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Robert Bierenbaum

A former plastic surgeon who was convicted in 2000 of murdering his wife back in 1985 confessed to her killing last year, more than three decades after her death.

Robert Bierenbaum admitted to killing wife Gail Katz and throwing her body out of an airplane during a December 2020 parole board hearing, according to a new report fromABC News— part of the network’s two-installment20/20special airing Friday at 9 p.m.

Bierenbaum was convicted on circumstantial evidence for killing Katz and throwing her body out of an airplane over the Atlantic Ocean after she disappeared in 1985. He previously maintained his innocence for years and remains in prison on a sentence of 20 years to life. His next parole hearing is scheduled for November 2021.

When asked how he went about killing Katz — whose body has never been found — Bierenbaum said he “strangled” her, adding, “I went flying. I opened the door and then took her body out of the airplane over the ocean.”

Back in Feb. 2000, PEOPLE reported on the story and about how Bierenbaum originally told police in July 1985 that his wife had stormed out of their Manhattan apartment after the pair got into a heated altercation the morning prior. Bierenbaum claimed he assumed that Katz had gone to Central Park to calm down before he reported her as missing, but doubts about his story quickly arose.

When asked about his own whereabouts during the time that his wife had disappeared, Bierenbaum said that he had spent much of the day in the couple’s apartment, leaving only to visit family and friends. Police also said that they couldn’t find anyone who had seen Katz leave the building the day of the pair’s altercation.

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But, months later, authorities discovered that Bierenbaum had driven to a New Jersey airport and piloted a rented plane on a two-hour flight over the Atlantic Ocean within hours of his wife’s disappearance. Katz’s body was never found, however, and Bierenbaum wasn’t charged.

Years later, and after relocating numerous times, Bierenbaum then learned that he was wanted for murder and flew to New York City to turn himself in after police discovered new evidence.

In a Nov. 2000 story, PEOPLE reported that jurors took less than seven hours to find the former surgeon guilty of second-degree murder in his wife’s death, despite police never recovering Katz’s body or any other physical evidence linking her husband to the crime. (Evidence that was provided included proof of Bierenbaum’s violent temper and a flight log prosecutors said he altered in a botched attempt to hide his actions on the afternoon of his wife’s death.)

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During his 2020 parole board hearing, ABC News reported that Bierenbaum’s admittance to killing his wife and dumping her body “shocked everyone,” as it was the precise way in which prosecutors had argued he had committed the crime.

“I was like, ‘Holy s—, are you kidding me?’ " Dan Bibb, one of the prosecutors in the case, told the outlet. “I was stunned because I always thought that that day would never come, that he would own up, take responsibility for having killed his wife.”

source: people.com