By Poppy Johnston in Canberra

PETER Dutton has defended his party’s pursuit of answers on the possible use of rape allegations for political gain by Labor.

The federal opposition leader was asked on Wednesday to explain why the coalition is hounding the government, despite concerns the politicisation of the issue is harmful to those involved and could silence similar allegations in the future.

The opposition has been on Finance Minister Katy Gallagher’s case for potentially misleading parliament by suggesting she was not aware of the Brittany Higgins rape allegations before they were made public in 2021 despite leaked text messages pointing to the contrary.

Responding to a delegate’s question at a local government conference in Canberra, Mr Dutton said it was “reasonable” to seek answers from a government that may have conspired to gain political advantage from an alleged sexual assault.

As the councillor labelled the ongoing politicisation of the alleged rape by both sides of politics “disgusting” – a characterisation that drew applause from the crowd – Mr Dutton said it was important to hold the government to account.

“It doesn’t demean the allegation of sexual assault,” the opposition leader said.

“It doesn’t seek to draw innocence or guilt from any party that’s involved in this matter.”

But Mr Dutton said he supported the investigation by the Australian Federal Police into the leaking of Ms Higgins’ private messages to the media.

His colleague Andrew Bragg also voiced his support for the investigation.

“I expect that there will be a proper investigation because, I mean, why would anyone come forward with allegations of assault if this is the result?” the Liberal senator told ABC Radio.

Ms Higgins alleged she was raped by fellow Liberal staffer Bruce Lehrmann inside the Parliament House office of then-minister Linda Reynolds in 2019, a claim he has always denied.

Mr Lehrmann faced a criminal trial which was derailed by juror misconduct.

Prosecutors ultimately dropped the charge due to the impact of a second trial on Ms Higgins’ mental health.

Questions over Senator Gallagher’s conduct were raised after leaked text messages between Ms Higgins and her partner David Sharaz emerged last week, suggesting the pair strategised with her, then in opposition, ahead of the story being published.

Attorney-General Mark Dreyfus told parliament the apparent unauthorised leak of court material provided under subpoena was deeply concerning and an AFP investigation was under way.

He said it was important victims of alleged sexual assault had confidence that if they came forward and reported what happened to them they would be treated fairly by the justice system.

Labor minister Jenny McAllister declined to comment on the AFP investigation, but was also concerned about the politicisation of the matter.

“I have to say that I am a little disappointed in the tone and the approach that’s been adopted in recent days by some commentators,” she said.

The political fallout from the matter continues to escalate as Liberal senator Linda Reynolds threatens to take defamation action against Environment Minister Tanya Plibersek in relation to a television interview that discussed the alleged rape.

The environment minister confirmed she had received an “interesting letter” on Tuesday.

“As far as I’m concerned, all legal options are on the table,” Ms Plibersek said.

Senator Reynolds told AAP that her lawyers had issued a defamation concerns notice to Ms Plibersek  over an interview that aired on Channel 7 on Monday

“Her comments conveyed the defamatory imputations that I acted to conceal or hide the commission of a criminal offence and also that I acted inappropriately during the investigation of the Brittany Higgins’ allegations,” the senator said.

Trial by a media that may have unclean hands