Valerie Percy

Valerie Percy was a bright and promising 21-year-old woman, known for her radiant smile and unpretentious nature despite her family's prominence. A recent graduate of Cornell University with a degree in French literature, she had spent a year studying in Paris and was an avid listener of Edith Piaf. Friends and sorority sisters remembered her as "a happy, loving, beautiful person" who was "gorgeous to look at and wonderful fun to be around." Valerie, along with her twin sister Sharon, was the daughter of Charles H. Percy, a successful business executive who, in the fall of 1966, was the Republican candidate for a U.S. Senate seat in Illinois. That summer, Valerie had tirelessly campaigned for her father, to whom she was very close, and was planning to pursue a master's degree in international studies at Johns Hopkins University.

The Percy family lived in an elegant 22-room mansion on the shore of Lake Michigan in Kenilworth, one of Chicago's wealthiest suburbs. In the pre-dawn hours of Sunday, September 18, 1966, an intruder broke into the home by cutting a hole in a glass pane of a French door. Around 5:00 A.M., Valerie's stepmother, Loraine Percy, was awakened by the sound of moaning coming from Valerie's room. When she went to investigate, she saw a figure holding a flashlight standing over her stepdaughter's bed. The intruder shone the light in Loraine's eyes, blinding her, before fleeing down the stairs and out of the house. Loraine's screams woke her husband, who rushed to his daughter's room while his wife sounded a loud burglar alarm. He found Valerie horrifically beaten and stabbed, but still clinging to life. She died in her father's arms moments later.

The brutal murder in a village that had never before recorded a homicide stunned the community and the nation. The investigation, led by Kenilworth police and Illinois State Police, was one of the most extensive in the state's history. Detectives pursued more than 1,300 leads and interviewed over 14,000 people. The crime scene yielded little conclusive evidence. A serrated bayonet was recovered from Lake Michigan three days later, and a glove was found near the property, but investigators could never definitively link them to the killer. Though the attack was initially believed to have been a burglary gone wrong, nothing was stolen from the home.

Over the years, several individuals were considered persons of interest. Investigators focused heavily on a pair of professional burglars with ties to the Mafia, Francis Leroy Hohimer and his accomplice, Frederick Malchow. While in prison for armed robbery, Hohimer denied killing Valerie but implicated Malchow, who had died in 1967 during a prison escape. Malchow had reportedly told a cellmate he feared a pair of bloody trousers might connect him to the crime, but by the time police found them, it was too late for conclusive forensic testing. No charges were ever filed against Hohimer or Malchow.

Decades later, a new potential suspect emerged. In a 2013 book, author Glenn Wall identified William Thoresen III, the "emotionally disturbed" son of a wealthy industrialist who lived just a block and a half from the Percys. Thoresen had a long history of violence and illegal weapons possession, and FBI records revealed his own probation officer had suggested him as a suspect. Thoresen, who refused to be interviewed by police about the case, was shot and killed by his wife in 1970; she claimed self-defense, telling jurors he had admitted to killing several people. Kenilworth police later stated that Thoresen was never cleared and his possible involvement is considered "undetermined."

In the wake of his daughter's murder, Charles Percy suspended his campaign for two weeks. He went on to win the election that November, serving three terms in the U.S. Senate. He died in 2011 without ever knowing who killed his daughter. At Cornell, friends and sorority sisters endowed a scholarship in Valerie's name that is still awarded annually, a quiet tribute to the vibrant young woman whose life was cut short.

Nearly sixty years after the shocking crime, the murder of Valerie Percy remains one of the nation's most haunting cold cases. As of September 2026, her killer has never been brought to justice. The Kenilworth Police Department continues to classify the case as open and asks anyone with information to call them at 847-251-2141.