The Northern Territory government has become the first jurisdiction in Australia to raise the minimum age of criminal responsibility from 10 to 12 years.
But it remains short of the United Nations recommended age of 14 years, with advocates saying they will work towards having the benchmark raised further.
The new laws passed by parliament overnight mean children aged 11 or younger who commit offences will no longer be charged by police or imprisoned.
They will instead be referred to family support and intervention programs and placed in temporary accommodation if their homes are deemed unsafe.
Attorney-General Chansey Paech said the NT is "taking a smarter approach to youth justice" and would break the cycle of reoffending.
"Our focus is on delivering proven solutions that will benefit all of our children, their families and the Territory as a whole," he said on Wednesday.
The NT government also stressed that police would continue to investigate offences after the amendments came into effect in late 2023.
Victims of crime would continue to receive assistance through financial compensation and support, it said.
The North Australian Aboriginal Justice Agency welcomed the "momentous" changes, saying the NT's tough-on-crime approach over the past two decades had failed vulnerable children.
The agency said locking up children increased the risk of reoffending with more severe behaviour likely when they did.
The majority of children aged 10 and 11 who had been incarcerated on remand did not receive a custodial sentence for their offences but were subject to the "trauma we know the loss of liberty inflicts on the human psyche", the agency said.
The Office of the Children's Commissioner NT also commended the amendment, saying it was a step in the right direction.
"A majority of the children finding themselves in detention have experienced trauma and grappled with living below the poverty line," Acting Commissioner Nicole Hucks said.
"More meaningful responses are needed to support children and their families to have their basic needs like housing and food security met."
The NT Council of Social Service also applauded the new laws.
"Children need to be supported to address their offending and referred to support services that provide the help they need and locking them up is not the solution," chief executive Deborah Di Natale said.
The agency, the commissioner's office and the council said the government should invest in more community leadership to address issues of youth offending.
They also called for the age of criminal responsibility to be raised to 14, in line with United Nations, international and medical expert standards.
The UN Committee on the Rights of the Child formally noted in 2019 its serious concern about the "very low age of criminal responsibility" in Australia.
Mr Paech said the changes were informed by recommendations from the Royal Commission into the Protection and Detention of Children in the NT.
Opposition Leader Lia Finocchiaro said the Labor Fyles government had wiped thousands of past crimes from the record and green-lit crime, no matter how serious, for children under 12.
"It's basically a free-for-all for young criminals. Labor has sent a dangerous message to them, telling them to go their hardest because there won't be any consequences," she said.
"It's also insulting to police to say they can still investigate crimes but cannot arrest or charge someone for those crimes."
The age of criminal responsibility is the age when a child is considered by law to have understood that their actions were wrong and can face criminal charges.
The legislation will be reviewed by government in two years.
Australian Associated Press
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