Independent inspections at youth prisons or immigration detention centres will be permitted after the Turnbull government pledged to ratify a United Nations treaty in a bid to stamp out torture.
The decision comes just two years after then prime minister Tony Abbott complained "Australians are sick of being lectured to by the United Nations" when the government was found in breach of an anti-torture convention.
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Don Dale inmate recounts harrowing conditions
Dylan Voller appears at the Royal Commission into the Protection and Detention of Children in the Northern Territory to give evidence of his treatment in detention. Vision courtesy ABC News 24.
The treaty - which Attorney-General George Brandis said should be ratified by December - will allow "unrestricted access" for international UN inspectors to enter any prison or place in Australia "where people are deprived of their liberty".
The move quickly kicked off legal debate over whether this will extend to Australia's offshore detention camps in the Pacific.
![A teenage Dylan Voller has a hood placed over his head and is strapped to a chair at the Don Dale Detention Centre in the NT.](/web/20170209075206im_/http://www.watoday.com.au/content/dam/images/g/q/d/v/t/f/image.related.articleLeadwide.620x349.gu996s.png/1486617324478.jpg)
The treaty also calls for local inspectors in Australia to be granted powers for sweeping independent assessments of prisons, police cells and immigration facilities.
The treaty was actually signed in 2009 - "that was three prime ministers ago," Senator Brandis told a human rights forum in Canberra on Thursday - but has languished in the years since without being implemented.
The decision to ratify comes at a sensitive time after revelations of abuse last year at the Don Dale youth detention centre in Darwin led to the establishment of a royal commission.
It also follows recent strife in Victoria's juvenile prisons and persistent reports of cruel treatment of people held in offshore immigration detention camps.
![Attorney-General George Brandis said Australia is committed to preventing torture and other mistreatment in places of ...](/web/20170209075206im_/http://www.watoday.com.au/content/dam/images/g/t/9/4/h/e/image.related.articleLeadwide.620x349.gu996s.png/1486617324478.jpg)
Australia is also bidding for a three-year seat on the UN Human Rights Council in an election to be held later this year.
Human rights lawyers hailed the move as a "critical step" and declared that if properly implemented, the treaty should lead to greater oversight of conditions at the Australian-run detention centres on Nauru and Manus Island.
![The decision has sparked debate about whether inspections will extend to places like the Manus Island asylum seeker camp.](/web/20170209075206im_/http://www.watoday.com.au/content/dam/images/g/t/4/y/e/1/image.related.articleLeadwide.620x349.gu996s.png/1486617324478.jpg)
"Under international human rights law, governments are responsible for what they do, regardless of where they do it," said Hugh de Kretser from the Human Rights Law Centre.
Senator Brandis said the Nauru and Manus Island facilities are operated by the respective governments.
"On the face of it, it will only apply to Australian detention centres - including Christmas Island, of course," barrister Julian Burnside told Fairfax Media.
"But if an international body wanted to assert that Australia runs the detention centres in Nauru and Manus, then the obligations would run to those places."
"But we know how Abbott responded the last time a [UN] special rapporteur said we were in breach of our obligations under the Convention against Torture."
Elaine Pearson from Human Rights Watch Australia said obligations should apply to both onshore and offshore facilities.
"Though the cynic in me says they will hide behind the argument that people are no longer 'detained' on Manus and Nauru due to slightly freer conditions of movement and also continue to hide behind sovereignty of Papua New Guinea and Nauru," Ms Pearson said.
The treaty - known as the "Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment", or OPCAT - is aimed at creating greater oversight for detention facilities across the globe.
Ben Saul, a professor of international law at the University of Sydney, said the new measures would make oversight of Australian detention more systematic and regular.
But he said it would be meaningless if the government did not act on the recommendations of inspections.
"This government has flatly rejected hundreds of previous UN findings about mistreatment in detention. It would be a miracle if the leopard changed its spots," Professor Saul said.
The UN human rights chief last year declared he was shocked by the abuse at Don Dale and called for compensation.
Senator Brandis said ratifying the treaty would not mean taking away authority or responsibilities from states or territories.
"This will be an important reaffirmation of Australia's deep commitment to preventing torture and other mistreatment in our places of detention," he said.