The majority of children locked up on any single night in Australia are Indigenous, new data shows.

A report released by the Australian Institute of Health and Welfare (AIHW) on Friday shows at the end of the June quarter this year, 845 youths were in custody, with 90 per cent of them being teenage boys.

Despite making up only 6.6 per cent of the population aged 10-17, 65 per cent of young people in detention were Indigenous.

The data revealed the rate of First Nations children aged between 10-17 in detention has increased, with Indigenous children now 27 times more likely than non-Indigenous children to be incarcerated.

Across the country, the rate and number of First Nations young people aged 10–17 in detention have been increasing since the September quarter 2020.

"First Nations people have a long history of over-representation in the youth and adult justice systems in Australia," the report read.

"This over-representation reflects a history of trauma, cultural dispossession, and forced displacement and assimilation that have affected them, their parents, families and communities."

On an average night in the June quarter, there were 509 First nations young people aged 10 and over in detention.

The data comes only a day after Queensland officially passed a bill which experts argue will only exacerbate children being placed in custody, with the state suspending the Human Rights Act for the third time in less than two years.

Juveniles charged with several serious crimes, including murder, manslaughter, and burglary, will face tougher maximum sentences, whilst the bill also removes "detention as a last resort"—a tenet of the 1991 Royal Commission into Aboriginal deaths in custody and several international commitments Australia has ratified.

The Queensland government was described by First Nations Justice Director at the Human Rights Law Centre, Maggie Munn, as having "blatantly disregarded international law about the treatment of children in the criminal legal system".

The Northern Territory has also recently lowered the age of criminal responsibility to 10, under the guise of community safety, despite an outcry from medical and legal experts.

Tellingly, the AIHW report shows both the Northern Territory and Queensland had the highest rates of First Nations young people aged 10–17 in detention, at 46 and 42 per 10,000 children and young people respectively.

The rate of First Nations young people aged 10–17 in detention on an average night also increased in the Northern Territory (from 14 to 46 per 10,000), Queensland (from 29 to 42 per 10,000) and New South Wales (11 to 21 per 10,000).

It fell in both Western Australia (from 36 to 25 per 10,000) and Victoria (from 9.9 to 5.8 per 10,000).