A former federal government minister and the head of the department involved in the robodebt debacle will front a royal commission into the unlawful scheme.
Former Liberal MP Michael Keenan, human services minister between 2017 and 2019, and former department secretary Renee Leon will give evidence on Tuesday.
Mr Keenan retired from parliament ahead of the 2019 federal election and Professor Leon was appointed vice-chancellor of Charles Sturt University in 2021.
Hundreds of thousands of Australians were sent debt notices under the robodebt scheme, which operated between 2015 and 2020 and unlawfully recovered more than $750 million.
The final week of hearings is focused on the fairness, legality and policy considerations of robodebt and how it was able to operate despite government departments knowing the debt calculation method was illegal.
On Monday, the commission heard a top public servant had questioned the legality of robodebt and thought the arguments supporting the income averaging scheme were weak.
Ex-human services department deputy general counsel of program advice and privacy Mark Gladman said he raised concerns about the scheme in 2017.
He urged the department to seek urgent legal advice from the Australian Government Solicitor.
Yet the department's former general counsel of commercial law Lisa Carmody said she did not recall Mr Gladman raising legal concerns.
The robodebt scheme operated for several years despite concerns it was unlawful, with some people taking their own lives while being pursued for debt.
The royal commission is set to hand down its report on June 30 after the deadline was extended when an extra 100,000 documents were produced.
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