Can You Kill Someone While Sleepwalking? Here's What An Expert Says

Someone turns in for the night ends up dead before morning. It’s a scary scenario — one that does happen, as seen on “Sleeping with Death,” airing November 6, at 7/6c on Oxygen, a new series which explores bizarre murders that occurred in the middle of the night.

There are all sorts of unusual sleep conditions that occur at night, though, which raises a provocative question: Can you kill someone while sleepwalking?

The use of the sleepwalking defense in court is rare and not always convincing for the jury. But some experts say that crimes being committed while sleeping is a real phenomenon. The fatal situation has been referred to as “homicidal somnambulism,” according to Michel A. Cramer Bornemann, M.D., lead investigator for the Sleep Forensics Associates (SFA) in Minneapolis. 

Parasomnias is the catchall term for behaviors and experiences that arise before, during, or amid arousal from sleep. That includes sleepwalking, a non-rapid eye movement (NREM) sleep arousal disorder. A figure often cited is that around 4 percent of adults have sleepwalking experiences, although another statistic places the frequency lower at 1.5 percent. During sleepwalking, the brain gets stuck between a sleeping and an awake state. 

Bornemann likens it to a “switching error” on a laptop. That can lead to various behaviors.

“It’s uncommon,” said Bornemann, whose organization studies sleep-related disorders and their forensic implications. “Of these, only a very small percentage would turn violent.”

Location and access to a weapon are key factors in many cases when sleepwalking turns deadly or causes injuries, he said.

“By and large, criminal allegations seen with forensic implications are associated with close proximity ... For the vast majority of cases, violence occurs in instances where the victim just happens to be within arm’s length” of the sleepwalker, Bornemann explained.

Grievous injury and death can be the result if weapons — a firearm, a hammer, a pocket knife — are nearby. (If you have a history of sleepwalking, remove these from a bedroom, the sleep expert advised.)

Bornemann told Oxygen that he worked on a homicide case a few years ago in which a sleepwalking “man reached for a letter opener and actually severed his wife’s carotid artery.”

SFA has reviewed a number of historical sleepwalking case studies on its home site, including the case of 25-year-old California sailing instructor Stephen Otto Reitz. He had a history of sleepwalking and fatally smashed his married girlfriend in the head with a flowerpot and stabbed her in 2001. He was convicted.

In a 1994 case in Pennsylvania, Michael Ricksgers claimed he was sleepwalking when he shot his wife to death. He was also convicted.

A high-profile case using the sleepwalking defense that led to an acquittal was during the Canadian trial for the 1987 murder of Barbara Ann Woods and the wounding of her husband, Denis Woods. 

Kenneth Parks, their son-in-law, apparently sleep-drove to their Ontario home and then fatally bludgeoned and stabbed Barbara, the Chicago Tribune reported in 1988. He also choked Denis, who survived the attack.

Of course, sleep forensics is a growing investigative field, according to Bornemann, whose organization works with both defense teams and prosecutors. 

To learn more about other unusual cases, watch “Sleeping with Death,” airing November 6, at 7/6c on Oxygen.