Prisoner numbers have declined nationally, but not in Tasmania.
The average daily number people in custody in Australia fell by about 1.3 per cent to 42,506 in the September quarter, according to the Australian Bureau of Statistics.
The biggest state, New South Wales, cut prisoner numbers by 4 per cent and Victoria by 2 per cent.
Tasmania was stable at 645.
The ABS suggested the coronavirus pandemic and related restrictions might be affecting the figures.
"There have been government restrictions across the states and territories due to COVID-19 since March 2020," it said.
"The restrictions may have had an impact on criminal activity and the justice system."
Tasmanians were less likely to be imprisoned than Australians as a whole.
Tasmania's stable imprisonment rate of 150 prisoners per 100,000 adults was significantly lower than the national rate of 212, which fell from 215 in the previous quarter.
Victoria (136 and falling) and the ACT (120 and rising) had the lowest imprisonment rates, while Western Australia (321) and the Northern Territory (985, not a misprint) had the highest.
Nationally, 92 per cent of prisoners were male and 8 per cent female.
The figures were a mixed bag for indigenous Tasmanians.
They were much more likely to be prisoners than Tasmanians as a whole, with an imprisonment rate of 807 per 100,000 adults, compared with the rate of 150 for all Tasmanians.
The indigenous imprisonment rate had increased by 2 per cent.
The better news was Tasmania had easily the lowest indigenous imprisonment rate in the nation, with the next lowest - the ACT with 1801 - more than double Tasmania's rate.
Western Australia (3771) and the Northern Territory (2898) had the highest indigenous imprisonment rates.
Tasmania had 2088 people serving community-based corrections orders.
That was up by 7 per cent.