Labor MP Linda Burney has asked the Australian Federal Police to determine whether Human Services Minister Alan Tudge broke the law by disclosing a welfare recipient's personal information to a journalist.
Public servants have told a Senate Estimates hearing in Canberra the "protected" information was collated by DHS officials and approved for release by Mr Tudge's office.
The department sought legal advice before releasing the information but did not obtain a public interest certificate, with officials claiming they did not need to.
Mr Tudge and his department claimed the disclosure was legal according to section 202 of the Social Security Act 1999 and section 162 of the A New Tax System Family Administration Act 1999.
Lawyers believe this legal argument is untested and could become a test for privacy law.
In a statement, Mr Tudge said the Government took privacy "very seriously" and said information was released to the journalist after approval from the department's chief legal counsel.
"Where a person makes a false public statement about their dealings with the Department of Human Services, whether through the media or otherwise, social security law and family assistance law enables the department to disclose customer information to the extent that it is necessary to correct factual inaccuracies or potentially misleading information," he said.
It is common for politicians to refer matters to the federal police and doing so does not automatically trigger and investigation.
In her letter to AFP commissioner Andrew Colvin, Ms Burney said legal experts claimed a reliance on section 202 was "not available" and contrary to "a proper reading of the ACT and decades of established department practice".
"An AFP spokesman confirmed the receipt of the letter and said it would be evaluated in accordance with normal procedures," he said.