Queen Elizabeth II's office assured her representative in Australia he had the power to bring down the Australian Government a week before he took the extraordinary move in 1975 and created a political crisis, according to letters released on Tuesday.
The National Archives of Australia released more than 1200 pages of letters and press clippings between the monarch's office and Governor-General Sir John Kerr from August 1974 to December 1977 after a court ruled in May that they could not be kept secret indefinitely.
Kerr dismissed Prime Minister Gough Whitlam's reforming centre-left Labor Party Government on November 11, 1975, to resolve a deadlock in Parliament on the authority of the Queen, who is Australia's head of state.
The Queen's private secretary Sir Martin Charteris wrote to Kerr on November 4, 1975, that the monarch's power to dissolve a parliament had not been used in years and some argued that the power no longer existed.
"I do not believe this to be true," Charteris wrote.
Charteris also wrote that if Kerr did "what the constitution dictates, you cannot possible (sic) do the monarchy any avoidable harm."
"The chances are you will do it good," Charteris said.
Kerr did not tell the Queen he had decided to remove Whitlam and replace him with Opposition leader Malcolm Fraser as caretaker Prime Minister until after he had done it.
"I was of the opinion that it was better for Her Majesty not to know in advance," Kerr wrote on November 11, immediately after taking the unprecedented step.
Charteris congratulated Kerr for not warning Whitman that he was considering bringing down his Government.
That could have put the Queen in an "impossible position" if Whitlam tried to get her to fire Kerr while Kerr was trying to fire Whitlam. Kerr died in 1991.
The only dismissal of an elected Australian Government on the authority of a British monarch triggered a political crisis that spurred many to call for Australia to sever its constitutional ties with Britain and create a republic with an Australian president. Suspicions of a US Central Intelligence Agency conspiracy persist.
The release of the letters is a victory for historian and Whitlam biographer Jenny Hocking who has been trying for years to get access to them.
Labor leader Anthony Albanese, Australia's Opposition leader, said the 1975 crisis reinforced the need for an Australian head of state instead of the British monarch.
"It is, I think, a blight on our character as a nation that a democratically elected Government was dismissed," Albanese said.
"The action of the Governor-General on November 11 to dismiss a Government, to put himself above the Australian people, is one that reinforces the need for us to have an Australian head of state, reinforces the need for us to stand on our own two feet," he added.