Christian Porter says governor general’s power to dismiss prime minister keeps ‘governments on their toes’

Australia’s attorney general Christian Porter has declared the governor general having reserve powers “keeps executive governments on their toes” and he says the palace letters don’t tell us “anything about the role of the governor general that we didn’t really already know”.

Porter, who on Wednesday characterised himself as a “sort of a constitutional conservative”, said Australia was probably the best-functioning democracy in the world, “and if you don’t like this system, it’s incumbent [on you] to suggest the next one”.

“I think that many people who argue that [the dismissal of the Labor prime minister Gough Whitlam in] 1975 … should be an event that pushes us towards a republic don’t like the fact that there’s any degree of unclarity or uncertainty in the system,” Porter told 6PR in Perth. “But I wouldn’t conceive of this as being unclear or uncertain.

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“We know what the governor general can do, we’ve seen it done and it’s that power that keeps executive governments on their toes,” he said. “That is part of the separation of powers, part of the balance of powers that good functioning democracies have got, and we’re probably the best-functioning democracy in the world.”

Porter was responding to the release of a trove of letters between the Queen, her representatives and then governor general John Kerr in the lead-up to Whitlam’s dismissal after a four-year court battle launched by the historian Jenny Hocking to gain access to primary source material about the events of 1975 and the aftermath.

Porter joined the high court action against Hocking with the National Archives of Australia, an action they ultimately lost.

The correspondence confirms the extent to which the palace was drawn into Kerr’s plans in 1975 to remove the Labor leader from office. The correspondence – which proves the governor general of Australia flagged a “last resort” option to dismiss Whitlam with the Queen’s private secretary, Martin Charteris, and Charteris supported Kerr in his view that he could use his reserve powers – has renewed the debate over whether Australia should become a republic.

Hocking is continuing to examine the letters, but has pointed to a handwritten note added as a postscript to a letter from Charteris to Kerr, dated 24 September 1975. Charteris wrote to Kerr about the political crisis gripping the Whitlam government, saying “the governor general of Australia does not seem to lie on a bed of roses”.

“It is clear that you may be faced with some difficult constitutional decisions during the next month or so,” Charteris wrote. He added a handwritten note at the bottom of his letter, pointing out a book that postulates a governor general can dissolve parliament when supply is blocked.

Related: The palace letters amount to an act of interference in Australian democracy | Katharine Murphy

“I suppose you know Eugene Forsey’s book The Prerogative of the Dissolution?” he says. Charteris says Forsey’s book articulates the idea that “if supply is refused this always makes it constitutionally proper to grant a dissolution”.

As well as revealing the exhaustive conversations between Charteris and Kerr during the lead-up to the dismissal, the letters suggest the palace was nervous about the prospect of Kerr writing about the events of 1975. In January 1977, Kerr wrote to Charteris advising him that he’d been writing and had received “offers from publishing companies to publish my ‘memoirs’ or ‘autobiography’”.

He said he was aware he couldn’t write about his time as governor general but may be able to write about his earlier life. “I shall not make any decision about any of this until I have a chance to speak to you when you are in Australia,” Kerr wrote.

The reply from the palace left little room for ambiguity about its view of Kerr recounting of events from his time in office. “We will discuss the matter further when we meet in Australia. In the meanwhile I think all that I can usefully say is the obvious: that it would be clearly improper for you to publish anything about events which have taken place during your term of office whilst you remain governor general,” he said.

Charteris also warned there could be unforeseen consequences if Kerr was to write about his earlier years. “I cannot, personally see anything wrong in your publishing autobiographical material from a period before you assumed office, but I think one must recognize that almost anything you publish now will be scrutinised with November 1975 [the dismissal] in mind, if only to discover and discuss how your past life may have influenced your later actions.”

Related: John Kerr complained to Buckingham Palace of Gough Whitlam's 'malice' after dismissal

“I can visualize commentators avidly going back to your childhood and school days for ‘leads’!”

The attorney general said on Wednesday he was yet to read all the documents, but he said the letters did not support “a theory that somehow the Queen and the palace “gave a royal green light” to the use of the reserve powers. “I certainly don’t think that they show that.”

He said advocates for a republic in Australia had “tried fruitlessly to argue for a better system than the one we’ve got for 40-plus years without much success, so whether or not they want to be devoting their energies to that or more important matters is a matter for them”.

“I think our system works remarkably well, probably the best working system in the world,” Porter said. “The idea that when we’ve got actual problems around employment, around dealing with the health crisis that we’re in, ensuring that our economy can grow its way out of the most tumultuous period in at least 100 years – the idea that we would even entertain spending oxygen on a debate about a republic, to me, seems bizarre.”