THE Morrison government is about to establish a royal commission into violence and abuse of people with a disability.

The aim is to have the terms of reference finalised before the election. The disability area is a shared one, so the royal commission would be set up jointly with the states and territories.

As of late Wednesday, Queensland, Victoria, NSW, South Australia and Tasmania had agreed to the inquiry; Western Australia and the two territories are expected to do so soon.

Scott Morrison, campaigning in Tasmania, flagged a very extensive scope for the commission.

“I think it will be a royal commission of a similar size and standing as what we saw with institutional child sexual abuse. Let’s remember that went for four years. It had five commissioners,” he said.

There is no cost for the royal commission as yet and the federal government wants the other governments to contribute. The child sexual abuse commission cost about A$500 million; the banking inquiry was around $75 million; the aged care one is set to cost about $100 million.

The disability sector has been pressing for the inquiry. Greens senator Jordon Steele-John, who has a disability, has been one of the loudest voices. The opposition has promised a royal commission, and earlier this month parliament passed a motion calling for one. The Coalition opposed that motion in the Senate but voted for it in the lower house.

In a letter to state and territory leaders Morrison said the scope of the inquiry being proposed by disabled people and advocates “is broad, including mainstream services that are regulated by state and territory governments such as health, mental health and education services provided prior to the establishment of the NDIS.

“The cooperation and support of state and territory governments is therefore essential”.

Morrison said he was seeking views from the states and territories on the “most appropriate consultation pathways to progress” the commission, including through the Council of Australian Governments. This process should also consider cost sharing. “I am also seeking views on options to undertake meaningful consultation with the disability sector, to ensure that the perspectives of people with disability are incorporated and they are provided with appropriate support”.

The opposition accused Morrison of haggling with the states over the funding of the royal commission, saying that “Labor committed to a separate, dedicated and fully federally funded royal commission in May 2017”.

Michelle Grattan is a professorial fellow at the University of Canberra. This article was originally published on The Conversation.