Justice secretary Shabana Mahmood has announced that the Probation Service will hire more than 1,000 additional trainee probation officers over the next nine months, as part of a bid for "greater oversight and management" of offenders leaving prisons.
The move came as Mahmood confirmed the government will legislate to allow the release of some categories of prisoner after they have served just 40% of their sentence because of the current shortage of capacity in the UK's jails. As of last week, the nation's prisons were operating at 98.4% capacity, with just over 1,400 spaces remaining.
Mahmood said the move was an "emergency measure", not a permanent change, and would come into force in September to give HM Prison and Probation Service time to plan for the release of additional offenders.
"There is now only one way to avert disaster. I do not choose to do this because I want to, but we are taking every protection that is available to us," she said. "I am unapologetic in my belief that criminals must be punished."
The justice secretary said that the alternative to releasing some categories of prisoner after they have completed 40% of their sentence – rather than the current 50% – would be "the collapse of the criminal justice system and a total breakdown of law and order".
"When prisons are full, violence rises – putting prison officers on the front line at risk," she said. "When no cells are available, suspects cannot be held in custody. This means vanloads of dangerous people circling the country, with nowhere to go.
"The police would have to use their cells as a prison overflow, keeping officers off the streets. Soon, the courts would grind to a halt, unable to hold trials.
"With officers unable to act, criminals could do whatever they want, without consequence. We could see looters running amok, smashing in windows, robbing shops and setting neighbourhoods alight."
This week, former justice secretary Alex Chalk told BBC Radio 4's Today programme podcast that moving to so-called "SDS40" releases had been considered too politically toxic to countenance by the Sunak administration in the runup to the general election.
"You have to win votes," he said. "And that was the calculus that was taxing the prime minister and others."
Mahmood said not all prisoners would be eligible for release after serving 40% of their sentence under the new emergency regime.
People convicted of serious violent offences and handed sentences in excess of four years will be excluded, as will sex offenders and those convicted of crimes related to domestic abuse. Examples include stalking offences, controlling or coercive behaviour in an intimate or family relationship, and non-fatal strangulation and suffocation.
The new rules will not apply to those convicted of the most serious offences. They are already subject to whole-life tariffs, meaning they will never be released, spend two-thirds of their sentence behind bars or have their release determined by the Parole Board.
Mahmood said the decision to hire an additional 1,000 trainee probation officers would support the operation of the new early-release arrangements.
"The measures I have set out are not a silver bullet but they will give us the time we need to address the prisons crisis, not just today but for years to come," she said.
She added that the new government was looking at ways prisons could be built quicker by unblocking the planning system and enacting wider system reform.
She said that a 10-year capacity strategy for the prison estate would be published in the autumn, "in line with the spending review timeline".
The justice secretary said that as part of the measures being set out, the previous government's "dysfunctional and unmanageable" end of custody supervised license scheme would come to an end.
The scheme was launched in October last year to address capacity issues and initially saw prisoners released 18 days early. The MoJ said 10,000 prisoners had benefited from the scheme, which it said had been "repeatedly expanded" since its introduction.