Former prime minister Malcolm Turnbull will give evidence on what he knew about the unlawful robodebt scheme while he was in office, when the royal commission into the program resumes.
Mr Turnbull, who was prime minister during the height of the debt recovery scheme, will be the commission's first witness during its final week of hearings.
The robodebt scheme used income averaging from tax office data to calculate debts and ran from 2015 to 2019, when it was ruled as unlawful.
The commission is examining how the scheme was allowed to continue, given significant concerns had been raised about its legality by early 2017.
The government unlawfully recovered more than $750 million from more than 380,000 people through robodebt with the debt notices being blamed for contributing to multiple suicides.
Concerns about robodebt potentially being unlawful emerged in early 2017 when Mr Turnbull was prime minister.
The royal commission previously heard Mr Turnbull had raised issues with the scheme with former human services minister Alan Tudge, who told the minister he was unhappy about it.
It also emerged the prime minister sent Mr Tudge a newspaper article which stated the robodebt scheme could be illegal.
Other witnesses set to take the stand at the commission on Monday include former Department of Human Services director Kristen Foster and Services Australia general manager Jason McNamara.
The commission will conclude its hearings on Friday, with the final report due to be handed down on June 30.
The deadline for the report was extended after an extra 100,000 documents were produced.
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