The Clark County Sheriff’s Office Cold Case Unit is looking for the boyfriend of a woman who was murdered nearly 42 years ago.

Martha Morrison disappeared from Portland in the summer of 1974. She was 17 years old.

Her brother, Mike, was 27 at the time. He now lives in Alaska. He remembers Martha as a free spirit who loved music and was not afraid of travel.

“She had a tendency to just go you know, get in the car, hitch hike and go, which we kinda all did in those days,” he said.

It was a time before cellphones and constant contact with friends and family. It was not unusual to go a few days or longer without hearing from Martha.

But then she stopped checking in with the family.

Later that summer, her body turned up in rural Clark County along with the body of another woman.

But a lack of ID and dental records made a positive identification impossible.

For decades Martha's remains were cataloged as a “Jane Doe.” Nobody knew for sure who the bones belonged to.

Then, five years ago, Mike's wife suggested he put his DNA into a national database along with another one of his sisters and that led to a positive identification.

But by then the case had gone cold.

“It's not easy, police records that are incomplete, medical records that are incomplete. Trying just to find basic records from hospitals or police agencies is really challenging when you're going back that far,” said Detective Sergeant Todd Barsness.

His Cold Case team is looking for Martha's boyfriend, hoping he can add details.

“The boyfriend at this point is not a suspect in this case,” said Sgt. Barsness.

But there's just one problem, no one knows his name.

But they do know he was a welder, slender (between 5-foot-7 and 5-foot-10) and possibly African American.

“So we're reaching out to the public but we're also targeting areas like the shipyards in Portland where iron workers and welders were employed during that time to try and find somebody who may remember or maybe find this boyfriend himself,” said Sgt. Barsness.

Martha’s brother spent much of his adult life trying to live with the mysterious murder of his sister.

He hopes someone will come forward now with answers.

“There's still a lot of us around that are, have some memories and some pictures and stuff and maybe it will click. And I hope they call because its, its about how would you feel about your relatives if this had happened to them."

If you have any information about the boyfriend, police want to hear from you. You're asked to call 503-823-4357.