A Tory MP has complained to the TV regulator after Phillip Schofield inadvertently showed This Morning viewers a list of names of people accused of being paedophiles.
Rob Wilson, the MP for Reading East, wrote to Ofcom on Thursday afternoon to ask whether it was investigating if ITV had broken the broadcasting code which states subjects of significant allegations must be given a "timely opportunity to respond".
"It has been alleged that at least two people's names were visible when Mr Schofield accidentally showed the card to the cameras," Wilson said.
"According to Mr Schofield his grounds for believing the individuals named on the cue-card to be suspected paedophiles stem from their names appearing regularly during a 'cursory glance at the internet' he had conducted yesterday."
Schofield sparked controversy after he ambushed David Cameron on the This Morning sofa with a list of people alleged to have been involved in child abuse.
Cameron, who was unprepared for the question and did not look at the list, replied that he did not want to see a "witch hunt" against gay people unfold.
"I've heard all sorts of names being bandied around and what then tends to happen is that everyone sits around and speculates about people some of who are alive and some of who are dead," he said.
"There is a danger if we are not careful that this can turn into a sort of witch hunt, particularly about people who are gay, and I'm worried about the sort of thing you are doing right now, taking a list of names off the internet."
Wilson told The Huffington Post UK that Schofield should apologise on air for his judgement "and for putting the reputations of individuals and families at severe risk".
"This could have been a very nasty incident and I'm not sure the limitations were thought through by the programme or presenter," he said.
Wilson said ITV should "ensure their presenters understand their responsibilities with regard to such sensitive issues and listen to and implement any advice from Ofcom following my letter".
Schofield has issued an apology in a statement, stressing that it was never his intention to identify anyone on the list.
"I was not accusing anyone of anything and it is essential that it is understood that I would never be part of any kind of witch hunt," he said.
"Unfortunately there may have been a misjudged camera angle for a split second as I showed the prime minister some information I had obtained from the internet.
"I asked for his reaction to give him the opportunity to make a point which he very clearly made about the dangers of any witch hunt."
The government has ordered an inquiry into allegations that a senior Thatcher-era Tory political figure sexually abused children, and that it was covered up.
The move came after the BBC's Newsnight programme broadcast allegations that the man was part of a paedophile ring that abused boys from the Bryn Estyn care home in North Wales during the 1970s.
Downing Street said the ambush on ITV was "irresponsible" and a "silly stunt".
"This silly stunt has resulted in people's names being put out there. They will want to vigorously defend themselves," a Downing Street source said.
"The prime minister has taken necessary serious action on child abuse allegations. He is also concerned about a separate issue where people are facing an internet witch hunt. It's important allegations are handled properly - and people's reputations are not unnecessarily smeared."
Conservative MP Stuart Andrew, who was a councillor in Wrexham at the time of the original inquiry into the North Wales abuse scandal, criticised Schofield saying it was "a cheap shot".
Andrew said: "Given the serious nature of this whole situation and the real complexity in terms of making sure these victims have the confidence to come forward, I thought it was a very cheap stunt to hand a list to the PM on a TV programme. It is not acceptable to take a cheap shot on something that is so fiercely sensitive.
"Anybody who has got any allegations to make must make them to the police, so they can be properly investigated."
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