Raising the age of legal responsibility to 14 is a "common-sense" step for both children and the broader community, the Aboriginal Legal Service NSW/ACT says.

On Tuesday, the ACT will become the first Australian jurisdiction to raise the minimum age of criminal responsibility to 14, aligning with long-standing expert medical and legal recommendations.

The change includes carve-outs for 12- and 13-year-olds who commit serious and intentionally violent crimes. Still, advocates say the reform brings the justice system in line with modern understandings of child development.

ALS Chief Executive Karly Warner said the ACT's decision is "backed by the evidence about children's development and what works to keep communities safe".

"This reform will keep more children where they belong: in their homes, communities, schools, playgrounds and sports fields, supported to thrive rather than being dragged through court and languishing in youth prisons," she said.

As part of the ACT's early intervention model, children who are involved in — or at risk of — harmful behaviour will be referred to a Therapeutic Support Panel.

"Children and young people who are at risk of entering the youth justice system have often experienced complex trauma, family violence, and homelessness. Many also have mental health issues, live with disability, or use drugs and alcohol," said Michael Pettersson, the ACT's Minister for Children, Youth and Families.

He said the reforms are focused on "early intervention and co-ordinated, wrap-around services," so children get the help they need to lead "healthy and fulfilling lives".

"We know that early intervention is more likely to keep kids out of the justice system in the long term. And that leads to a safer and happier community for everyone," Mr Pettersson added.

Ms Warner emphasised the risks of early criminalisation, noting: "The younger a child is at first contact with the legal system, the more likely they are to keep coming back into contact with police and courts and to experience adult imprisonment.

"That's why raising the age of legal responsibility to 14 is a common-sense move not only for children, but for all members of our communities," she added.

Vanessa Turnbull-Roberts, the ACT's Aboriginal and Torres Strait Islander Children and Young People Commissioner, said it's crucial that responses are led by communities, not policing.

"Young people in the ACT are facing significant implications of being profiled, targeted and consistently subject to surveillance by policing," she said.

"We must safeguard all our children and young people and ensure that all our children and young people are supported with early intervention and prevention. This includes culturally safe programs that operate after hours."

Despite the new approach, the ACT Government said police will remain the first point of contact for the public, with officers deciding the most appropriate response for any child or young person involved.

The Territory's Attorney-General, Tara Cheyne, said the changes reflect a desire for a justice system that is "fair, evidence-based and puts the wellbeing of children at its core".

"It is not about removing accountability, but about responding in a way that leads to better outcomes for young people and the broader community," she said.

While praising the ACT's leadership, Ms Warner said further reform is still needed to remove all carve-outs.

"There is more work to do to ensure that all children under 14 are protected by these laws without exception," she said. "We look forward to seeing further leadership from the ACT by removing excluded offences from the reforms."

Recent Closing the Gap data shows First Nations children remain overrepresented in the ACT's justice system, reflecting a wider national issue.

Despite all governments signing the 2020 Closing the Gap agreement — which targets a 30 per cent reduction in Indigenous youth detention by 2031 — many jurisdictions have enacted laws that critics say undermine that goal.

In the Northern Territory, the CLP government controversially lowered the age of criminal responsibility to 10, despite widespread condemnation from human rights, medical, legal, and Indigenous organisations.

In Queensland, the government passed "adult crime, adult time" laws allowing children as young as ten to face life sentences — despite admitting the changes breach international human rights conventions.