The need for additional prison spaces in England and Wales has been a growing issue for ministers in recent years. When Labour returned to power in July last year, a system on the brink of full capacity was a flashing red light for new ministers that prompted a further relaxation of early-release rules for prisoners.
In 2021, the Johnson government pledged to build 20,000 new prison places by the middle of this decade, through a mixture of new-build prisons, expansion of existing prison buildings, refurbishments and infill developments of temporary cell accommodation.
In December 2024, the National Audit Office reported that HM Prison and Probation Service no longer expects to deliver that capacity until 2031. As of September last year, only 6,500 of the places had been provided.
As the timescale for the programme has expanded, so has the cost. The programme's original estimated approved funding was £5.2bn, however the NAO said HMPPS and the Ministry of Justice's latest expectations are that the eventual cost will be between £9.4bn and £10.1bn. September's collapse of major contractor ISG has also introduced new expenses and delays.
Last month, senior leaders from the Ministry of Justice and HMPPS answered questions from members of the Public Accounts Committee about the NAO's report, Increasing the capacity of the prison estate to meet demand. Here are six things we learned from the session:
Project Speed failed to deliver
MoJ perm sec Antonia Romeo told MPs that delays related to planning played a "massive role" in the prisons programme missing its original mid-2020s target for delivering the additional capacity and the consequent "significant increases" in costs.
She said that when the original commitment was made, three of the proposed six new prisons already had planning permission. Two more prisons have subsequently been granted consent, but approval for the final new prison is the subject of a judicial review.
Romeo said that prison – HMP Garth in Lancashire – had now been in planning for 40 months. "There is no way that that could have been predicted," she said. "Is it a major failure that a prison has spent that long in planning? I would say that it is just part of the process of building major infrastructure programmes."
The perm sec was asked whether the delays in the planning process for some of the new prisons should have been "fairly foreseeable".
She said that the original timetable for the programme had been set out during a joint HM Treasury and Cabinet Office initiative called "Project Speed", which was aimed at delivering infrastructure more rapidly.
"All infrastructure projects at the time were working on the basis that Project Speed would deliver," she said. "That was not, in fact, implemented, so as a result there were delays there."
Romeo said that, in retrospect, it would have "been better not to have planned for Project Speed to have delivered what it said it would deliver".
There is expected to be a shortfall of around 6,000 prison places by 2027
At the end of October last year, there were 85,900 people in prison, a 3% decrease since September 2024, following the early release of around 3,000 prisoners to manage severe capacity issues.
Romeo told MPs that the early-release reforms introduced by the government, which allow some categories of prisoner to be freed after serving only 40% of their sentence, have improved projections of the prison-places shortfall.
The NAO previously suggested a central estimate was that there would be a shortage of 12,000 prison places by 2027. Romeo told MPs that the early-release changes, known as SDS40, meant MoJ now projected the shortfall as being "about half" the 12,000 figure.
ISG collapse will add £300m to the cost of the prisons programme
Major construction contractor ISG went into administration in September last year. At the time it held government contracts estimated at £1.84bn.
Jim Barton, executive director of HMPPS Change, told MPs the insolvency was expected to add around £300m to the cost of the prisons programme. Barton said ISG had involvement in the delivery of some 3,500 prison places and that those projects were now facing delays of up to a year.
HMPPS director general Amy Rees said the service's exposure to ISG's collapse was "more on the maintenance side", where the firm was involved with work to bring cells up to fire safety standards.
Rees said the demise of ISG could mean HMPPS is not able to meet a commitment to make some 23,000 currently-occupied cells fire safety compliant by 2027. She said affected cells would be taken out of use if they had not been remediated by the deadline.
There's a £2.8bn prisons-maintenance backlog
In addition to the cost of building the 20,000 new prison places, MoJ and HMPPS are facing a significant backlog in maintenance funding.
The NAO said HMPPS had spent an average of £173m a year on maintenance between 2020-21 and 2023-24 – significantly below the £649m a year maintenance-funding requirement that HMPPS estimated was needed in the 2020 Spending Review.
Romeo told MPs that £2.8bn is needed to "totally remediate" the prison estate. "In the current SR, we were given, specifically, £220m and £300m," she said. "We can all do the maths. We are going to need a lot more money in the next spending round to begin to make inroads into the maintenance."
Rapid Deployment Cells are over-budget and not so rapid
The introduction of additional cell capacity at existing prison sites is set to account for 1,700 of the 20,000 planned prison places being delivered.
Prefabricated units called "Rapid Deployment Cells" have an anticipated lifespan of around 15 years and are designed to be self-contained and suitable for lower-risk prisoners. So far 770 units have been constructed.
Last month's PAC session heard that while the cost of the overarching prisons programme have increased by 80%-93%, the cost of the RDCs has increased by around 250%. According to the NAO, delivery for the first 1,000 RDCs has slipped from 2022 to 2026.
Barton told MPs that three factors were behind the increasing cost of RDCs: design refinements; site conditions; and delays linked to "nutrient neutrality" regulations that apply in some parts of England. Those obligations require developers to offset the impact of additional grey water created by projects by buying nutrient neutrality credits.
"The challenge that we have in some of our projects is that there are no schemes established for us to be able to offset the impact of those projects by buying nutrient neutrality credits," he said. "That has led, in the worst case, to delays of close to a year at some of those RDC projects, because we simply cannot lawfully proceed to full construction until we have been able to remedy those nutrient neutrality issues."
Barton told MPs that the delivery of around 300 cells had met with "a really material delay" because of nutrient neutrality requirements.
About one-quarter of prisoners share their cell
HMPPS director general Rees told MPs that while most prison cells could physically accommodate two prisoners, only just under a quarter of cells currently houses two inmates.
"Crowding levels at the moment are at 23.6%, so that means about a quarter of the estate are living in a cell designed for one person with two people," she said. "To be clear to this committee, that means that someone has to defecate where someone else eats their meal. They were designed for one person; there is an open toilet in that cell."
Rees said that policy for new prisons has been to build cells that were more suitable for two inmates and which have a separate bathroom and shower.
She said that while HMPPS was keen to "eliminate crowding", ending the use of double-occupation cells was not necessarily the overarching objective. "There is quite a lot of evidence that sharing for some people is a very good protective factor for violence, self-harm," she said. "But we definitely try to reduce crowding."