While Tonya Harding has remained adamant that she was not involved with the planned 1994 attack against skating rival Nancy Kerrigan, not everyone is convinced.

Former Multnomah County deputy district attorney Norman Frink, who headed the Oregon investigation against Harding, tells PEOPLE that Harding, “was involved up to her neck right from day one.”

Tonya Harding and Nancy Kerrigan
| Credit: Pascal Rondeau/ALLSPORT/Getty

Seven weeks before the 1994 Olympic Winter Games, Harding’s skating rival, Kerrigan, was clubbed on the knee by an assailant. A man later identified as Shane Stant struck Kerrigan in the knee with a baton after she walked off the ice in January of that year, during practice for the U.S. Figure Skating Championships.

Though she was injured and briefly withdrew from competition to recuperate, Kerrigan was well enough to compete in the Olympics, where she earned a silver medal in women’s singles while Harding came in eighth.

The attack was arranged by Harding’s ex-husband, Jeff Gillooly, along with Brian Sean Griffith (then named Shawn Eckardt) and his friend Derrick Smith, who drove the getaway car.

Gillooly and Eckhart plead guilty to racketeering for their involvement in the incident. Gillooly was sentenced to two years in prison and a fine of $100,000. Eckardt, Stant and Smith were sentenced to 18 months each in prison with no fines.

Harding denied having any involvement in the attack but pleaded guilty to conspiring to hinder prosecution. She had to pay a $160,000 fine and was sentenced to three years’ probation and 500 hours community service.

In addition, she was banned for life from the U.S. Figure Skating Association.

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“The only reason she didn’t go to prison with the other people, although the quality of evidence was good, it wasn’t as good as the other people,” Frink says referring to the men involved in the attack. “We made a decision, as you do often in criminal cases when you don’t have iron-clad evidence, we made a compromise.”

At the time, Gillooly’s attorney released copies of his client’s interviews with the FBI in which Gillooly said his ex-wife was deeply involved in the conspiracy to injure the skater.

Tonya Harding - Main/Tout
Credit: Phil Sandlin/File/AP

In the accounts of Gillooly’s interview with the FBI, he told agents that on Dec. 28 Harding approved a final plan to assault Kerrigan.

After Harding pressed Gillooly to make a decision, he said, “I think we should go for it,” according to the FBI documents.

“Okay, let’s do it,” Harding allegedly replied.

Tonya Harding - 1
Credit: Multnomah District Attorney

The case against Harding was strengthened by one crucial piece of evidence found in a dumpster: a handwritten note in which Harding had written the address of the skating center where Kerrigan trained in South Dennis, Massachusetts. (That attack didn’t work out, so they had to give it a second attempt in Detroit.)

The note, which was written on the back of an envelope, included the name “Tony Kent Arena,” which was where Kerrigan would be. The address: 8 Gages Way, South Dennis.

Tonya Harding - 2
Credit: Multnomah District Attorney

The envelope was found along with other documents which could be definitively traced back to Harding.

In the film, I Tonya, Margot Robbie, who portrays Harding, begs the judge to send her to jail rather than ban her for life from skating. But Frink, who is now retired, says this isn’t accurate. “She could have gone to prison instead if she wanted to. This is what she wanted to do at the time,” he says. “We would have gladly accepted an alternative sentence where she got the same as everyone else. There’s no point in her whining about the choices she made back then now.”

Frink has not seen the film but did watch the ABC Truth and Lies special in early January, where Harding admitted she “knew something was up.”

When asked in the special if she said to Gillooly to go through with the plot, she says “no.” Harding however says she did “overhear” the assailants talking about how “maybe we should take somebody out so we can make sure she gets on the team.”

“I go, ‘What the hell are you talking about?’ ” said Harding.

“It was a startling admission, because it was the first time she ever admitted something that gets closer to the truth than what she usually says,” says Frink. “With Tonya Harding, the line between truth and fiction is always blurry.”

  • With reporting by ANDREA DAMEWOOD