Can sleepwalking be a murder defense?

Lawrence Martin, M.D., FACP, FCCP

Associate Clinical Professor of Medicine
Case Western Reserve University School of Medicine, Cleveland
Board Certified in Pulmonary and Sleep Medicine

from Shakespeare's Macbeth, Act 5, Scene 1:

Enter a Doctor of Physic and a Waiting-Gentlewoman

DOCTOR: I have two nights watched with you, but can perceive no truth in your report. When was it she last walked?

GENTLEWOMAN: Since his majesty went into the field, I have seen her rise from her bed, throw her night-gown upon her, unlock her closet, take forth paper, fold it, write upon't, read it, afterwards seal it, and again return to bed; yet all this while in a most fast sleep.

DOCTOR: A great perturbation in nature, to receive at once the benefit of sleep, and do the effects of watching! In this slumbery agitation, besides her walking and other actual performances, what, at any time, have you heard her say?

GENTLEWOMAN:  That, sir, which I will not report after her.

DOCTOR:  You may to be:  and 'tis most meet you should.

GENTLEWOMAN:  Neither to you nor any one; having no witness to confirm my speech.

Enter LADY MACBETH, with a taper

Lo, you, here she comes!  This is her very guise; and, upon my life, fast asleep.  Observe her; stand close.

DOCTOR:  How came she by that light?

GENTLEWOMAN:  Why, it stood by her; she has light by her continually; 'tis her comand.

DOCTOR:  You see, her eyes are open.

GENTLEWOMAN:  Ay, but their sense is shut.

The answer to the question in the title is: "possibly." While I have never been involved in any legal case where sleepwalking was an issue, the situation is interesting enough to recount a few cases and discuss the problem.

The first recorded case apparently dates to 1846. According to the BBC (as quoted in Wikipedia), there are now 68 known cases of "homicidal somnambulism." When they come to court the defense against murder charge has been on the order of: "I was sleepwalking and therefore, ladies and gentleman of the jury, I was not myself at the time I murdered [her/him]...and so deserve acquittal."

On a more legal basis, the argument has been:
'The defendant was not in his normal state of mind when he committed the act. Sleep walking is a parasomnia manifested by automatism; as such, harmful actions committed while in this state cannot be blamed on the perpetrator.'

The argument has been successful at times. Two of three well know trials for murder while sleep walking ended in acquittal, the other in a conviction for murder. Coincidentally, two of the trials (one conviction, one acquittal) occurred in the Phoenix area, and were tried in the same legal jurisdiction (Maricopa County Superior Court). I will present those three cases,  plus a non-murder sleepwalking defense case from Australia.


In 1981 a Scottsdale, Arizona man named Steven Steinberg was accused of murdering his wife, Elena, with a kitchen knife. She was stabbed 26 times. The trial took place in Maricopa County Superior Court in 1982. Steinberg acknowledged the murder, claimed he did it while sleepwalking, and therefore was not sane at the time. Dr. Martin Blinder, a California psychiatrist, testified that the murder was committed under a scenario of "dissociative reaction," when Steinberg stabbed repeatedly stabbed his wife.

Steinberg didn't deny the fact that he had killed her, but he pleaded 'not guilty' because he claimed not to remember the crime. He was sleeping, and must have been sleepwalking at the time. Steinberg was found innocent by the jury, on the ground he was temporarily insane when he killed his wife. He walked away a free man.

Should Steinberg have gone to jail? Whether or not he remembered the act, he had murdered his wife. Was the fact he did it while asleep a rational defense? Was it even true? Diana Lindstrom-McClure, part of Steinberg's legal team, believed him. In a newspaper article she was quoted as saying she doesn't feel that he pulled the wool over anyone's eyes. "He was just a nice guy," she said.

Members of the jury were quoted as stating they made the correct decision. Even though they knew they were letting a murderer go, they felt they had no choice. They believed Steinberg was sleep walking and therefore not responsible.

But why did he go free? If he was "temporarily insane" at the time, was he "sane" at the time of trial? As explained in a 1998 Phoenix New Times article:

Many people who were in Arizona in the early 1980s recall Arizona's most famous-- or infamous--"sleepwalking" case. In that one, Scottsdale resident Steven Steinberg stabbed his wife, Elana, 26 times, then told police that intruders had killed her during a burglary gone awry. But the evidence implicated Steinberg, and police arrested him on a murder charge. At trial, his attorney called witnesses to testify that Steinberg may have been sleepwalking or in a short-lived "dissociative" mental state when he stabbed his wife.

Defense attorney Bob Hirsh alleged that Steinberg's "Jewish American Princess" wife had driven him mad with nagging and spending too much money. A jury found Steinberg not guilty on the grounds that he was temporarily insane when he'd killed her. Because he was deemed "sane" at the time of his acquittal, Steinberg walked out of court a free man.

Things are different now under Arizona law. Since 1994, judges have had to impose "guilty but insane" sentences in cases that formerly fell under the old "temporary insanity" model. These days, a person found guilty but insane must serve a sentence at a mental institution that may be as long as if they were sentenced to prison.


Kenneth Parks, a 23-year-old Toronto man with a wife and infant daughter, was suffering from severe insomnia caused by joblessness and gambling debts. Early in the morning of May 23, 1987 he arose, got in his car and drove 23 kilometers to his in-laws' home. He stabbed to death his mother-in-law, whom he loved and who had once referred to him as "a gentle giant." Parks also assaulted his father in law, who survived the attack. He then drove to the police and said "I think I have killed some people . . . my hands," only then realizing he had severely cut his own hands. Under police arrest he was taken to the hospital where he underwent repair of several flexor tendons of both hands.

Because he could not remember anything about the murder and assault, had no motive for the crime whatsoever, and did have a history of sleepwalking, his team of defense experts (psychiatrists, a psychologist, a neurologist and a sleep specialist) concluded Ken Parks was 'asleep' when he committed the crime, and therefore unaware of his actions. To quote from a medical review of the case, Homicidal Somnambulism:  A Case Report (Broughton, et al.  Sleep 1994;17:253-64):

Parks' sleepwalking defense proved successful and on May 25, 1988, the jury rendered a verdict of not guilty. Subsequently Parks was also acquitted of the attempted murder of his father-in-law. The government appealed the decision and in 1992 the Canadian Supreme Court upheld the acquittals (R v. Parks, August 27, 1992).

One defense expert was Dr. R. Billings, a psychiatrist from the University of Toronto, Ontario. The following exchange is taken from Dr. Billings' testimony (Quoted from: E Law - Murdoch University Electronic Journal of Law, Vol 3, No 1 (May 1996) , by Peter Ridgway.)

Q. Do you have an opinion as to whether or not ... Mr. Parks was suffering from any medical illness?

A (Dr. Billings). No.

Q. Dealing now with sleepwalking, from the perspective of general psychiatry, is sleepwalking viewed as a neurological disease?

A. No.

Q. Is it viewed as something that is causally related to mental illness?

A. Can cause mental illness?

Q. No, is sleepwalking .. a result of mental illness?

A. No.

Q. Is sleepwalking a part of any mental illness?

A. No.

Q. In your opinion, ..., is sleepwalking a disease of the mind?

A. No, I would not call it a disease.

...Q. Is there any evidence that a person could formulate a plan while they were awake and then in some way ensure that they carry it out in their sleep?

A. No, absolutely not. Probably the most striking feature of what we know of what goes on in the mind during sleep is that it's very independent of waking mentation in terms of its objectives and so forth. There is a lack of control of directing our minds in sleep compared to wakefulness. In the waking state, of course, we often voluntarily plan things, what we call volition - that is, we decide to do this as opposed to that - and there is no evidence that this occurs during the sleepwalking episode. There usually is - well they are precipitated. They are part of an arousal, an incomplete arousal process during which all investigators have concluded that volition is not present.

Q. And assuming he was sleepwalking at the time, would he have the capacity to intend?

A. No.

Q. Would he have appreciated what he was doing?

A. No he would not.

Q. Would he have understood the consequences of what he was doing?

A. No, I do not believe that he would. I think it would all have been an unconscious activity, uncontrolled and unmeditated.

According to Ridgway, the Canadian Supreme Court substantially adopted, from Dr. Billings, these findings of fact:


In 1997 another Phoenix man, 43-year-old Scott Falater, was accused of murdering his wife. On the night of January 16, 1997, neighbor Greg Koons saw Mr. Falater hold his wife's head under water. Not clear on what was going on, but having heard screaming, Koons called the police. The police arrived to a gruesome crime scene -- a bloodied pool and Mrs. Falater dead with 44 stab wounds. Scott Falater, present at the crime scene, with blood on his neck and band-aids on his hands, was brought to the police station to undergo questioning. He denied any knowledge of the brutal murder and thus began his celebrated sleepwalking defense. Police video from the night of the murder shows Falater saying he is unaware why he is being questioned.

Like Steinberg before him, Falater claimed he had been sleepwalking at the time of the murder. Also like Steinberg, he acknowledged the murder, but said he remembered nothing about what happened; he was asleep at the time. "He was sleepwalking at the time the event occurred and he had no consciousness operating in his mind at the time, in fact, his brain was, in fact, asleep," said defense attorney Michael Kimerer during opening statements at the murder trial.

Prosecutor Juan Martinez told a Maricopa County Superior Court jury that Falater "had an agenda" when he stabbed his wife, Yamila, 44 times. According to the prosecution, the defendant changed clothes and placed his bloodied clothing along with the murder weapon -- a hunting knife -- in a Tupperware container. He then put the container in a trash bag with his boots and socks and stashed the bag in the spare tire well in trunk of his car. After he killed her he took ... all of the items that showed that he was the person that actually killed her and he hid them," said Martinez. Prosecutors said when police searched Falater's Volvo, they found "one neat little package" of evidence, including the gloves.

In this case there was also an eyewitness: his neighbor. After hearing moaning, the neighbor saw Falater pull on gloves, drag the body over to the pool and roll it in. He said he saw Falater hold his wife's head under water and then the neighbor called 911.

Defense attorneys did not dispute that Falater killed his wife of 20 years and the mother of his two children. But Attorney Kimerer said the evidence would show that Falater should be acquitted because he was sleepwalking when the murder happened.

Dr. Rosalind Cartwright, a sleep disorder expert who examined Falater, said it was possible. "Sometimes they hurt themselves. Sometimes they hurt other people. But this is a state in which they are confused. They're not conscious. They think something terrible is happening and they have to defend themselves so, often, they will fight," she told CNN.

The defense argument was that sleep tests conducted on Falater showed he fit the profile of a sleepwalker and had a history of sleepwalking. Kimerer said Falater was undergoing severe stress related to his job as a product engineer at Motorola, sleeping only two or three hours per night at the time.

As the defense explained it, Falater returned home from work on the night of January 16, 1997, had dinner with his family and tried to fix a faulty pool pump. After getting his tools -- including the knife -- and work clothes out of the Tupperware container in the trunk of his car, he decided to do the repair later, Kimerer said. Kimerer said Falater went to sleep exhausted. His explanation for what happened next was that Falater was trying to fix the pool pump as he was sleepwalking and reacted in a rage when his wife came across him. Kimerer called Falater's actions after the killing "nonsensical and illogical," which he said were typical of a sleepwalker.

Testifying after opening arguments, neighbor Koons said Falater's motions appeared fluid and natural. Kimerer said Koons stated before the trial that Falater appeared "robot-like and mechanical," but Koons denied he used those words.

The prosecution and defense also portrayed differing views of the relationship between Falater and his wife. Prosecutors hinted at marital discord over the family's Mormon religion, with Yamila wanting to be less involved with the church. The defense, however, said the two were "soulmates" and there was no discord at all in the marriage.

At the trial two experts backed his story. Then on June 16, 1999 Falater testified on his own behalf. Falater was asked about the gloves he put on after he stabbed his wife but before he dragged her body to the pool. Would he have thought to wear gloves if he were sleepwalking? On the other hand, if this were premeditated, wouldn't he have put them on before the stabbing?

On June 18, 1999 a prosecution expert testified that Falater's actions were "too complex" to have been carried out during sleepwalking.

On June 25, 1999 the jury returned its verdict: Guilty of First Degree Murder. On January 10, 2000 Scott Falater was sentenced to life imprisonment with no chance of parole.

For more on the Falater case, see:
A Killer Sleep Disorder - Phoenix New Times
Homicidal somnambulism in silent movies - Phoenix New Times
Phoenix New Times 2002: Appeals Court Upholds Conviction


Less dramatic, but no less interesting, is the sleep walking defense when murder has not been comitted. In 1996, in Queensland Australia, a man named Burgess hit a woman in the head with a bottle and tried to strangle her. She was injured, but not fatally. Burgess' defense was that he had been sleepwalking at the time. Burgess was found not guilty just as Parks and Steinberg were, but this time the accused was found not guilty by reason of insanity. In Burgess' case, the sleepwalking and the resulting violence were deemed not normal. The following discussion of this case is from E Law - Murdoch University Electronic Journal of Law, Vol 3, No 1 (May 1996) , by Peter Ridgway (this article quoted also in the Parks case).

The contrast in the nature and quality of the evidence between Burgess and Parkes is interesting. Burgess was charged with wounding with intent. During the night, he had hit a woman on the head with a bottle, then with a video, and grasped her by the throat. She suffered some wounds. He claimed he lacked mens rea because he was sleep-walking at the time. A ruling by the trial judge had precluded him from raising a defence of automatism without involving an issue of insanity. He was found not guilty by reason of insanity. 17. In Burgess, the court had been referred to the earlier Canadian Supreme Court decision in R v Parks and noted that a number of witnesses, including experts in sleep disorders, had there given evidence to the effect that sleepwalking is not regarded as a disease of the mind, mental illness or mental disorder.

"We accept of course that sleep is a normal condition, but the evidence in the instant case indicates that sleepwalking and particularly violence in sleep, is not normal ...That case apart (R v. Parks), in none of the other cases where sleepwalking has been mentioned, so far as we can discover, has the court had the advantage of the sort of expert medical evidence which has been available to the judge here." That was, in part, a reference to the evidence of Dr. Peter Fenwick, consulting neuropsychiatrist - who is, arguably without peer in the field - which had been led by the Crown in the trial. A psychiatrist called by the defence in Burgess was a Dr. d'Orban, consulting forensic psychiatrist, who said:

"On the evidence available to me, and subject to the results of the tests when they become available, I came to the same conclusion as Dr. Nicholas [a consultant psychiatrist] and Dr. Eames [a consultant neuropsychiatrist] whose report I have read, and that was that Mr. Burgess' actions had occurred during the course of a sleep disorder."

He was asked by counsel:

Q. Assuming this is a sleep associated automatism, is it an internal or external factor?
A. In this particular case, I think that one would have to see it as an internal factor.
Q. Would you go so far as to say that it was likely to recur?
A. It is possible for it to recur, yes.
. He was asked by the judge:
Q. Is this a case of automatism associated with a pathological condition or not?
A. I think the answer would have to be yes, because it is an abnormality of the brain function, so it would be regarded as a pathological condition."

Dr. Fenwick's evidence was that this was not a sleep-walking episode at all but he described the features of sleepwalking as commonly including violence - although extreme violence is rare; the propensity for severe violence to recur is there. He opined that persons suffering from the disorder should be detained in hospital "because it is a treatable condition."

The Court of Appeal accepted that evidence (taken with the other defence psychiatrist, Dr. Eames) as properly leading to a conclusion that Burgess was:

".. suffering an abnormality or disorder, albeit transitory, due to an internal factor, whether functional or organic, which had manifested itself in violence. It was a disorder or abnormality which might recur, although the possibility of it recurring in the form of serious violence was unlikely. Therefore since this was a legal problem to be decided on legal principles, ... on those principles, the answer was as the judge found it to be."

The legal decisions in the Burgess have been summarized in an web site (no longer accessible) as follows:

1. A person is not criminally responsible for an act or omission which occurs independently of the exercise of his will or an event which occurs by accident.

2. No act is punishable if it is done involuntarily; and an involuntary act in this context - some people nowadays prefer to it as 'automatism' - means an act which is done by the muscles without any control by the mind, such as in spasm, a reflex action or a convulsion; or an act done while suffering from concussion or whilst sleep-walking.

However, in Burgess' case, it was judged that the violence didn't match the situation, that there was the possibility of a recurrence during other episodes of sleepwalking. It was, therefore, deemed a "disease of the mind." In other words, insanity.

Legal and Medical Perspective

To put sleepwalking murder in some perspective I quote below the opening paragraphs of another paper that was published on-line (since removed and not, apparently, in print):

Sleepwalking - Nightmare for the courts, by Ayako Kado and Larry R. Fisher, University of Colorado International English Center, May 9, 2000.

Dr. Kryger says, "We don't know everything there is to know about sleepwalking. In 10 years, maybe we'll find out he was telling the truth. You need to be King Solomon to figure it out." "He" is the person who stabbed his wife to death while, he claimed, sleepwalking. He was found guilty of murder in the first degree. Sleepwalking as an excuse for criminal conduct has brought the courts a "big headache." The dilemma for the legal system involves the decision about whether the sleepwalker should be acquitted or convicted of the crime. Juries need the wisdom of King Solomon to undo this "knotty problem."

There are many anecdotal stories about sleepwalking. Sleepwalking reminds many people of amusing episodes. However, it is not a laughing matter for some people. When sleeping, some sleepwalkers attempt suicide. Some binge on food or become violent to others. Sleepwalkers have even murdered people during their episodes even when the perpetrators had no reason to kill the victims.

The verdicts of the courts have not been universally consistent with each sleep-related violence case. Some sleepwalkers have been found guilty, and some have been set totally free. There is a case in which a man fatally shot his wife and insisted that he remembered nothing about the event. He said his actions must have taken place during a confused arousal caused by his severe sleep apnea in which patients stop breathing during sleep and them suddenly restart breathing with a hoarse snore. The jury rejected this defense and found him guilty of first-degree murder. In a contrasting case, the jury ultimately found a man who had severe sleep apnea and night terrors and killed his wife innocent after two convictions. By their nature, the murder cases involving supposed sleepwalking are of medical and legal interest. In fact, sleepwalking as a criminal defense has opened up considerable debate within both the medical and legal communities. For one example, the medical issue surrounding sleepwalking involves the genetic and organic nature of the condition, in which the sleepwalker is not personally responsible for the conduct. As for the legal profession, the extent to which the sleepwalker's behavior seems to be sane or insane is a major issue.

Further Comment and Conclusion

Sleepwalking is not the only sleep-related defense against murder. The case referred to above, of a man who shot his wife and then claimed he did it on an arousal from sleep apnea (and therefore not under willful control), is well summarized in a medical article from the journal Sleep: Homicidal behavior and sleep apnea: a case report and medicolegal discussion. Sleep 1995;18:776-82. In that case the defendant suffered from respiratory failure, sleep apnea and obesity. He did not sleepwalk.

Sleep walking appears to be the most frequent sleep disorder invoked as defense against murder. In three of the four cases discussed above, the claimant was acquitted of the crime, and in two he walked free - free even of the stigma of being declared insane. In the fourth, the assault case from Australia, sleep walking was declared not normal and therefore a disease of the mind, i.e., the defendant was insane.

Clearly the outcome in an individual case will depend on the details, the jurisdiction, the expert testimony, and other imponderables. Four questions to be asked and answered in any individual case are:

1. Did the defendant commit the crime? To have a sleepwalking defense, the answer must of course be yes. Go to No. 2.

2. Was the defendant sleepwalking at the time? This answer will depend on a) the defendant's own testimony and b) testimony of the experts. If the answer is Yes, go to No. 3. (If no, it is not a 'sleepwalking' defense.)

3. Is the defendant sane at the time of trial? If the answer is yes, go to No. 4. If no, the defense is likely based on a 'not guilty by reason of insanity' plea. Sleepwalking would be additive to the main plea but not the principal defense. At this point it is established that the defendant committed the act, that he was sleepwalking at the time, and that he is sane at the time of trial.

4. Should the defendant go free, go to a mental hospital, or go to jail? Everything presented at court will revolve around one of these three possible outcomes - the defense wanting mainly the first, the prosecution wanting mainly the third, and either side perhaps opting for the middle ground (mental institution) depending on how strong or weak they perceive their case. Here the answer will depend on:

- details of the crime
- expert testimony
- jury makeup, biases, education and background
- judges' interpretations of law (particularly at the appellate level)

Given these variables, anything can happen with a sleepwalking defense. Stated another way, the same four cases cited above - Steinberg, Parks, Falater, Burgess - could have each ended differently if tried in a different year, a different jurisdiction, with a different jury, a different panel of experts, or before a different group of judges. This observation is not insightful, but merely a reflection of reality.

Sleep Home Page/ Internet Sleep Links/ Books about sleep disorders (with links to Index of Dr. Martin's web sites
Forward any comments to:

Copyright © 2009, Lawrence Martin, M.D.