Senior government officials will be called before a royal commission to give evidence explaining their roles in the robodebt scandal.
The commissioner, Catherine Holmes, said on Tuesday that although much was now known about how the failed scheme operated, little had been revealed about the government’s response “behind the scenes” to warnings and criticism.
The Coalition started the robodebt scheme in 2015 and it ran until November 2019 when the government accepted the method used for raising Centrelink debts was unlawful.
That concession followed sustained criticism from activists, social services groups and opposition parties in parliament.
The saga concluded with a $1.8bn federal court settlement between the government and a class action with 453,000 victims.
“Many people at different levels of government will be asked to give an account of their role in the devising, implementation and continuing of the robodebt scheme,” Holmes said in her opening address.
“But the focus, appropriately and in accordance with the terms of reference, will be on those in senior positions who had or should have had oversight.”
The former prime minister Scott Morrison, current opposition frontbenchers Alan Tudge and Stuart Robert, and former ministers Christian Porter and Michael Keenan, all held portfolios with oversight for the scheme.
Holmes said the robodebt program was based on an “unsound” premise and used an “automated” debt recovery process on a “scale not previously attempted”.
It used a longstanding method to check whether people had correctly reported their fortnightly income to Centrelink using annual ATO data.
But, crucially, Centrelink issued automated debts without compliance officers gathering further evidence, as occurred before robodebt.
“The premise for the scheme was unsound because it treated average earnings as though they were actual earnings,” Holmes said.
The senior counsel, Justin Greggery KC, said the “first form of the robodebt scheme” had been outlined in an executive minute to the then social services minister in 2015. The minister at the time was Morrison.
The minute has not been released publicly despite requests from the Senate and via the freedom of information process.
Greggery said the administrative appeals tribunal first ruled in March 2017 that the method used to raise debts in the robodebt program was invalid.
He said the inquiry expected to receive evidence that in the months to May 2017, more than 20 similar decisions were handed down by the AAT.
The first finding “ought to have been of significance to the departments of social services and human services”, Greggery said.
Instead, the scheme continued with only minor changes until November 2019.
“In the face of public questions about the process, ministers and those in senior roles in the Australian public service asserted that the system worked well,” Greggery said.
The inquiry will sit in Brisbane and some witnesses will give evidence via video link, though it was unlikely “positions of seniority will be permitted to give evidence remotely”.
Holmes said she understood some victims would not want to “revisit” their stressful experiences of the scheme, but she encouraged those affected to make a submission.
The government services minister, Bill Shorten, said it was hoped the inquiry would “get to the bottom of why this happened and make sure it can never happen again”.
He made the comments alongside Jennifer Miller and Kath Madgwick, whose sons separately took their own lives while being pursued over Centrelink debts.
The inquiry will meet again on 31 October.
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