Hundreds of court hearings have been postponed at the last minute after ministers introduced emergency measures to deal with overcrowded prisons. Operation Early Dawn, triggered on Wednesday, means some suspects will be released on bail, rather than sent to a cell, because their trial will be put off. Suspects’ first appearances before magistrates after they have been charged with a crime are also likely to be affected. Details of the measures emerged as Keir Starmer told Rishi Sunak during parliamentary exchanges to stop trying to give “get out of jail free cards” to criminals. The operation, which is expected to last at least a week, is in addition to an early release scheme under which some convicted criminals are being released to a home curfew to free up cells. It remains unclear how many suspects will be bailed under the operation now in force across England and Wales. Whitehall sources said some bail hearings would be delayed for as little as a day. There were 1,238 prison places available on Friday, according to the latest figures. On Thursday, the government triggered Operation Safeguard, a crisis measure to use police cells to house prisoners. Tom Franklin, the chief executive of the Magistrates’ Association, said his members were very concerned about the further delays and the lack of information from the Ministry of Justice. “Every case that is delayed has real-life consequences for victims, witnesses and defendants – and leads to magistrates and court staff sitting around waiting, rather than administering justice. That is a waste of resources, at a time when there are already large backlogs. It demonstrates the parlous state of the criminal justice system and the need for an injection of more resources at every stage of the justice process.” The Law Society of England and Wales president, Nick Emmerson, said victims, witnesses, defendants and lawyers had turned up at courts across England only to find out that their cases have been delayed. “What is crystal clear is the prison spaces crisis is a consequence of the government’s approach to justice including over a decade of underfunding of our criminal justice system, which also sees chronic shortages of judges and lawyers, huge backlogs of cases and crumbling courts,” he said. At prime minister’s questions, Starmer asked Sunak for assurances that serious offenders would not be freed from jail early as part of a government effort to cut overcrowding. He raised a report released by the prisons watchdog, Charlie Taylor, on Monday, which found that a domestic abuser who posed a risk to children had been freed under the scheme. Sunak defended the scheme, saying there was an “absolute governor lock” on who was put on it. “No one should be put on this scheme if they are a threat to the public,” he said. “Let me be crystal clear. It does not apply to anyone serving a life sentence, anyone convicted of a serious violent offence, anyone convicted of terrorism, anyone convicted of a sex offence.” Labour said Sunak should correct the record, given Taylor found that high-risk offenders had been released. A spokesperson for Starmer said: “I think it’s perfectly reasonable for people to expect to get a straight answer from the government as to exactly who is being released, what the criteria are and to be transparent … we still haven’t had that provided. I’m sure the prime minister would never want to [mislead the house] and would want to look to correct the record as soon as he can.” Labour would look to scrap the government’s early release scheme, a party spokesperson said, while adding it was “under no illusion” it could do this immediately if it won power. Downing Street denied reports claiming that prisons were officially full and defended government measures to cut overcrowding. Asked whether it was fair to say the estate had run out of space for offenders, the prime minister’s spokesperson said: “No. This is an existing operation that is used from time to time to manage immediate localised pressures on the prison estate.” He said the government was “clear and categorical” that the worst offenders should be locked away for “as long as it takes to protect the public”.