Deputy Labour leader Tom Watson has refused to apologise for calling on police to investigate former Conservative home secretary Leon Brittan.
Watson has been facing growing criticism for demanding police investigate claims that Brittan was involved in a Westminster child abuse ring since it was revealed last week that the first person to make the allegation had admitted that he made it up "as a joke".
In the House of Commons on Monday, Conservative MP Nicholas Soames said Watson had "vilely traduced" Brittan.
But Watson defended his actions, insisting that it was children who had been abused who "[deserve] an apology" from politicians.
"We've presided over a state of affairs where children have been abused and then ignored, dismissed and then ignored. If anyone deserves an apology, it's them," he said.
Watson said he was simply carrying out his duty when a number of people told him alleged that Brittan was involved in child abuse – and some victims had claimed that the police were not following up on inquiries. He said:
"I understand that Honourable and Rt. Honourable members feel aggrieved that Leon Britton was interviewed by the police and that they're angry with my use of language.
"I'm sure they will also agree that when anyone is accused of multiple sexual crimes by numerous, completely unrelated sources, the police have a duty to investigate, no matter who it is.
"My letter was prompted by Jane [a woman who complained to Watson]'s concerns that procedures were not followed. it's not for me to judge the validity of these claims but I believe I was right to demand the guidelines were adhered to.
"I also believe that very many victims in this country have been too terrified to speak out for too long and it's not all over just because a few famous people have gone to prison and it hadn't all gone out of hand because a few people in high places are scared."
Earlier on Monday, David Cameron told LBC radio that Watson had "questions to answer" over his role in the Brittan investigation and said he should "examine his conscience". But Watson told the Commons that parliamentarians needed to examine their consciences for ignoring victims for years.
On Friday, Watson conceded that he had been wrong to say that Brittan was "as close to evil as any human being can get".