Rape kit DNA leads to cold case arrest
Genetic material from assault in Washington matched to suspect in 1979 California killing.
For more than 35 years, she lay buried in a grave marked “Unidentified Female.”
And for more than 40 years, her alleged killer roamed free, an unidentified suspect in a brutal beating and strangling at a South Lake Tahoe campground.
Now they both have names: The victim, Patricia Carnahan, and the accused killer, Harold Carpenter.
Carpenter’s arrest Wednesday by the El Dorado County district attorney in the 1979 killing was the product of investigative genetic genealogy, with law enforcement in Washington state matching his DNA from a rape kit in a separate crime he allegedly committed to the DNA recovered from Carnahan’s murder scene.
“DNA and genetic genealogy is a big deal,” said Vern Pierson, the district attorney.
Carpenter, 63, had been accused in 1994 of raping a woman in Washington. Though charges were never filed, police took DNA from Carpenter — but it was never tested.
“He was not charged in that. So his DNA sat in a warehouse almost 30 years,” Pierson said.
Without the connection of the two cases, prosecutors in California were left trying to match DNA taken from
the unidentified woman’s body and crime scene to family tree databases such as 23andMe.
They got close to solving the case in 2020, interviewing Carpenter’s uncle, whose DNA closely matched the DNA found at the crime scene, but the case remained cold and no arrests were made, according to Pierson.
This year, the sexual assault kit from the 1994 case was tested as part of the Washington state attorney general’s Sexual Assault Kit Initiative, which began in 2017 when the state received a $3-million federal grant to try to eliminate its sexual assault kit backlog.
Though prosecutors in California have not charged Carpenter with sexually
assaulting Carnahan, they said that a sexual assault kit was taken, which provided them with the suspect’s DNA.
The DNA from the Washington case was uploaded into CODIS — the FBI’s nationwide Combined DNA Index System — where it was linked to the Carnahan case.
“Cases like this illustrate the need to test every sexual assault kit and get their DNA profiles loaded into the federal database,” Washington Atty. Gen. Bob Ferguson said in a statement. “Every untested kit could be a potential break in a cold case.”
Carpenter’s arrest brought a measure of relief for Carnahan’s daughter, who knew her mother had been missing for years but
only discovered she was murdered in 2015.
Carnahan’s identity was uncovered after the El Dorado County district attorney’s cold case unit published photographs of Carnahan’s jewelry in a Jewish newspaper after realizing when her body was exhumed in 2015 that she was wearing a religious pendant.
Carnahan’s daughter caught wind of the article, recognized the jewelry and reached out to authorities. Genetic testing revealed that the long-unidentified murder victim was her mother.
Carpenter was arrested in Spokane, Wash., where he lives, and is being held at Spokane County Jail, where he awaits extradition to California.