
The prison population is expected to grow by more than a third in the next decade.
The annual Ministry of Justice projections also expect the number of people on remand - that is, behind bars but awaiting trial or sentencing - would leap 48%.
The report said there would be 15,200 prisoners in June 2036 - a 35% increase from 11,240 in February this year.
The numbers were in line with last year's projections.
The report also said there would be fewer cases before the court, but more serious cases and longer sentences, due to government policy changes.
Remand population on the rise
Currently, 4677 people in prison were on remand - 41% of the prison population. That was projected to reach 6900 by 2036, or 45%.
The rate of increase had slowed over the past year, but people were still spending a long time on remand, Ministry of Justice sector insights general manager Rebecca Parish said.
"Timely access to justice continues to be a priority, with initiatives helping to stabilise remand times in the short-term."
Time spent in remand had stabilised over the last year, but that was "conservatively" projected to increase from 91 days to 110 days over the next decade, the report said.
The number of women entering remand was also on the rise, projected to increase 82%.
Fewer total court cases, more serious cases
While the overall number of cases before court was expected to decrease by 4% in the next decade, there would be a 5% increase in more serious cases, the report said.
"This is driven by new policy and increased prosecution associated with higher frontline police numbers," the report said.
"At the same time, additional frontline police visibility may act as a deterrent for lower-level... offending."
Parish said the numbers reflected the impact of recent law changes, including the Sentencing (Reform) Amendment Act and the Crimes Amendment Bill.
Under the Sentencing (Reform) Amendment Act, more people would be sent to prison, and for longer terms, she said.
The annual projections were vital for informing future resourcing and capacity planning across the justice sector, Parish said.
This story was first published on rnz.co.nz | ![]() |












