Western Australia will have a new Minister for Corrective Services after Bill Johnston was removed from the portfolio.

Incoming Premier Roger Cook announced the new-look cabinet on Wednesday, which will see Paul Papalia, currently minister for Police, Defence Industry, and Veterans Issues, take on WA's troubled prison system.

The changes will be made official at a swearing in ceremony Thursday.

The state's only youth detention facility, Banksia Hill, in which Indigenous children are drastically overrepresented, has been in a prolonged crisis.

Kurin Minang human rights expert, law academic and member of the United Nations Permanent Forum on Indigenous Issues, Dr Hannah McGlade, welcomed the change in minister.

"I can say this was absolutely necessary as there has been significant mismanagement to the detriment of vulnerable children," she told National Indigenous Times.

"Bill Johnson did not appreciate the importance of Aboriginal leadership in relation to Banksia Hill, and it's critical that the new minister works with us to address this crisis.

"We have advised Tim Marney that Aboriginal Elders and cultural mentors are essential."

Megan Krakouer from the National Suicide Prevention and Trauma Recovery Project, which collected testimonies from hundreds of former Banksia Hill detainees for a class action, told National Indigenous Times Mr Papalia has "a unique opportunity to stand up for First Nations people as the Minister for Police and Minister for Corrective Services".

"But so far as Police Minister he has not stood up for First Nations people, not once," she said.

"Paul was the shadow minister for Corrective Services for nearly a decade and was relatively meek. He was quiet all the while as Johnston and McGowan demonised and abandoned marginalised children.

"Roger Cook should have shed a couple of his other portfolios and taken it on himself. Lead as someone who has sold himself as a social justice champion."

Ms Krakouer urged the new minister to speak with her and National Suicide Prevention and Trauma Recovery Project colleague Gerry Georgatos, who she described as "the best reformer in the country, the restorative expert".

"(Gerry Georgatos) was mostly responsible for halving the female detainee population in eight weeks in Banksia in 2020. He has mentored many of the boys considered as notorious by police and most have not reoffended, that says it all," she said.

"Call Gerry today, just as he was called in to Banksia on the first day of the state COVID quarantine in March 2020 when Banksia staffing levels were reduced to their lowest numbers ever. We delivered calm at Banksia and some changed lives."

Banksia Hill has been criticised by a range of law and human rights experts, including current and former Inspectors of Custodial Services, current and former Children's Court presidents, the prison staff union, and many others.

A new, separate class action has begun pertaining to Unit 18.

Last month a major riot, the latest in a string of incidents, rocked the facility, and letters from the Aboriginal Legal Service of WA detailing shocking allegations of abuse at Banksia Hill were tabled in Parliament by Greens MP Brad Pettitt.