Prime Minister Anthony Albanese did not receive legal advice from the attorney-general's department before unveiling a draft referendum question for an Indigenous voice to parliament.
Government officials confirmed the lack of advice at Senate estimates on Monday, drawing scathing criticism from Liberal senator Paul Scarr who described himself as "staggered" and "gobsmacked".
But minister Murray Watt was quick to defend the prime minister's action, saying the statement he made in July was only intended as a draft and required further consultation.
Mr Albanese revealed the draft question at the Garma Festival: "Do you support an alteration to the constitution that establishes an Aboriginal and Torres Strait Islander voice?"
Senator Watt said there was no suggestion it was the exact question Australians would be asked to answer at the ballot box.
"These are proposed words that have been put forward by the prime minister, they are not necessarily the finished product," he said.
"When he made the announcement, he referred to them as a starting point and we welcome discussion from all members of the public."
Senator Scarr said he found the lack of legal consultation "extraordinary".
"I would expect ... given the significance of the prime minister tabling an amendment to our constitution would actually seek advice from the attorney-general's department with respect to the wording," he said.
"I'm absolutely staggered, I'm gobsmacked to be frank."
Constitutional law office general counsel David Lewis agreed with the minister the statement was for draft purposes and didn't necessarily need legal advice.
"Those words were very similar to some words that have been ... developed by a number of groups and publicly available for a number of years," he said.
"When the prime minister announced those words, he said this is a draft for discussion ... I expect there'll be further discussion before the draft is finalised."
Earlier, Indigenous Australians Minister Linda Burney addressed leader Noel Pearson's statement First Nations people were "much unloved" and a referendum may fail due to "prejudice, contempt and violence of the past".
"He is right in the sense that with the equal marriage plebiscite, a lot of people knew people that would be directly affected by this ... I don't think that's the case so much with Aboriginal people," Ms Burney told the ABC.
"But the great thing is Noel also described the voice as a bridge to unite, at long last, First Peoples and the rest of the country and that to me is where we should focus."
