The Morrison government would be forced to publish details of secret debt waivers, under a bill introduced by Labor senator Katy Gallagher on Monday.
Under the Public Governance, Performance and Accountability Act 2013, Finance Minister Mathias Cormann has the power to extinguish debts owed to the Commonwealth in cases where repaying the money would cause severe financial hardship.
This includes debts owed to the Australian Tax Office or Centrelink.
The Finance Minister can also make act of grace - or ex gratia - payments, in cases where the actions of a Commonwealth department or entity caused an unintended and inequitable result for someone.
However, the details of payments are not routinely published.
"The public should know how many debt waivers are being ticked off by the minister and how much those waivers are worth to the taxpayer," Senator Gallagher said.
"Other jurisdictions such as the ACT and Western Australia already publicly report details of these debts in some form. There is no reason why the federal government shouldn't do the same."
This bill would require the Department of Finance to publish the number of debts waived in its annual report, as well as the total dollar amount waived.
The department would also have to publish details of act of grace payments.
This could include details of future robodebt waivers, The Canberra Times understands. The government last week admitted its income averaging process was unlawful, which could open the way to more money being returned.
Senator Cormann's office said the bill would be carefully considered, however act of grace and debt waiver matters generally involved personal or private information, which is provided by applicants in confidence.
This meant any changes would have to be weighed against privacy laws.
The ACT government has been lobbying the federal government to wipe its $115 million housing debt, after the Commonwealth agreed to waive Tasmania's $157 million bill in exchange for Senator Jacqui Lambie's support on its income tax cut package.
The ACT will receive $27 million from the Commonwealth under the National Housing and Homelessness Agreement in 2019-20 but will have to give about half the money back to pay off the debt.