Viewers on social media slammed the decision to invite Dr Michael Davidson onto the show, just a day after Morgan attacked trans model Munroe Bergdorf for her views on white supremacy.
The TV host and the model, who was controversially dropped from L'Oreal's campaign after she posted a response to the recent events in Charlottesville, Virginia on her Facebook page, clashed when Morgan accused her of being offensive to white people, and called her comments "a load of nonsense".
Speaking to Davidson on the show which aired in the morning on 5 September, Morgan challenged his guest over his views that homosexuality is a "sin" and a "socially constructed concept".
"You know what we call these people?" he asked Davidson. "We call them horrible little bigots in the modern world. Bigoted people who talk complete claptrap and, in my view, a malevolent and dangerous part of our sociaty. What's the matter with you? Stop talking for a moment. Stop banging on."
Despite Morgan's strong stance against Davidson, the "therapist's" appearance on the show prompted a huge backlash from viewers who branded GMB and ITV "irresponsible" for giving Davidson a platform.
Comedian Julian Clary appeared on the show directly after Davidson and made it clear he was unimpressed by the decision to have him on the show.
Clary, who is openly gay, said: "What he's doing is dangerous. But [Piers] you gave him a run for his money. It's a shame you had him on though, really. It's a shame you gave him airtime."
Morgan defended the show, saying: "I think these people should be challenged. He's clearly doing this thing quietly all the time and it's dangerous."
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Clary responded: "Maybe if you talk to the gay community, you might find a faster path to happiness there rather than denial or bringing the devil into it. That's where I have to disagree."
LGBT equality charity Stonewall tweeted a statement after the show aired which said: "No one should be told their identity is something that can be cured" and linked to its website for further details on the charity's stance on so-called "conversion therapy".
The statement notes that in the UK, all major counselling and psychotherapy bodies, as well as the NHS, have concluded that "converson therapy" is dangerous and have condemned it by signing a Memorandum of Understanding.
A comment sent to The Independent from a Stonewall spokesperson added: "Today Good Morning Britain hosted an interview focused on whether same-sex attraction can be cured. It is difficult to understand the motivation for exploring the topic of same-sex conversion now, when two years ago a host of professional bodies publicly condemned the practice.
"When they made this statement, the professional bodies also underlined the harm that can be done to individuals by suggesting that their same-sex attraction can, or should, be cured. Good Morning Britain's editoriual approach is damaging as it consistently suggests that there is a debate to be had about the validity of identities and experiences. At Stonewall we are fighting for acceptance and understanding of people's differences."
A GMB spokesperson told The Independent: "Dr Michael Davidson was robustly challenged by the GMB presenters about his views on homosexuality on the programme."
In July this year the Church of England called on the Government to ban so-called "gay cure therapies", after a private member's motion saw the General Synod overwhelmingly back a motion that demanded the practice be outlawed.
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