue to fire off. Normally, this activity doesn’t disturb a sleeping person, but if the person is incredibly tired or has been drinking, or has a sexual dream, sexsomnia can occur. “From what we understand, sleep sex occurs before the muscles are paralyzed by REM,” says Professor Mangan, a leading sleep researcher. Since the brain is never fully shut off, it makes sense that people can do complex things in their sleep, especially activities like sex that involve muscle memory,” he says.

“There have been cases of people driving, moving heavy objects, or cooking — why should having sex be any stranger?” 


The mind is a strange and wonderful organ. Sleepwalking is merely the tip of the iceberg when it comes to odd brain-body activity. All this research has left me thinking – who exactly is my sleepwalking self? She propels me forward, reassuring me with the perfect confidence of dream logic. I’ll walk, babble nonsense, and occasionally put myself in danger. What does my sleepwalking self think, as she pushes me closer to the open door, to the unlocked gate? I’ll never know. I might catch a snippet of her thoughts as I ascend through the layers of dreaming towards consciousness, but despite occupying the same physical space, I will never meet her. It’s a little like living with a ghost after all.

Photo by Vladislav Muslakov on Unsplash.