Why a voice to parliament won’t impact First Nations sovereignty as Lidia Thorpe fears

The Greens senator Lidia Thorpe has vowed not to support the Indigenous voice to parliament unless she is “satisfied that First Nations sovereignty is not ceded”.

The Albanese government and constitutional experts reject the suggestion that entrenching the voice in the constitution would have any impact on sovereignty.

We spoke to experts who explained why the two questions are entirely separate.

What is sovereignty?

Sovereignty is supreme power or authority over a body politic.

Related: Senior Australian of the year Tom Calma ‘disappointed’ Lidia Thorpe may oppose voice

The constitutional law expert and deputy vice chancellor of University of New South Wales, George Williams, noted that “people speak about sovereignty in different ways – for many it’s as much a moral or political concept as it is legal”.

Who has sovereignty in Australia?

The crown, the commonwealth of Australia, the states and territories.

According to legal advice by the barrister Bret Walker in 2011, cited by the joint select committee on constitutional recognition of Aboriginal and Torres Strait Islander Peoples, “the basis of settlement of Australia is and always has been, ultimately, the exertion of force by and on behalf of the British arrivals”.

The colonies federated in 1901, and in 1967 a referendum gave the commonwealth authority over Aboriginal and Torres Strait Islander people but, since no treaty was made with Indigenous people, sovereignty was never ceded.

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Williams said Mabo and other high court cases establish that “at colonisation a new legal system arrived and that displaced the prior Indigenous legal systems”.

“Indigenous people still argue, and they can argue, that they never ceded their sovereignty – and that’s all true,” he said.

“And they can make those political, rhetorical or moral claims but the high court hasn’t recognised them.”

What does the Uluru statement say?

The Uluru statement from the heart contains an assertion of Aboriginal and Torres Strait Islanders’ sovereignty.

It says: “Our Aboriginal and Torres Strait Islander tribes were the first sovereign Nations of the Australian continent and its adjacent islands, and possessed it under our own laws and customs …

“This sovereignty is a spiritual notion: the ancestral tie between the land, or ‘mother nature’, and the Aboriginal and Torres Strait Islander peoples who were born therefrom, remain attached thereto, and must one day return thither to be united with our ancestors. This link is the basis of the ownership of the soil, or better, of sovereignty. It has never been ceded or extinguished, and co-exists with the sovereignty of the Crown.”

What is Thorpe’s concern?

In her statement on Wednesday Thorpe said Labor “needs to be prepared to be clear about our sovereignty”.

“It would take a lot for me to change my personal and long-held view that I don’t think First Nations justice will come from being written into the colonisers’ constitution. Labor has asserted through our negotiations that sovereignty isn’t impacted. It’s not enough. It needs to be explicit,” she said.

What has the government said?

When Thorpe asked Labor’s Murray Watt at Senate estimates in November whether “going into the Australian constitution through the voice [will] cede the sovereignty of First Nations people in this country”, Watt replied: “The answer is no.”

Officials from the Attorney General’s Department said they had not sought advice directly on point – but the question had already been answered by earlier processes.

What do the experts say?

In 2011 Walker gave advice referred to in both the 2012 Indigenous recognition expert panel report and the 2015 joint select committee report.

The expert panel summarised the advice as concluding: “That recognition of Aboriginal and Torres Strait Islander peoples in the Constitution as equal citizens could not foreclose on the question of how Australia was settled. Nor should constitutional recognition in general have any detrimental effect, beyond what may already have been suffered, on future projects aimed at a greater place for customary law in the governance of Australia.”

The 2015 report quotes the advice in full: “[British arrivals] did not ask permission to settle. No-one consented, no-one ceded. Sovereignty was not passed from the aboriginal peoples to the settlers by any actions of legal significance voluntarily taken by or on behalf of the former or any of them …

“The sovereignty [of the commonwealth] … thus does not depend in any way on any act of original or confirmatory acquiescence by or on behalf of Australia’s indigenous peoples.”

Related: What is the Indigenous voice to parliament and how would it work?

Williams said the voice referendum “would say nothing about sovereignty, and have no impact on sovereignty”.

“They’re like ships passing in the night.”

The academic Dr Hannah McGlade, a member of the UN Permanent Forum for Indigenous Issues, has written that “nowhere does the voice to parliament proposal suggest any agreement of Aboriginal people to cede sovereignty”.

“To the contrary, the proposal recognises the right of Indigenous people to be heard on laws affecting our people.”

Indigenous people’s sovereignty “can only be ceded under international law through the consent or agreement of Indigenous peoples”, she wrote in the National Indigenous Times.

“The Voice cannot be construed as cession of Aboriginal sovereignty by way of participation in the Commonwealth parliament and Australian body politic any more than the participation of Aboriginal politicians on behalf of their political parties.”

Are there risks in linking the two?

The 2012 expert panel said that “constitutional recognition of the sovereign status of Aboriginal and Torres Strait Islander peoples would be highly contested by many Australians, and likely to jeopardise broad public support for the panel’s recommendations”.

Williams said that including constitutional recognition of Indigenous sovereignty “would make the referendum unwinnable” and was better pursued through the separate treaty-making process.

“It could harm the treaty agenda … If you put sovereignty in with voice and people vote no, you’re in difficulties asserting [sovereignty], because it’s just been rejected. It would be counterproductive.”