A 37-year-old murder still haunts the detective who first worked the case as well as the victim's brother, who is as determined as ever to get answers.

Lisa Moore was 22 years old, a senior at the University of Tulsa, and by everyone's account, she was a sweet girl from a good family in Muskogee, Oklahoma. She was leaving a sorority event on March 26th, 1984, and she was going to her nearby apartment, when she simply vanished.

But the question remains after all these years: who murdered Lisa Moore?

Lake Moore still talks about his sister, Lisa, with the love and admiration that comes from a little brother to a big sister.

"My favorite thing was to make her laugh,” Lake said. “Her laugh was fantastic. Once she started laughing, she couldn't stop."

Lake and his parents were frantic when they realized Lisa was missing and, for a month, they clung to hope and prayed the news would be good. Until April 17th, when her body was found by bridge workers in rural Mayes County, floating face down in a drainage ditch, badly decomposed, and partially nude.

Her cause of death: homicide by drowning.

"I lost all the blood out of my system," Lake remembered.

The entire family was devastated and it shocked Green Country.

Kevin Otwell, a former OSBI agent recalled how shocking it was.

“It's shocking to your morality, to your values, to find a young girl with her whole life ahead of her, stripped nude and thrown in a ditch," Otwell said.

Then a suspect emerged.

Two witnesses saw a dark El Camino on the bridge where Lisa was found, and both gave descriptions of a suspicious man seen there during Lisa's disappearance.

Another witness described a man she saw park a car in her neighborhood, who then walk away and toss the keys. Police discovered that was Lisa's car which had been abandoned about 24 hours after Lisa went missing, and just two miles from her apartment.

When Otwell went to Lisa's apartment to search for evidence, he met her neighbor—who owned a dark El Camino.

That neighbor said he had seen a man in the backyard hiding behind a tree, wearing a mask, and the neighbor believed it was notorious serial killer Christopher Wilder, and he theorized Wilder had killed Lisa.

"Whenever you try to throw me off in a crime I'm investigating, and you're driving a vehicle similar to one seen where a young lady's body was found, I'm suspicious of you," Otwell stated.

Otwell created a photo lineup, and the two witnesses on the bridge picked out the neighbor. The third witness also picked out the neighbor as the person who looked most like the man she remembered seeing get out of Lisa's car.

"We followed the evidence," Otwell said.

The evidence included hairs found in Lisa's car and on her bedding; so, Otwell got a search warrant for the neighbor's hair and suspicions grew.

With high hopes, Otwell and the Moore family met with then Tulsa County District Attorney David Moss, and they laid out the case.

"We thought we were going in there to get some good news, and it was the biggest let down of our lives," Lake stated.

Moss told them the evidence was not enough. The Mayes County District Attorney said the same.

But there was a glimmer of hope. The D.A. said if the witnesses can pick him out of a real-life lineup, maybe he would file the case; but the witness was not able to do that—and just that quick—hope was gone.

“It was two steps forward and one step back," Otwell shared.

The D.A. asked the family to be patient, that DNA was just a few years away and that would seal the deal.

But as years passed, Lisa's parents and the witnesses from the bridge died, with no new information about that DNA. So what happened to it?

"We've never gotten any straight answers about that. To this day, I would like to know, has it ever been tested? Do we even still have the DNA or has the DNA been compromised someway?" Lake asked.

"Why do you think you can't get a straight answer?" Lori Fullbright asked.

"I can't answer that Lori, I wish I could, but I don't know why,” Lake said.

“It's an unknown profile and we have no idea,” Tulsa cold case detective Eddie Majors said.

Majors given this case in 2014.

He said the DNA found in this case was tested by OSBI but wasn't sure when. He said it was entered into CODIS, the national DNA database at some point, but there's never been a match.

Majors said even though the neighbor's DNA is not included in the database, somewhere along the line, the neighbor was excluded as a suspect.

“So, he has actually been excluded based on DNA?" Fullbright asked.

"Based on that particular piece of evidence, yes,” Majors said.

That was stunning news to Lake. He and former OSBI agent Otwell said they've both talked to detective Majors over the years and were never told the neighbor had been cleared.

Regardless, Majors said, nobody is ever ruled out in a homicide investigation. There's no statute of limitations and new science could develop, or someone could come forward with key information.

Several suspects have been ruled out including serial killer Christopher Wilder who the FBI said only made it to OKC and serial killer Gary Allen Walker, who killed several women in this area during that time frame as well.

OSBI said they couldn’t answer questions about the DNA because the agency is excluded from the state’s open records law.

Lake said his parents died before getting answers and he doesn't want that to happen to him too.

"This horrible murder is not stuck in 1984, this, this event is carried to present day,” Lake said. “One thing that pains me more than anything is my kids have never been able to know their aunt."

Anyone with information can call OSBI and Tulsa Police.