To properly address First Peoples' over-incarceration and reduce interactions with the criminal justice system, community-led solutions and early stage prevention must come first, Just Reinvest NSW's new chief executive says.

Previously the organisation's head of advocacy and engagement, Gomeroi man Ian Brown has been appointed to the role.

Just Reinvest NSW (JRNSW) is a non-profit which works collaboratively with communities to support and develop 'justice circuit-breakers', alongside strategic partnerships with Aboriginal organisations, government, service providers, research institutes and others.

Core to their work is diverting Aboriginal people away from the criminal justice system, from a community-led, place-based and data-informed position.

They work with 10 communities across the state.

"Prevention is always the best answer to reducing," Mr Brown told National Indigenous Times.

"Communities have always had the answers," he added.

Earlier in his career Mr Brown has held senior roles in the NSW Department of Communities and Justice and in the not-for-profit sector.

Wiradjuri man Geoff Scott had served at JRNSW chief executive of since February 2024.

Leading advocacy and engagement at JRNSW Mr Brown headed work on its government relations, and partnerships with Aboriginal communities as well as securing investment into community-led just reinvestment efforts.

JRNSW operates an initiative in Moree, Mr Brown's home community, where he also led the work there.

In cases where people are starting off at a disadvantage, it shouldn't mean an unavoidable path towards being criminalised or penalised, Mr Brown outlined.

Working with Mounty Aboriginal Youth & Community Services in Mt Druitt, on Dharug Land, in Western Sydney, Justice Reinvest engaged with young people to get them Opal Cards — NSW public transport smartcard tickets.

At Mt Druitt, a lot of young First Nations peoples' touch points with police came when accessing public transport.

It's a simple example of grassroots success already making a difference.

In other areas they've engaged in efforts to increase access to getting a drivers licence.

JRNSW also work in diversion, though broadly look at supporting 'sustainable systems'.

"I am honoured to lead an Aboriginal-led organisation that has shown what justice reinvestment can achieve in our communities," Mr Brown said.

"The root causes of over-incarceration are largely systemic, and so are the solutions.

"Place-based, community-led and data-driven justice reinvestment, supported by collaborative leadership with government can redirect resources towards prevention, early intervention, and Aboriginal self- determination."

JRNSW chair Blake Alan Cansdale said the organisation were pleased to announce Mr Brown's appointment.

NSW heads to the polls in March for its state election.

While JRNSW doesn't depend on government funding, instead being supported by private philanthropy, Mr Brown explained, he said a "funding cliff" for the majority of communities undertaking justice reinvestment around the state approaches on June 30.

There are encouraging opportunities if the government backs a community-led approach, he said, with JRNSW working on encouraging this and working with governments to see the value, fund it and resource it.

Last month, a JRNSW report estimated overrepresentation of First Nations people in the criminal justice system cost NSW more than $700 million in a 12 month period between 2024-25: $559 million in relation to adults, and $159 million in relation to children.