Jeffrey MacDonald, convicted of murdering his wife and two children in 1979, has been eligible for parole since 1990.
But the one and only time the former Green Beret surgeon applied for it was in 2005 — after he married longtime family friend Kathryn Kurichh.
“I didn’t want to go to the hearing,” he tells PEOPLE. “But I was newly married — three years at the time with a loving and supportive wife. And I had new attorneys offering encouragement saying, ‘Times are changing and you never know.’ ”
But in order to get parole, he would have had to admit to the murders. That’s something he’ll never do, he says.
• For more on the Jeffrey MacDonald case, watch People Magazine Investigates: The Accused, on Jan. 24 at 8 p.m. and 11 p.m. ET on ID.
“There’s no conceivable force in my life that would make me say that,” he says. “It would mean admitting to a horrible series of crimes. Why would I admit to that? I did not do these things. And I refuse to lower myself to beg for any relief.”
He adds, “I’m going to walk out of prison a vindicated and free man. I’m not going to walk out any other way.”
Despite his refusal to admit guilt, he still went before the parole board.
“When you go to a parole hearing they essentially tell you, ‘We’re not interested in your story of actual innocence. We need you to accept your guilt and profess regret,’ ” he says. “I said, ‘I can’t do that.’ … How could any normal human being say that about himself to walk out on the street? I certainly could not do that.”
MacDonald was ultimately denied parole and told he could not apply again until 2020.
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Despite the disappointment, some positive emerged from the episode: Retired U.S. Marshal Jimmy Britt saw media coverage of the case and, after years of silence, came forward to one of McDonald’s lawyers, Wade Smith, of Raleigh, North Carolina.
Britt said he knew something that could potentially break the case wide open: It had to do with Helena Stoeckley, a drug addict and narcotics informant who, along with boyfriend Greg Mitchell, confessed involvement in the murders to many people over a period of years. (Stoeckley and Mitchell are now deceased.)
Britt said he was present when prosecutor Jim Blackburn allegedly threatened to charge Stoeckley with murder if she testified to this in court, a claim Blackburn denies. Ultimately, Stoeckley testified that she did not know where she was at the time of the murders.
Britt’s claim is now a key part of the “newly discovered evidence” MacDonald’s defense hopes will free him: On January 26, the 4th Circuit Court of Appeals will hear oral arguments on his “actual innocence” claim, which has a high burden for overturning a conviction.
MacDonald has always said he is innocent. Prosecutors are just as adamant that he is guilty and are fighting hard to keep him behind bars. US Attorney John Stuart Bruce declined to comment on the specifics of the case, saying in a statement to PEOPLE: “When cases are pending court proceedings, it is the practice of our office to litigate the case in court — through evidence and argument in hearings and in written filings with the court — rather than through the news media.”
• For more on Jeffrey MacDonald’s case and his efforts to clear his name, subscribe now to PEOPLE, or pick up this week’s issue, on newsstands Friday.
MacDonald hopes he will finally be exonerated — but not at the cost of admitting to the murders.
“I am not going to get out saying a falsehood to the parole commission in order for them to give me a break,” he says. “If it takes me saying, ‘I killed my family’ for me to go home, I’m never going home.
“I personally have made a decision in my life that truth matters,” he says. “And if that decision is correct — truth matters— I will be vindicated. I wish I could tell you when but I can’t.”