New projections suggest that within six years, the number of prisoners locked up but still awaiting trial will be greater than those already sentenced.
The Ministry of Justice has released it's annual report which looked at the long term trends across the sector and predicted the prison population for the next 10 years.
It forecast that by 2029, the overall population would rise by 1300 putting the total at 11,400.
The current population is about 9928 after peaking at 10,100 in November 2019.
The report said the remand population was the "primary driver of growth in the 2019 projection".
The remand population - those in prison who have not been sentenced - had doubled since 2014 and in the past 12 months, increased by more than 25 percent.
It reached a "historic high" of 3734 in November 2019.
That population was predicted to continue on track and would make up 53 percent of the total population by 2029 - sitting at a total of around 6234.
"The increase in the remand population in 2019 far exceeds previous projections. Based on current settings, the remand population is now projected to surpass the sentenced population for the first time in 2026."
The report showed in 2018 the remand population dropped significantly, but the trend did not continue.
"Instead, the average time on remand has increased sharply from December 2018 onwards."
It said people were spending longer on remand because their cases were taking longer to be resolved in courts.
The report listed the below as reasons for the increased numbers.
- Later guilty pleas in the criminal court process leading to more court hearings and creating strain on court resources
- The lack of sufficient resources to deal with the additional court hearings and the reallocation of judges from the criminal to the family jurisdiction resulting in further delays
- An increase in the number of days to the next available court hearing due to workload pressures
- An increase in category three cases, which are more serious and generally require more resources compared to category one and two cases, adding further pressure to case workloads regardless of when the plea occurs.
People on remand do not have access to rehabilitation programmes and the report said that created the potential to increase their likelihood of reoffending - particularly for those who serve their whole sentence on remand.
Those who do move through to the sentenced population face delays in starting their rehab, meaning they have to do more time while they are prepped for parole - increasing both the number and the amount of time people spend in custody, growing the total population.
The 2019 projection estimated the sentenced population would decline from approximately 6400 to 5300 over the next 10 years.
But if that number does not reduce as predicted there could be problems for the criminal justice system.
The report said "strong upward pressures" on the total prison population would impact the Department of Corrections high security accommodation and not allow the separation of remand and sentenced prisoners.