Natalie Elphicke, the new Labour MP for Dover, has been accused of lobbying ministers over her then-husband Charlie’s sexual assault case.
Ms Elphicke is accused of asking Sir Robert Buckland, the then justice secretary, to help move the date of the case, apparently to avoid publicity.
A spokesman for Ms Elphicke, who defected from the Conservatives last week, said the claims were “nonsense”.
Labour questioned why they were not raised earlier.
Sir Robert told the Sunday Times, external: “She was told in no uncertain terms that it would have been completely inappropriate to speak to the judge about the trial at all.”
The BBC has confirmed Sir Robert’s account with him.
Labour MP Jonathan Ashworth questioned the timing of the accusations on the BBC’s Sunday With Laura Kuenssberg programme.
“I don’t understand why the Lord Chancellor at the time did not raise this and why he’s raised it now,” Mr Ashworth said.
Foreign Secretary Lord Cameron was also asked about Ms Elphicke on the programme.
He said he had not examined the story closely, but was of the opinion that the fact that Labour welcomed in a person with little affiliation for the party spoke volumes about party.
“All I know is that Natalie Elphicke’s defection said a little bit about Natalie Elphicke, but I think it said rather a lot more about the Labour Party,” he said.
Charlie Elphicke’s trial was due to be one of the first cases after Covid restrictions were lifted in courts which, potentially, could have meant a greater focus on the case.
He was jailed in 2020 at Southwark Crown Court for two years for sexually assaulting two women.
Ms Elphicke replaced her ex-husband as MP for Dover after he was charged, and announced that their marriage was ending after he was convicted.