Sentencing and bail crackdowns may be costing billions of extra dollars in taxpayer funds as the cost of maintaining prisons spikes.
Australia's average daily prison population is at its highest level in eight years, according to data released on Wednesday by the Productivity Commission.
More than 45,000 people on average were locked up each day in 2024-25, a rise of 5.9 per cent.
Driving the increase in prisoners is an uptick in recidivism with 44.5 per cent of inmates released returning to prison within two years, the highest level since 2019.
The growing price tag of the swelling prison population is more than $5 billion per year, or about $13.7 million a day.
The yearly sum has grown more than $1.5 billion in the last decade.
While prison numbers and costs may be escalating, many crime rates are coming down.
Household crimes like property damage, break-ins and car thefts have all dropped in the past 10 years, according to the Australian Bureau of Statistics crime victimisation database.
Most categories of physical crimes have also decreased, including assaults and robberies, while incidents of sexual assault have slightly risen.
With crime rates easing, tough-on-crime policies enacted by various state and territory governments may be behind the persistent swelling of prison numbers.
The Queensland coalition government enacted "adult time for adult crime" in 2024 after a 17-year-old fatally stabbed mother Emma Lovell during a Boxing Day home invasion in 2022.
Victoria followed suit late in 2025 and also introduced the "toughest bail laws in Australia" by removing the principle of detention as last resort for young offenders.
Former national children's commissioner and now Justice Reform Initiative spokesperson Anne Hollonds said on Friday record funds are being poured into a system that fails to reduce crime.
"In Victoria, youth detention numbers were falling just two years ago," she said.
"Now we are seeing a rapid reversal as punitive policies take hold. This is the same failed path we have already seen elsewhere."
NSW tightened bail laws in 2024 by making more accused offenders prove why they should not be detained and strengthening the presumption against bail for domestic violence and youth matters.
