When Sleep Problems Become Legal Problems, Neuroscience Can Help

Sleepwalking, sleep driving, and other "parasomnias" can get you entangled with the law.

By + More

How the body got there was a mystery. More than 12 hours earlier, the man had emerged from successful back surgery. Now, clad only in underwear, he was outside, dead, wedged between a generator and a wall. He was six floors below the hospital rooftop. Had he jumped to his death? Had he been pushed? Neither, medical investigators concluded. He'd gone sleepwalking, and his stroll took an unfortunate turn.

"The autopsy showed that there were significant abrasions along this individual's back, which showed that he fell straight down," notes Michel Cramer Bornemann, an expert on sleep problems who is codirector of the Minnesota Regional Sleep Disorders Center in Minneapolis. "Suicide victims don't fall straight down. They jump." Moreover, the man had been barefoot yet not been deterred by the roof's layer of sharp stones. "Sleepwalkers don't sense pain; the sensory neural pathways are essentially off-line," says Cramer Bornemann, who was brought in by a family lawyer investigating the hospital's suggestion that the death was a suicide.

Cramer Bornemann heads up Sleep Forensics Associates, a group that lawyers and law enforcement officials have turned to when investigating crimes that may be explained by a sleep problem. Since they've been together—just over two years—he and his two colleagues have fielded approximately 150 requests for case evaluations, some from as far off as New Zealand. Murder, sexual assault, DUI, child abuse, and "suicide" are just a sampling of crimes they've encountered. All have been suspected of involving sleepwalking, sleep driving, or sleep sex, among other so-called parasomnias—inappropriate, unwanted behaviors that arise during sleep. (About one third of those case referrals involve the alleged influence of the sleep aid Ambien, he says.)

While Cramer Bornemann is noticing an increasing need for the group's input on court cases, he explains that it exists primarily to conduct scientific pursuits. These sleep-disorder cases provide an excellent window into the realm of parasomnias, he notes. Sleep Forensics Associates' approach, he said, isn't unlike that of animal-behavioral researchers who study primates in the wild, hoping to learn which behaviors are genetically determined and which are under conscious control.

Cramer Bornemann tracks every case, every call that comes in, collecting data so that years from now, perhaps in a decade or so, patterns might start to emerge that illuminate the physiologic mechanisms that underlie these bizarre sleep behaviors. "It's an attempt to see the breadth and depth of what's out there," says Sleep Forensics teammate Mark Mahowald, director of the Minnesota Regional Sleep Disorders Center and a professor of neurology at the University of Minnesota Medical School. So far, what's out there has proved "extraordinary," he marvels.

"Millions of Americans have some type of behavioral abnormality [during sleep], a parasomnia," says sleep medicine specialist Carlos Schenck, the third member of the Sleep Forensics group and a professor of psychiatry at the University of Minnesota Medical School. People have climbed out windows, driven for miles, and had sexual affairs in their sleep; they punch, kick, curse, and binge-eat in their sleep. Some of the strangest examples can be found in Schenck's books, Sleep and Paradox Lost, where he details stories—mostly his patients'—like that of the woman who dreamed she was cooking for a dinner party and awoke at 6:30 a.m. to find the table fully set and the meal ready. And that of the woman who woke to find she had sliced up her cat on a cutting board, the girl who sleepwalked to the top of a 130-foot crane without rousing, and the man who nearly snapped his wife's neck as he dreamed he was deer hunting with only his hands as a weapon.

"You don't have to extrapolate very far to connect what we see on a routine clinical basis weekly to saying that 'if this went a little bit further, this could easily have resulted in violent or injurious behavior with legal implications,' " says Mahowald.