Jeffrey MacDonald’s Wife Opens Up About Fighting for His Innocence in Family’s Triple Murder

Jeffrey MacDonald has fought a nearly 40-year fight against his murder convictions in the slayings of his wife and two young daughters, in 1970. But he hasn’t been alone in his claims of innocence, which will go before an appeals court later this month.

MacDonald’s wife, Kathryn, has worked alongside Jeff’s friends to advocate for his exoneration. She runs a website about the case. The case was featured on Monday night’s season finale of People Magazine Investigates, on Investigation Discovery.

In an after-show, available now on the People/Entertainment Weekly Network (PEN), Kathryn appeared with Jeff’s longtime friend Rick Thoesen to discuss their support of him despite the fact that prosecutors are certain of his guilt.

Asked what motivates her, Kathryn said during the show it was “the terrible injustice that I see there.”

“The more I to know him and love him, it’d be like, ‘How could you sleep at night?’ ” she continued. “Some things are bigger than ourselves. And I know it’s hard to understand. I wouldn’t wish this situation on anybody, but some things are more important than what might be best for me.”

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Thoesen added, quoting award-winning documentarian Errol Morris, who wrote a book about the case, “Jeff lives in two prisons — one is the prison he’s in now, incarcerated, but the other one is a prison of beliefs, wrong or right.”

“This man is strong,” Thoesen said of his friend of nearly 50 years. “I’ve never seen him come to visit us in prison ‘Woe is me.’ He’s always uplifting, he believes in himself and we believe in him and that’s what drives us.”

Jeff’s legal team will appear in court on Jan. 26 to argue for his exoneration in the deaths of his family, citing what they say is previously unknown forensic evidence — and confessions made by two of the alleged intruders Jeff has always blamed for the killings.

U.S. 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.”