Men Nabbed In 1973 Killings of 2 Girls After Investigator With 'Free Time' Gets Their DNA Tested

State Department of Justice forensic lab technicians found DNA in the semen matched the genetic profiles of cousins Larry Patterson and William Harbour.

The decades-long mystery of who killed two young girls found dead after failing to return from a California mall may finally be solved after DNA from the cold case sent to be tested by an investigator with “a bit of free time” pointed to two now-65-year-old men, officials said.

Valerie Janice Lane, 12, and Doris Karen Derryberry, 13, were reported missing by their mothers on November 12, 1973, after neither returned from a shopping trip to a mall near their Olivehurst homes the day before.

Officials with the Yuba County Sheriff’s Department found the girls’ bodies alongside a dirt road near Camp Far West Lake outside of Wheatland a few hours later. They had both been killed by shotgun blasts at close range, authorities said.

Though investigators poured over evidence and conducted more than 60 interviews over three years, the case remained cold until March 2014, when a Yuba County investigator sent semen samples found on Derryberry’s body for analysis, according to reports.

State Department of Justice forensic lab technicians say they found the DNA in the semen matched the genetic profiles of cousins Larry Don Patterson and William Lloyd Harbour, the Associated Press reported.

“Over time, anyone that’s been assigned to our investigations unit for any length of time looks into some of the unsolved cases that we have,” Yuba County Sherriff-Coroner Steve Durfor told reporters.

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"And this was one in particular that one of our investigators had a bit of free time and really looked very closely at this case and identified that we should send some things off and see what it might yield for us.”

The case was re-opened after the DNA came back a match, and after more than a year of the renewed and expanded investigation, Yuba County Detectives presented the case to the Yuba County District Attorney’s Office, leading to warrants for Patterson and Harbour's arrests, authorities said.

Harbour, who was 22 at the time of the murders, was arrested on Tuesday during a traffic stop in Olivehurst.

Patterson, who was also 22 when the girls were killed, was also arrested on Tuesday in Oakhurst, Oklahoma, Tuesday. He lived in Olivehurst at the time of the murders.

Both men will now face murder charges. 

Each had reportedly committed serious enough crimes since 1973 to have samples of their DNA collected and placed in law enforcement computer systems.

Durfor said that Patterson was arrested in 1976 for raping two women and again in 2006 for failing to register as a sex offender, while Harbour had felony drug convictions, the Associated Press reported.

He commended those assigned to the case for their work since the girls were discovered dead all those years ago, saying: “I got to tell you, great credit is deserving to the investigators involved in the case in 1973.

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“They conducted extraordinary attention to detail a very meticulous investigation, very meticulous handling of evidence and the packaging of vital evidence which preserved key forensic evidence that proved of value today,” he continued. “This was them having the forewarning of knowing such advancements weren't even invented back in 1973 and they didn't know what was on the horizon. And it was pivotal in solving this case today.”

The break in the case was bittersweet for the victims’ families, who had waited 43 years for answers.

“We are still overwhelmed by everything that has [come] to light,” Lane’s sister wrote on Facebook, requesting privacy and thanking loved ones for their thoughts and prayers.

"Waking up this morning, yesterday's news seems so surreal... it hasn't really hit us yet that someone is finally going to pay for what they did to my sister and [D]oris 43 years ago," she continued.

“Justice is good! And it will happen again when the Lord takes over! Lord thank you for finally giving these [families] peace,” a former neighbor of the Derryberrys wrote. “I really hope they will be at peace now.”

Watch: Heartbroken Mom of Murdered 13-Year-Old Remembers Daughter