The opposition has sharpened its attack on Katy Gallagher as the finance minister doubles down on her assertion that Labor did not leverage Brittany Higgins’ rape claims for political gain.

Shadow attorney-general Michaelia Cash accused Labor of “weaponising” the rape allegations and said Senator Gallagher’s latest description of events was “very flimsy”.

On Saturday, Senator Gallagher denied misleading parliament over the Higgins case in 2019 and said that during the parliamentary hearing in question she was responding to a suggestion Labor had known about the incident for weeks and was trying to weaponise it.

Senator Cash told Sky News it was “very very clear” that Senator Gallagher had knowledge about the issue before it broke in the media. 

“What you have now, more and more coming out every single day, is that there appears to have been collusion with senior members of the Labor Party with the media,” Senator Cash said.

“This is what happens when you weaponise a rape allegation, there are consequences for that.”

Ms Higgins alleged she was raped by fellow Liberal staffer Bruce Lehrmann in 2019 inside the office of then-coalition minister Linda Reynolds.

Mr Lehrmann has always denied Ms Higgins’ allegation.

Last week, text messages between Ms Higgins and her partner David Sharaz emerged that suggest the pair considered strategising her story with Senator Gallagher, who was at that point in opposition, after the rape allegation was made public.

The opposition has since accused Senator Gallagher of misleading parliament in 2021 when she brushed off claims she was tipped off about the rape allegation before it was made public.

Aged Care minister Anika Wells defended her colleague’s explanation of what happened in Senate estimates back in 2021.

“(Senator Gallagher) said yesterday that she was aware of some things and she didn’t act on it,” Ms Wells told ABC News.

“She didn’t do anything with that information.”

The minister said the political conjecture from the opposition was “pretty horrifying” and “failing to see a really awful forest for the trees”.

Ms Higgins reached a compensation agreement with the Commonwealth in December 2022 after she launched legal action against her employers in the previous coalition government.

By Poppy Johnston in Canberra