Scott Morrison may be among several senior Coalition figures to face a grilling at the looming royal commission into the controversial robodebt scheme.

Prime Minister Anthony Albanese unveiled the terms of the royal commission on Thursday.

“It is vital so that we get to the bottom of how robodebt came about so that we can ensure that it can never ever happen again,” he said in Sydney.

“We know that almost 400,000 Australians fell victim to this cruel system. A human tragedy with very real consequences for its victims.”

Former Queensland Supreme Court Justice Catherine Holmes will lead the commission. Her final report is due by by April 2023.

The inquiry was an election commitment from Labor, and is expected to cost $30 million.

The robodebt program used an algorithm to work out whether Centrelink recipients had been overpaid. It was ruled unlawful in 2019, after claiming almost $2 billion in payments from 433,000 people.

The scheme was found in a class action lawsuit to have wrongly recovered more than $750 million from 381,000 people.

But the Morrison government has never detailed who was accountable for the scheme and which ministers knew of its problems.

Mr Morrison was Social Services Minister shortly before the automated scheme was introduced in 2016.

Other senior Liberal ministers, including Alan Tudge, Stuart Robert and Christian Porter, also had some oversight of the scheme at different times. However, the Morrison government never detailed who was accountable for the scheme and which ministers knew of its problems.

Mr Albanese dismissed criticism the commission would be an opportunity to attack the former government, saying there was a human cost to the scheme.

“People lost their lives. Every single one of my local constituents, and every member of parliament can tell stories like this,” he said.

“Those people who were most vulnerable were the least likely to go to their local member, to have the confidence to do that. And that’s why we need to get to the heart of why this occurred.”

The royal commission will look at the establishment, design and implementation of the scheme, who was responsible for it, why they considered robodebt necessary, and any concerns raised regarding the legality and fairness.

As well, it will examine the handling of concerns raised about the scheme, including adverse decisions made by the Administrative Appeals Tribunal.

The terms of reference will cover the outcomes of the scheme, including the harm to vulnerable individuals and the total financial cost to government, as well as measures needed to prevent similar failures.

Opposition Leader Peter Dutton said the royal commission was nothing more than a witch hunt.

“[The prime minister] should be concentrating more on how he can help families and less on how we can get square with Scott Morrison,” he said in Adelaide on Thursday.

“It’s clear that this is nothing more than a political witch hunt. And Anthony Albanese is spending more time looking in the rear-vision mirror than he is looking ahead.”

Mr Albanese said he did not want to pre-empt the commission when asked whether former Coalition ministers, including Mr Morrison, might be required to give evidence.

Mr Dutton said Government Services Minister Bill Shorten set up the parameters of the robodebt scheme when Labor was last in government.

“Bill Shorten should be the first witness at the inquiry because he set robodebt up,” he said.

Mr Shorten said while the class action lawsuit delivered justice for victims, more was needed to be done.

“This royal commission has to fill a gap,” he said.

“We still don’t know who conceived of this. The Federal Court judge, Justice Murphy, said that the senior public servants and responsible ministers should have known, but didn’t know.”

Australian Council of Social Service acting chief executive Edwina MacDonald welcomed the royal commission and said it would be a way to hold people to account.

“This royal commission is for the victims, and we welcome that there will be support for people who share their story,” she said.

-with AAP