The Violent Life And Death Of Valerie Percy Murder Suspect William Thoresen III

In the early morning hours of September 18, 1966, a woman named Loraine Percy was startled awake by what she described as, "the sound of someone moaning." As reported by Chicago Tribune, Loraine followed the sound to her stepdaughter's bedroom. When she opened the door, her 21-year-old stepdaughter, Valerie, was laying unresponsive on her bed –- which was soaked with blood. A man, who Loraine did not recognize, was bent over Valerie's body with a flashlight in his hand.

Lorain immediately fled the room and woke her husband, Charles. She then called authorities to the house. Although Charles ran to his daughter's room, the intruder had already made his way out of the house and Valerie was clearly dead.

Chicago Tribune reports authorities were unable to determine a motive for the brutal murder, as nothing of value was missing from Valerie's room or the rest of the house. Detectives believe Valerie was asleep when the intruder bludgeoned, then stabbed her to death.

William Thoresen III is suspected of killing 21-year-old Valerie Percy

As reported by Chicago Tribune, authorities launched an extensive investigation into the unusual murder. However, they had little information about the attacker and few, if any leads. Loraine Percy was only able to provide a vague description of the man, who she described as around 5'8 and approximately 160 pounds. She said he had dark hair and was wearing a plaid shirt.

In addition to the brutality of the murder, the case gained national attention as Valerie was the daughter of a wealthy business executive, who was a Republican U.S. Senate candidate at the time of his daughter's murder. Chicago Tribune reports Valerie had just graduated from Cornell University and moved back home to her parents' Kenilworth, Illinois, home, as she wanted to assist her father with his campaign.

Authorities identified several persons of interest in the murders, including a gang of local burglars, but no arrests were ever made. However, in recent years, it has been suggested that Valerie was the victim of a man named William Thoresen III.

William Thoresen III's criminal behavior started when he was a young teen

William Thoresen III, who was born in 1937, was the son of William E. Thoresen II and Catherine Ehrman. As reported by Sun Sentinel, William's father was the founder and president of the Great Western Steel Company, and the family was quite wealthy.

Classic Chicago Magazine reports William Thoresen III, began acting out and behaving unusually during his early teens. He was caught sneaking into the homes of his neighbors on numerous occasions and authorities had warned him against harassing at least one of the families. As they were concerned about his increasingly unusual behavior, William's parents had him admitted to Chicago's Michael Reese Hospital's mental health unit.

William was admitted to several mental health facilities throughout his teens. However, on at least one occasion he escaped and returned home. According to Classic Chicago Magazine, William then locked himself inside his bedroom with a gun and threatened to shoot anyone who tried to open the door.

William Thoresen III married Louise Banich

As reported by The New York Times, William Thoresen III developed a reputation for being an angry and sometimes destructive loner. As he spent a large portion of his teens in boarding schools and mental health facilities, his education was sporadic and he lacked the skills to secure gainful employment. Thoresen also became known to local law enforcement as combative. He was known to vandalize vehicles and to "terrorize young women" (per the NYT).

Thoresen eventually married a woman named Louise Banich. However, the marriage did not inspire him to change his ways. According to The New York Times, it has been suggested that Thoresen married Banich to escape his family's control of his mental health care.

Although Louise admitted she was aware of her new husband's mental health concerns and his criminal behavior, she empathized with his tales of a painful childhood. The New York Times reports she was also intrigued by the fact that Thoresen stood to inherit millions from his wealthy parents.

William Thoresen III and Louise Banich became partners in crime

Instead of discouraging William Thoresen III's criminal behavior, Louise encouraged and enabled him. As reported by The New York Times, Louise's involvement in Thoresen's crimes began with petty theft. She then went so far as to provide him with false alibis and even allowed herself to be arrested so her husband could escape. Later, Louise assisted Thoresen with his involvement in a national illegal arms purchasing and transportation scheme.

Through the years, Thoresen continued to spiral out of control. He began using a variety of drugs, including hallucinogens like LSD. According to The New York Times, Louise said he also forced her to take LSD against her will and raped her while she was incapacitated. When she got pregnant, Thoresen reportedly forced her to get an abortion.

Louise said Thoresen routinely threatened her life. Although she suggested divorce on more than one occasion, he always managed to talk her out of it.

If you or someone you know is dealing with domestic abuse, you can call the National Domestic Violence Hotline at 1−800−799−7233. You can also find more information, resources, and support at their website.

Louise Banich ultimately killed William Thoresen III

Louise said William Thoresen III's threats eventually evolved into more sadistic physical abuse. As reported by The New York Times, Louise said Thoresen struck her with his fists, sliced her with razor blades, and even stabbed her. Louise believed he would eventually kill her, as he also forced her to write suicide notes to her family and friends.

Classic Chicago Magazine reports Louise claimed Thoresen confessed to her that he committed at least three murders, including the shooting death of his younger brother. Louise said the confessions, and her ongoing fear for her own life prompted her to shoot and kill Thoresen in self-defense. According to The New York Times, Louise, who was charged with but acquitted of Thoresen's murder, said, "Despite everything rotten he'd been responsible for in my life, I loved him deeply."

In recent years, it has been suggested that Thoresen was also responsible for the murder of Valerie Percy. UPI reports FBI files, which were obtained by WLS-TV, Chicago, named Thoresen as a suspect in the brutal crime. Investigators noted Thoresen lived fewer than two blocks from the Percy home when the young woman was killed — yet she was not among the three people Thoresen allegedly said he killed, per Classic Chicago Magazine.

According to UPI, they also noted that Thoresen had ongoing mental health concerns, violent tendencies, and had access to multiple weapons. Although authorities did question Thoresen about Percy's death, he denied any involvement, and no concrete evidence linking him to the crime was ever found.