Serial killer William Suff confesses to murder of teenage mother in 1986 in Southern California

A serial killer convicted of murdering 12 women has confessed to the unsolved murder of a 19-year-old mother in Southern California in 1986.

Nineteen-year-old Cathy Small was found stabbed to death on a South Pasadena street in February 1986, but her case remained unsolved for nearly four decades.

“We believe we are providing the victim and her family with a sense of long overdue justice and closure,” Los Angeles County Sheriff Robert Luna said at a news conference this week.

William Lester Suff, known as the “Lake Elsinore Killer” and the “Riverside Prostitute Killer,” admitted to murdering Small in 2022 after his DNA was found on her clothing. He said she “infuriated him” by slapping his glasses off his face during an argument, Lt. Patricia Thomas said during Tuesday's briefing.

Suff told investigators that Small first met him at a computer repair shop where he worked and agreed to drive him from Lake Elsinore in South Pasadena for $50.

After stabbing her repeatedly in the passenger seat of his car, he admitted to throwing her body on the sidewalk and driving away, Thomas said.

Suff, who is on death row in San Quentin, California, also admitted involvement in other unsolved murders in Riverside County, according to Thomas, but did not identify the victims.

Investigators noticed that the DNA collected during the crime had not been tested. When this was done, Suff's DNA was found on her clothing.

Suff began killing in the 1970s and was sentenced to 70 years in prison in 1974 for the death of his two-month-old daughter in Texas. However, he was paroled in 1984 and moved back to California.

Luna said Suff's confession underscores “second, the power of modern forensic science; second, the amazing, tireless work of our Los Angeles homicide detectives, who I keep saying are the best in the country at what they do; and third, the cooperation and partnership between the agencies.”

“With everything we're talking about today, it's important to remember that something as significant as this is about a victim who lost their life and a family that will never forget that. And I know we never forget that, and that's what makes the teamwork here so great.”

Thomas also read a letter from Small's younger sister, who was 10 at the time of her murder but was unable to attend the press conference because she lives out of state.

“My sister Cathy Small was not a statistic,” she wrote. “She was a protective big sister, a loving mother and a good daughter. Cathy was funny, smart and caring. She had a big heart and would do anything for anyone.”

Small's sister said the 19-year-old taught her how to swim, ride a bike and play cards.

“Whenever I was with my big sister, she took me to church,” she continued. “Cathy was talented, but her life ended before she could even begin to pursue her own dreams.”

She added that Small, who had been working as a sex worker at the time of her murder, had tried to get clean and was no longer using drugs, “but before she could take another step forward, her life was ended.”