Corrections says it has no immediate plans to expand Auckland Prison, but being listed on the Fast-Track Approvals Bill will future-proof the facility at Paremoremo.
The prison service's proposal is to amend the facility's designation conditions, so that it can increase the maximum number of prisoners from the current 681 to 1200.
People Against Prisons Aotearoa spokesperson and criminology lecturer Dr Emmy Rakete told Midday Report it was "a bit cheeky" of Corrections and the government to say they had no immediate plans to expand Paremoremo prison.
"Obviously they do, otherwise they wouldn't have put this in there, so that's nonsense."
Rakete was critical of the fast-track legislation in general.
"Paremoremo expansion is just another one of those kind of lumpy bad projects."
She described the prison as "disgusting", under-staffed, and over-crowded.
"It's just not viable to double the size of that prison and expect to get anything other than stabbings, rapes, and deaths.
"If they build it they'll fill it."
It wasn't a question of the building itself, but rather the level of imprisonment the country could sustain, Rakete said.
There had been a trending moderate decrease in prison population for some time which she said was a "good thing".
"Prison is ruinous for people's life trajectories, the less people who are inside, the shorter that people are inside for, the better the outcomes are."
The coalition government had reversed that trend, she said.
"This is really committing to a much more imprisoned future for Aotearoa and it doesn't have to be that way."
Corrections spokesperson Alastair Turrell said it was part of ensuring there was capacity in future for the increasing prison population.
"If approval is granted to increase this designation, Corrections would still need to complete construction work to increase the level of physical fit-for-purpose bed capacity at the site.
"However, amending the designation now means we can respond quicker to any future increases in demand for prison capacity," he said in a statement.
"The project will also support the long-term resilience of our prison network.
"This is particularly important in Auckland, which is a region of high demand," he said.
It was also the country's only maximum-security facility.
Corrections Minister Mark Mitchell said it was a proactive move, despite there being no immediate plans to expand the facility.
It was about planning ahead, he said.
"They're being proactive in anticipation that, Auckland's obviously our biggest centre, if there is a growth in prison numbers and there's the need for additional capacity then that means that they're already ahead of the curve and they're ready to go."
An increase in the Auckland prison population in the short term was expected, he said.
"We are going to see a boost in the prison population, certainly in the short term," he said.
"We're putting victims and public safety at the heart of what we're doing, and that means that we want people that create more victims out of the community and in our prison system where we can then try and rehabilitate them so that they're much safer, making good decisions, when they come back and reintegrate with their communities again."
Mitchell reiterated there were no plans to expand Auckland Prison, and that nothing would go ahead without full public consultation.
He said having the proposal on the Fast Track list gave Corrections the resource to increase numbers at facility.
"It's quite simply about capacity, it's also about the refurbishment, and the upgrades of the cells and the facilities themselves, and, like I said, it's about forward planning."
Mitchell said the Fast Track was a good programme for planning, and signalling investment into infrastructure.
"Corrections have been very proactive, they've identified where they want to be doing this planning, and they've used the Fast Track to do it, and I think that just shows smart planning on their part."
Since there were no immediate expansion plans Corrections was unable to provide information on costs or timeframes, he said.
A total of 149 projects have been selected for fast tracking through the government's new Fast-track Approvals Bill.
Among the housing projects are developments at Plimmerton Farm in Porirua and Silverstream Forest in Upper Hutt, which have previously been controversial.
The scrapped Hawke's Bay dam, the Tukituki Water Security Project may be revived.