It was two years ago when the murder case of 18-year-old Janie Landers first landed on Oregon State Police Detective Steve Hinkle's desk.

In his 12 years with the state police, Hinkle had investigated several homicides.

But this was his first cold case.

On Thursday, police laid out more details from the decades-old case during a press conference in Salem.

Landers was a patient at Fairview Training Center when she went missing on March 9, 1979. Functioning at the level of an 8-year-old, she struggled with learning challenges and behavioral issues that led to her residency at the now-closed state facility in Salem.

Oregon State Police detective solves 1979 cold case murder of Salem teen

Five days after her disappearance, Landers' body was found along a path near Silver Falls State Park. The spot was an obvious dump site. There were no signs of a struggle, no blood and little physical evidence.

An autopsy revealed she died from blunt force trauma to the head. She had multiple defensive wounds and deep cuts on her neck.

"Janie fought very hard," Hinkle said. "Probably unexpectedly due to her very small stature, but she was a fighter."

Police spoke with four witnesses who spotted Landers talking to a man in a gold-yellow sedan the day she disappeared. Detectives interviewed several suspects and tried to track down the mystery-man in the sedan, but new leads soon dried up and the case grew cold.

"I knew when I got assigned it that there was a low statistical likelihood that we'd solve it ...," Hinkle said. "But I just did it anyway."

For cases like Landers' to be solved, some critical things are needed, said OSP criminal investigations Capt. Jon Harrington.

The first is a vocal, persistent family advocate. Landers' sister Joyce Hooper was only 13 when she was murdered. Hooper repeatedly urged OSP to reopen her sister's case. In 2015, she contacted them again, hoping to find closure while her father was still alive.

Harrington said the next ingredient was a dogged detective.

"Detective Hinkle is extremely hardworking, extremely intelligent," he said. "He put a lot of his own time into this case. He really took it under his wing and brought it to where it was."

Hinkle reviewed Landers' autopsy report. Her body was riddled with deep cuts and defensive wounds. He took a closer look and saw there were no hilt abrasions on her wounds.

With no knife hilt, assailants are more likely to cut themselves during the attack. This meant Landers' killer likely left some of his own DNA on her bloodied clothing.

Advances in forensic science, like being able to single out a minute amount of an attacker's blood on a victim's blood-soaked shirt, also are key in solving cold cases, Harrington said.

The last thing needed, he added, is luck.

Thankfully, they had it. The DNA evidence on Landers' shirt was not degraded. Harrington and Hinkle took it to a Eugene lab for testing.

DNA evidence is a ticking clock, and detecting evidence on Landers' shirt could be like finding a needle in a haystack, he said.

In April 2016, a forensic scientist contacted Hinkle. A blood stain on the shirt matched the DNA of convicted sex offender and former Fairview employee Gerald Kenneth Dunlap.

"The next task was figuring out how Gerald Dunlap played into this whole thing and if he could've been the one that killed her," Hinkle said.

He discovered Dunlap was convicted of raping a woman while robbing a Tennessee laundromat in 1961. He was sentenced to life in prison but released on parole 12 years later.

Dunlap moved to Salem and began working as a laundry employee at Fairview.

After being convicted of sexually abusing a minor female family member in 1996, Dunlap was sentenced to prison. He died at the Snake River Correctional Facility in 2002.

Hinkle confirmed that Dunlap was working at Fairview the day Landers disappeared. He wanted to see if Dunlap matched a composite sketch done of the man last seen with Landers.

"The next thing we were trying to do was get a picture of this guy because the only picture I got of him is as an old man in Oregon Department of Corrections," he said. "That not what he looked like at the time. We kind of struck out everywhere we went on that."

DMV records before 1990 were not available in Oregon or California.

His luck returned when he contacted the Tennesse Department of Corrections. They sent over a mugshot of Dunlap taken before he was released on parole.

The first thing he noticed was Dunlap's striking resemblance to the sketch — his sloped head, his hairline and his eyes were eerily similar.

The Marion County District Attorney's Office determined Dunlap was solely responsible for Landers' murder. The case was solved.

On Monday, Hinkle was able to return Landers' belongings to her family. He presented Hooper, now 52, and her father Richard Landers, 84, with a pair of earrings and two small hair ties.

"I'm glad that we're able to bring the family some closure on this," Hinkle said. "They waited an awful long time to finally figure out what happened to Janie."

Harrington said state police have dozens of cold case homicide investigations waiting to be solved. The longer a case sits, the harder it can be to unravel.

Hinkle said he knew the investigation could be fruitless and frustrating. But he wanted to give it his best shot.

"It needed to be solved," he said. "It was a vulnerable, young girl that got murdered for no reason and somebody did it. Somebody needed to be held accountable."

For questions, comments and news tips, email reporter Whitney Woodworth at wmwoodwort@statesmanjournal.com, call 503-399-6884 or follow on Twitter @wmwoodworth

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