The rate of South Australians behind bars has increased by almost a third in the past decade, prompting calls to fund alternatives to "harmful" and ineffective prisons.
The state's incarceration rate has increased by 32 per cent over ten years - second only to Queensland - despite programs aimed at reducing recidivism, found a report released by the Justice Reform Initiative on Tuesday.
The alliance's executive director Mindy Sotiri said prisons are "harmful, fail to reduce crime or address the drivers behind it and increase the likelihood of reoffending".
They are also relatively expensive, compared to the cost of home detention or preventing offending in the first place.
Each year, South Australian taxpayers spend $374 million to operate the state's prisons and that figure will continue to rise as the incarceration rate goes up.
Dr Sotiri called on the Malinauskas government to scrap its $180 million expansion of the Yatala Labour Prison and instead invest money in community-led organisations and alternatives to help break the cycle of incarceration and recidivism.
"Crime prevention and support of people at risk of imprisonment is best carried out in the community where the drivers of crime can be addressed - not in an enormous new prison which will further entrench cycles of re-incarceration, ultimately failing to make the community safer," she said.
The report praised the SA government's 20by26 strategy to reduce recidivism by 20 per cent as a "fundamental shift" in corrections policy and resulting in recidivism rates among the lowest in Australia.
It also applauded the government's recent commitment to boost funding to reduce Indigenous incarceration.
But Dr Sotiri says more money should be going to Aboriginal-led community organisations rather than to services run by the Department of Correctional Services, which received the bulk of the funding.
"This report shows there are dozens of community-led alternatives achieving remarkable results in breaking cycles of disadvantage, particularly First Nations-led organisations," she said.
"But too many of these services are under-resourced and unable to meet demand, meaning only a fraction of people at risk of offending or reoffending can access them."
Indigenous South Australians are 16 times more likely to be jailed than their non-Indigenous counterparts, while more than half of all children in detention are of Aboriginal and Torres Strait Islander background, despite making up just 2.4 per cent of the population.
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