“Looking back on it,it kind of appears those talking points avoid that question as well,” he said.

A Federal Court judge found in 2019 that income averaging – the method used to calculate debts of thousands of vulnerable people – was unlawful,a conclusion that had already been reached in legal advice seen by both the departments of human services and social services several years before.

The scheme used Tax Office annual income data and averaged it over 26 fortnights,presuming income was the same across each,and put the onus on welfare recipients to prove they didn’t owe the government money.

Porter,who is being represented by high-profile silk Arthur Moses,SC,in the inquiry,was social services minister from September 2015 to December 2017,before being elevated to the role of Attorney-General.

He did not contest last year’s federal election following the fallout from a historical rape allegation he strenuously denies.

Earlier,former Coalition human services minister Alan Tudge told the commission he should have sought legal advice over the lawfulness and accuracy of income averaging.

The robo-debt royal commission heard that former prime minister Malcolm Turnbull texted Tudge aSydney Morning Herald article raising questions of the accuracy and legality of the welfare crackdown to Tudge in January 2017,when Tudge was human services minister.

Tudge said he later met with Turnbull but spoke mainly about problems with the implementation of the scheme.

The commission was also shown a document drafted by Tudge’s department to the Australian Government Solicitor about the lawfulness of income averaging around that time.

Tudge told the commission he couldn’t explain the document prepared by the department. “This is the first I’ve seen of this document,” he said.

Greggery asked:“Can you think of any reason why draft instructions to the Australian Government Solicitor on a program affecting so many Australians would not have been progressed to the final stage in seeking advice?”

Tudge answered:“No.”

Greggery:“You agree with the benefit of hindsight,it would’ve been prudent to seek legal advice on the question of accuracy and lawfulness?”

Tudge:“Definitely. Even going back to 1990[when the Coalition said income averaging had begun],and at every stage of the development of the process which used income averaging.”

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