OKLAHOMA CITY - In November 2014 we remembered Karen Silkwood, a woman who blew the whistle on Kerr McGee and its alleged unsafe practices at its plutonium plant in Crescent. She ended up dead before she could take her proof to the national media.

While authorities ruled her death an accident, for some, her death still remains a mystery.

"If you want to know who killed Karen Silkwood, you have to ask who benefited from her death?" said Richard Rashke, the author of “The Killing of Karen Silkwood.

Rashke has spent years trying to uncover what he believes really happened to Karen Silkwood.

"It was a crime," he said.

Silkwood died in a November 1974 car crash north of Oklahoma City near Crescent, south of the Highway 33/74 junction.

"I was out pretty well all night that night," remembered Rick Fagan, a former Oklahoma Highway Patrol trooper. "I looked down in the ditch and there's a white Honda."

Fagan responded to the accident and besides a few bystanders, was the first official on the scene.

"Strong odor of alcohol around the car, there was marijuana in her purse," Fagan said.

Fagan officially ruled her death an accident, but Rashke doesn't buy it.

"Karen Silkwood was forced off of the road," Rashke said.

Rashke says the car treads show she was trying to get back on the road. But Fagan stands behind his report.

"There was nothing to indicate any type of spin, there was nothing to indicate any drastic swerves," said Fagan.

There was also a dent on the back of the car. Fagan says it happened when the car was pulled from the ditch by the tow truck. However, Rashke believes another car bumped her.

"Every single fact, evidence, piece of evidence, points to the fact she was shoved off the road," he said. "Why? The answer is very clear, she had documents, and somebody wanted them."

Documents showing alleged evidence of safety violations at Kerr McGee's plutonium plant in Crescent where she worked as a lab technician, working with plutonium filled fuel rods.

"I assumed it was safe," said a co-worker of Silkwood's, who wanted to remain anonymous.

The woman said, like Silkwood, she became contaminated with plutonium.

"I was standing at the end of the box on the clean end of it, and I saw some drips on the floor. It was dripping. About three drops came to the floor and I called it to the supervisor's attention and he said it's nothing, keep working. So we started to keep working and all the alarms went off and that's when I had to go into decontamination and get scrubbed down," the co-worker recalled. “I got what was equivalent to a year's dose in just those few drips."

So, Silkwood went undercover to gather proof of unsafe practices at the plant. Specifically X-rays of plutonium filled rods. She claimed some of the rods were flawed and shipped out anyway.

"OK, talking with Karen Silkwood," said Steve Wodka, with the Oil, Chemical and Atomic Workers Union on a recorded telephone conversation with Silkwood.

"They don't understand Steve, what radiation is," Silkwood said on the recording. "I had to change five gloves, now five of them, mind you, had holes in them."

Silkwood was planning to deliver the evidence she had gathered to a New York Times reporter when she mysteriously became contaminated with plutonium.

"None of this seemed right," said Vicki Monks, former News 9 reporter. "There were rumors from the beginning that Karen Silkwood had been killed intentionally."

Monks covered the Silkwood case beginning with the day officials cleared out her apartment because it was contaminated with plutonium. She said many local reporters didn't know what was going on at the plant, much less what plutonium was.

"What does it mean barrels labelled radioactive being taken out of an apartment?" Monks said. "There were a lot of reporters who wanted to talk to her and Kerr McGee wasn't saying much of anything. The next thing we heard was she was dead."

She was killed in an accident on her way to Oklahoma City.

"Three minutes before she got into a car and drove off, she called the union officials and said I'm on my way, I got the documents, see you soon," said Rashke.

Those documents, though, were never found.

"Did she have documents? Yes. Were some of them dealing with negatives of quality control? Yes. They were spotted. They were seen. And people spoke of them and identified them under oath," Rashke said.

"I don't remember picking anything up and putting it in the car. I don't remember any film. I don't remember any documents," said Fagan. "I was there, that's one thing about it, I was there and they weren't."

"Kerr McGee benefited from this whole thing because it got its documents back," Rashke said.

Even so, there's no proof the company played a role in her death.

"So the mystery again is who? And, I'm going to find out," said Rashke.

Rashke is waiting on 300 more FBI documents.