DNA confirms a man who passes a polygraph test is a murder suspect in a 1979 cold case.

After 45 years, California authorities were finally able to tell the Gonzalez family who they believe killed their loved one. The Riverside County Sheriff’s Office used DNA and forensic genealogy to identify the alleged killer, who turned out to be the same person who tipped off authorities to the discovery of Esther Gonzalez’s body.

On February 9, 1979, 17-year-old Gonzalez was walking to her sister’s house in Banning, California, about 85 miles east of Los Angeles. She never made it home.

Her body was found the next day in a snowpack near a highway near Banning, the Riverside County District Attorney’s Office said in a news release. She was attacked while walking, raped and beaten to death, authorities said.

Deputies described the unidentified man who found the body as “questionable,” according to the news release. The man, later identified as Lewis Randolph “Randy” Williamson, called the county sheriff to report the body and said he didn’t know whether it was a man or a woman. Sheriff’s investigators later asked Williamson to take a polygraph test.

The district attorney’s office said he agreed to take the test and passed, which “cleared him of any wrongdoing at that time,” according to the news release.

Nearly five decades later, the district attorney’s office said a cold case homicide team used forensic genealogy to confirm Williamson as Gonzalez’s suspected killer.

Forensic genealogy is growing rapidly across the country as investigators analyze DNA in addition to traditional genealogy research to find leads in unsolved cases.

Jason Corey, chief investigator for the Riverside County Sheriff’s Office, said the technique is a huge addition to an investigator’s toolbox.

“I think this will be a great investigative tool in the future,” Corey said. “This will help do a lot of good and not only identify victims, but also point investigators in the direction of their investigations that will help bring these suspects to justice.”

Even after Gonzalez’s case went cold, Riverside County detectives continued to search.

The homicide squad continued to investigate the case for decades after Gonzalez’s death. The team loaded a semen sample from the crime scene into a combined DNA indexing system, but no leads emerged.

In 2023, detectives sent various clues to a genetics laboratory in Texas that specializes in forensic genealogy and identifying victims of unsolved murders.

Earlier this year, a crime analyst laid out all the facts of the case.

Then the light went out.

“Although Williamson was apparently exonerated using a polygraph in 1979, he was never exonerated using DNA because the technology had not yet been developed,” the district attorney’s office said.

Another polygraph was not possible because Williamson died in Florida in 2014.

However, during the autopsy, a blood sample was taken from him.

Florida authorities sent the sample to the California Department of Justice, which confirmed that Williamson’s DNA matched a sperm DNA sample obtained from Gonzalez’s body.

Corey said the case has been in the Riverside County Cold Case Unit since it was filed about five years ago. Several investigators worked on the case over the years. It all ended this Wednesday.

“I can’t imagine what it’s like for them,” Corey said. “This whole family has been devastated over the years. This happens day after day, day after day. I don’t think it’s gotten any easier for them over time.”

“I don’t know if you can say you’re happy it happened because it’s still a terrible tragedy, but I hope it can bring them some closure,” Corey said.

According to Esther’s older sister Elizabeth, the latest developments in the cold case are truly bringing peace and tranquility to the Gonzalez family. She was glad to hear that her sister’s alleged killer had finally been identified.

“We are very happy to finally close,” Elizabeth Gonzalez, 64, wrote in an email to CNN. “We’re happy about it, but since the guy died, it’s a little sad that he won’t take the time to kill her.”

Esther and Elizabeth Gonzalez grew up very close because they were only one year apart in age. The family now remembers Esther for her shy but cheerful and gentle nature. She is the fourth of seven children.

Esther’s older brother, Eddie, wrote on Facebook: “The Gonzalez family would like to thank the Riverside County Sheriff’s Department for a job well done after 40 years of shutting down the Gonzalez family.”

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