Tony Abbott’s chief of staff has been called many things during a backroom political career spanning 15 years – “the queen of no”, “the chief” and “the most powerful woman in politics”.

But Peta Credlin is now facing calls to go.

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On Friday, Fairfax Media reported an unnamed “key backer” of the Prime Minister had demanded Ms Credlin be sacked to appease the backbench.

“Peta Credlin has become a lightning rod for a lot of dissatisfaction within the Government,” Fairfax Media chief political correspondent Mark Kenny said.

“That’s both in the ministry and across the backbench.”

According to backbench sources who have spoken to 7.30, much of the criticism of Ms Credlin stems from the control she wields over everything from staff appointments to what is discussed in Cabinet.

“Some have even said you can’t send [the Prime Minister] a text message, because you’re not sure if he’s going to be the one who’ll receive that text message … there’s a real sense that Ms Credlin is omnipresent and very powerful in Tony’s ear,” Mr Kenny said.

Peta Credlin has been Tony Abbott’s chief of staff for five years.

She is widely viewed as having brought the discipline to his office that made him such a successful opposition leader and won him the election.

David Epstein, who was Kevin Rudd’s chief of staff during his first prime ministership, said tight control from the Prime Minister’s office was essential, particularly during the transition from opposition to government.

“Governments can get off to very bad starts if they don’t apply discipline from the centre,” he said.

But Professor Anne Tiernan of the School of Government and International Relations at Griffith University said control eventually needed to be released.

“People will tolerate discipline and control at the beginning, but once ministers are in Cabinet, once they are elected, they don’t want unelected people to think they’re running the show. A subtle change of style is necessary,” she said.

“The average tenure in the role tends to be less than two years … it’s exhausting, but also the needs change, the situation changes and your ability to be effective might diminish as the ministers become more confident or become more assertive and want more autonomy.”

Credlin referred to as ‘the chief’ by PM

Ms Credlin has broached new ground for a chief of staff. Until this week, she regularly attended and played an active role in Cabinet meetings, Mr Kenny said.

“She’s been known to play a very pivotal role in determining what issues go before Cabinet. She’s extremely close to the Prime Minister – he often refers to her as ‘the chief’.”

“I’ve heard stories of MPs and ministers agreeing with Tony Abbott on something in a conversation, only to be told later by the Prime Minister that whatever has been agreed can’t be gone ahead with because the chief has said no.”

But the Assistant Treasurer, Josh Frydenberg, who was Tony Abbott’s parliamentary secretary until December’s Cabinet reshuffle, told 7.30 the Prime Minister was the only chief.

“At the end of the day she understands her place in the system, and that place is as a senior advisor, as a chief of staff. But ultimately it’s with the elected politicians that decisions are made,” he said.

Kay Patterson, the former Victorian senator who first employed Peta Credlin as a staffer in 1999 said the image of a bossy control-freak has been put about by people who resent her role as gatekeeper.

“It’s not the Peta Credlin that I know,” she said.

“[In her role] you have to say no to people and they don’t like it, and that’s a very difficult situation to be in.”

Ms Patterson did not share the view, aired by the Prime Minister in December last year, that criticism was being levelled at Ms Credlin because she is a woman.

“I’m not sure that the gender issue is a major issue,” she said.

“The major issue is she’s a great asset to the Coalition and if I were trying to undermine the Government, I’d attack the assets.”

But whether she is now more of a liability than an asset is unclear.

Since the Christmas break, Ms Credlin has certainly taken a lower profile.

She did not attend the two-day Cabinet meeting this week, nor was she seen at the Prime Minister’s official engagements at the Press Club and a childcare centre. Instead, he took his wife Margie.

On Thursday Mr Abbott assured reporters Ms Credlin was still his chief of staff.

But whether or not she weathers the coming days as Mr Abbott prepares for a potential spill motion against him on Tuesday, she remains a source of friction for some Coalition members.

“More than one of them have said … either she goes, or he will eventually go,” Mr Kenny said.

“It now looks more likely that he will eventually go whether she goes or not.”

– Madeliene Morris