Michael, now 78, became embroiled in one of America's most famous - and debated - murder cases after his wife, Kathleen Peterson was found dead at the bottom of the staircase in their home in 2001.
WATCH: Michael Peterson joins Holly and Phil on the This Morning sofa
Many viewers were in disbelief that Michael - who served eight years in prison before he was granted a retrial - had agreed to go on the British daytime show. As someone said: "NOT MICHAEL PETERSON ON THIS MORNING??????"
Others expressed their outrage that producers had given him the airtime, with one writing: "Michael Peterson on This Morning is making my skin crawl." Another added: "Nah! This bloke infuriates the hell out of me. I still think guilty!!"
Michael appeared on the show to discuss his wife's death
Michael's appearance on the show comes amid the airing on HBO Max and Sky's new eight-part drama, which has reignited interest in the 21-old-case. In the series, Oscar winner Colin Firth takes on the role of Michael while Toni Collette plays his ex-wife Kathleen.
Colin Firth plays Michael in the new drama
Meanwhile, the real Michael is now a free man, having submitted an Alford plea to the reduced charge of manslaughter during his 2017 retrial. As a result, he was sentenced to time already served and freed.
Following the retrial, he returned to his home of Durham in North Carolina, moving into a ground-floor two-bedroom condo which his Defence attorney David Rudolf stressed in a statement, has "no stairs".
He has also taken up writing again, penning two books about the case. The proceeds for both memoirs, Behind the Staircase and Beyond the Staircase, have been donated to charity.
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