Humanities › Issues Homicidal Sleepwalking: A Rare Defense Share Flipboard Email Print esthAlto/Matthieu Spohn/Getty Images Issues Crime & Punishment Basics Criminals & Crimes Prevention & Safety Investigations & Trials Serial Killers The U. S. Government U.S. Foreign Policy U.S. Liberal Politics U.S. Conservative Politics Women's Issues Civil Liberties The Middle East Terrorism Race Relations Immigration Canadian Government View More By Charles Montaldo Private Investigator Charles Montaldo is a writer and former licensed private detective who worked with law enforcement and insurance firms investigating crime and fraud. our editorial process Charles Montaldo Updated July 03, 2019 When prosecutors decide to charge a person with a crime, one of the criminal elements that must exist is intent. Lawyers need to be able to prove that the defendant voluntarily committed the crime. In the case of homicidal sleepwalking, also known as homicidal somnambulism, the person cannot be held responsible for their crimes committed while sleepwalking, because they did not voluntarily commit the crime. There are very few cases where a person has been murdered, and the key suspect claims that they were sleepwalking when they committed the crime. However, there are some cases where the defense has been able to prove that the defendant's innocence using the sleepwalking defense. Here are some of those cases. Albert Tirrell In 1845, Albert Tirrell was married with two children when he fell in love with Maria Bickford, a sex worker in a Boston brothel. Tirrell left his family to be with Bickford, and the two began living as husband and wife. Despite their relationship, Bickford continued to work in the sex industry, much to Tirrell's displeasure. On October 27, 1845, Tirrell slit Bickford's neck with a razor blade, nearly decapitating her. He then set fire to the brother and fled to New Orleans. There were several witnesses who identified Tirrell as the killer, and he was quickly arrested in New Orleans. Tirrell's lawyer, Rufus Choate, explained to the jury that his client suffered from chronic sleepwalking and that on the night that he murdered Bickford, he could have been suffering from a nightmare or experiencing a trance-like state, and therefore was unaware of his actions. The jury bought the sleepwalking argument and found Tirrell not guilty. It was the first case in the U.S. in which a lawyer used the defense of sleepwalking that resulted in a verdict of not guilty. Sergeant Willis Boshears In 1961, Sergeant Willis Boshears, 29, was a serviceman from Michigan, stationed in the U.K. On New Year's Eve, Boshears spent the day drinking vodka and beer and had little to eat due to dental work. He stopped into a bar and got into a conversation with Jean Constable and David Sault. The three drank and talked and eventually made their way to Boshears apartment. When Constable and Sault began having sex in Boshears bedroom, he dragged a mattress by the fire and continued to drink alone. When they were finished, they joined Boshears on the mattress and fell asleep. Sault woke up at around 1 a.m., got dressed and left. Boshears fell back to sleep. The next thing he recalled was that he woke up with his hands around Jean's limp neck. The following day he disposed of the body under a bush where it was discovered on January 3. He was arrested later the same week and charged with murder. Boshears pleaded not guilty, stating that he was asleep when he murdered Jean. The jury agreed with the defense and Boshears was acquitted. Kenneth Parks Kenneth Parks was 23 years old, married and with a 5-month old baby. He enjoyed an easygoing relationship with his in-laws. In the summer of 1986, Parks developed a gambling problem and was in a lot of debt. In an effort to get out of his financial problems he used the money in the family savings and began embezzling money from his place of employment. By March 1987, his theft was discovered, and he was fired. In May, Parks joined Gamblers Anonymous and decided it was time to come clean with his grandmother and his in-laws about his gambling debts. He arranged to meet his grandmother on May 23 and his in-laws on May 24. On May 24, Parks claimed that while he was still asleep, he got out of bed and drove to his in-laws' house. He then broke into their home and assaulted the couple, then stabbed his mother-in-law to death. Next, he drove to the police station, and while he was asking for help, he apparently woke up. He told the police on duty that he thought he killed some people. Parks was arrested for the murder of his mother-in-law. The father-in-law somehow survived the attack. During his trial, his lawyer used the sleepwalking defense. It included the readings of an EEG that was given to Parks that produced highly irregular results. Unable to provide an answer as to what was causing the EGG results, it was concluded the Parks was telling the truth and had experienced a sleepwalking murder. The jury agreed, and Parks was acquitted. The Canadian Supreme Court later upheld the acquittal. Jo Ann Kiger On August 14, 1963, Jo Ann Kiger was having a nightmare and thought that a crazed madman was running through her home. She claimed that while she was asleep, she armed herself with two revolvers, entered her parent's room where they were sleeping, and fired the guns. Both parents were hit with bullets. Her father died from his injuries, and her mother managed to survive. Kiger was arrested and charged with murder, but a jury was shown Kiger's history of sleepwalking before the incident, and she was acquitted. Jules Lowe Jules Lowe of Manchester, England was arrested and charged with the murder of his 83-year-old father Edward Lowe, who was brutally beaten and found dead in his driveway. During the trial, Lowe admitted to killing his father, but because he suffered from sleepwalking, he did not remember committing the act. Lowe, who shared a house with his father, had a history of sleepwalking, had never been known to show any violence towards his father and had an excellent relationship with him. Defense lawyers also had Lowe tested by sleep experts who provided testimony at his trial that, based on the tests, Lowe suffered from sleepwalking. The defense concluded that the murder of his father was a result of insane automatism and that he could not be held legally responsible for the murder. The jury agreed, and Lowe was sent to a psychiatric hospital where he was treated for 10 months and then released. Michael Ricksgers In 1994, Michael Ricksgers was convicted of the murder of his wife. Ricksgers claimed that he shot his wife to death while sleepwalking. His lawyers told the jury that the episode was brought on by sleep apnea, a medical condition that the defendant suffered from. Ricksgers also said he thought that he dreamed that an intruder was breaking into their home and that he shot at him. The police believe Ricksgers was upset with his wife. When she told him she was leaving, he shot her to death. In this case, the jury sided with the prosecution and Ricksgers was sentenced to life in prison without the chance of parole. Why Do Some Sleepwalkers Become Violent? There is no clear explanation why some people become violent while sleepwalking. Sleepwalkers who are suffering from stress, sleep deprivation, and depression do seem more susceptible to experiencing violent episodes than others, but there is no medical proof that negative emotions result in homicidal sleepwalking. Because there are so few cases to draw conclusions from, a comprehensive medical explanation may never be available.