ACT's ousted deputy leader Heather Roy is under pressure to quit Parliament and the party is checking out a replacement MP.
Mrs Roy is on leave considering her future after being dumped last week and is surrounded by a controversy over the leaking of explosive documents she had prepared to defend herself.
The notes accused party leader Rodney Hide of being a bully and accused him of working to undermine her in her previous role of Associate Defence Minister.
Her ministerial adviser, Simon Ewing-Jarvie, has admitted he leaked the notes to the media after losing his job when she resigned her portfolios.
Mrs Roy's relationship with Mr Ewing-Jarvie is also being questioned, and a Sunday newspaper reported she spent last Friday night at his home.
Mr Hide said today ACT was considering whether there was a way back for Mrs Roy, a list MP.
"The difficulty she's got is that she has put herself into a position where there are a lot of tough questions to be asked," he said.
"We're very supportive of Heather, but it's a hard time."
TV One News reported tonight the next candidate on ACT's list, Dunedin businesswoman Hilary Calvert, had come to Wellington to talk to party bosses.
"I have spoken with them to the extent of them having an understanding that if there is an opportunity, then I will step up," Ms Calvert said.
In Parliament today ACT MPs presented a united front, clustering together as they went into the debating chamber.
Mr Hide told reporters he had not been involved in the Security Intelligence Service's (SIS) decision to refuse security clearance for Mr Ewing-Jarvie - the latest twist in the story around the former army officer who appears to have been a close confidante of Mrs Roy.
Mr Hide said neither he nor Prime Minister John Key had anything to do with the SIS decision,
He again denied one of Mrs Roy's most serious allegations - that he took a confidential defence paper out of her office without her permission.
He said that when he asked to see the paper, which it was later confirmed he was entitled to read, she told him to look at it in her office.
He said he told her he was going to take it to his own office.
"She sort of sighed, and I picked up the paper and walked out," he said.
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