Updated

DNA tests on evidence from the killings of three Girl Scouts in Mayes County more than 30 years ago were determined to be inconclusive, District Attorney Gene Haynes said Tuesday.

Investigators were hoping that DNA evidence collected from the scene would lead investigators to person who sexually assaulted and killed the three girls. But Haynes said tests show that DNA tests of stains found on a pillowcase likely came from the victims.

"It is unfortunate the testing did not produce a DNA profile," Haynes said. "We had hoped the testing would bring an end to the debate over who committed these terrible crimes."

The bodies of Lori Farmer, 8, of Tulsa; Michelle Guse, 9, of Broken Arrow; and Doris Milner, 10, of Tulsa, were discovered on June 13, 1977, at Camp Scott near Locust Grove in a crime that shocked Oklahomans.

Escaped convict Gene Leroy Hart was the prime suspect in the murders, but he was acquitted during a highly publicized trial in 1979. He died in prison of a heart attack two months later while serving time on unrelated charges.

Since Hart's death, a public debate has festered over whether he actually killed the girls.

"There are people with strong feelings that Hart was the right guy but they just weren't able to get a conviction," Haynes said. "Some other people think he was the scapegoat."

In 2007, tests were conducted on semen stains on a pillowcase and from a swab from one of the victims, but chemists were unable to develop a DNA profile. Further tests conducted on a pillowcase stain were determined to have come from a female.

Investigators sought to reanalyze DNA from the victims, but it was determined the samples were too old, so samples were sought from the girls' surviving parents.

Tests on those samples determined the female DNA likely came from the victim, leading investigators down another cold trail, Haynes said.

"We're pretty much at a dead end unless some time in the future they come up with some other kind of testing that might be able to pull DNA out of an even smaller or more deteriorated sample," Haynes said.

While some of the evidence, including the swab from the victim, were destroyed during the testing, Haynes said there is still some physical evidence left. He said family members of the victims were notified of the test results.

"I'm sure they're disappointed, but I think they're just appreciative that people continue to try to find answers in this case."

When the DNA tests were announced last year, Sheri Farmer, Lori's mother, said she refused to fret over the anticipation of the results.

"I'm not sitting around and waiting for it or anything like that," she said at the time. "I never really held out a lot of hope on the DNA to start with. I'm not expecting any miracles."