The secret ministry saga of the Morrison government could have been avoided if the head of state was accountable to the Australian people rather than to the crown, the republic minister says.
Federal parliament is debating new laws proposed by the Albanese government to stop secret appointments to ministries.
The laws were proposed after it emerged former prime minister Scott Morrison appointed himself minister of health, finance, industry, science, energy and resources, treasury and home affairs between 2020 and 2021.
He did so without the knowledge of most of his coalition colleagues or the public.
But Assistant Minister for the Republic Matt Thistlethwaite believes the saga could have been avoided had there been an Australian head of state, appointed by the Australian people.
"A head of state put into that situation - such as the one (Mr Morrison) left the governor-general with - would be obliged, in my view, to ensure that the Australian people were informed of the former prime minister being sworn into those ministries," he told parliament.
Mr Thistlethwaite said the governor-general is appointed as the King or Queen's representative and swears allegiance to the crown.
But he said a head of state appointed or elected by the Australian people would have an obligation to ensure the public knew who was administering government on their behalf, a fundamental principal of democracy.
"If (the prime minister) were to go to an Australian head of state and say to them, 'I want you to swear me into these ministries' of course, the head of state would be obliged to do so," Mr Thistlethwaite said.
"But if they were appointed by the Australian people, I believe they would also be obliged to say to the prime minister, 'if you don't tell the Australian people, then I will'."
When the secret ministries emerged, Governor-General David Hurley was criticised for not instructing Mr Morrison to make the appointments public.
But Mr Thistlethwaite said the governor-general was not to blame for the situation Mr Morrison put him in.
"Under our system, the Westminster system, the governor-general acts on the advice of the government of the day and that is what the governor-general did," he said.
The assistant minister said that after a referendum on the Indigenous voice to parliament, Australians would need to have a serious discussion about becoming a republic.
"Hopefully some good can come of this dark period in our history where the Australian people were none the wiser about who was administering government on (their) behalf," Mr Thistlethwaite said.