A royal commission into child abuse in Northern Territory detention centres would be a waste of time without the backing of indigenous people, a former Liberal senator says.
Two co-commissioners will head the probe after former NT chief justice Brian Ross Martin quit the role on Monday.
Mick Gooda - the Aboriginal and Torres Strait Island Social Justice Commissioner at the Human Rights Commission - has taken his place alongside former Queensland Supreme Court Justice Margaret White.
Former Liberal Senator Fred Chaney said it was sensible of Justice Martin to step down after it emerged his daughter worked for the NT attorney-general's office between 2009 and 2011, a period covered by the royal commission.
"I think that shows admirable good sense on his part," Mr Chaney told AAP.
"To have a royal commission that from the outset the Aboriginal community didn't have confidence in would be a waste of time."
The Royal Commission was announced last week after footage emerged of boys being stripped naked, tear-gassed and held in solitary confinement at Darwin's Don Dale detention centre.
The National Congress of Australia's First Peoples said Mr Gooda and Justice White should have been in charge from the start.
"Mick's been working in this field for many, many years, decades in fact, and he's been speaking out strongly about law and justice issues in our country," co-chair Jackie Huggins said.
Northern Australian Aboriginal Justice Agency chief executive Priscilla Collins said "we didn't have anything personally against Brian Martin, it was the process".
A spokesman for NT Chief Minister Adam Giles, who did not speak with media directly as he was at the races, said he was confident the co-commissioners would conduct the inquiry fairly and rigorously.
The Law Council of Australia welcomed the new royal commission heads but called on the government to examine youth detention practices across the country.
