As per a recent report, plans to rapidly expand electronic tagging to ease the suffocating pressure on UK prisons will put public safety at risk unless urgent fixes are made to an already buckling system, the government’s spending watchdog has warned.A stark report from the National Audit Office (NAO) has cast serious doubt over the effectiveness of the current tracking network. Over the last five years, the number of people under electronic surveillance in England and Wales has doubled to 28,700. As ministers scramble to handle a severe prison capacity crisis by managing more offenders in the community, that number is expected to swell even further, with an estimated 22,000 people being tagged each year from 2027.However, the NAO revealed a chaotic picture behind the scenes, warning that thousands of individuals required to wear a tag may not actually be actively monitored. The spending watchdog has called on the Ministry of Justice (MoJ) and HM Prison and Probation Service (HMPPS) to immediately draw up robust backup plans.The true scale of the blind spot remains a point of contention within the government. As of March 2026, HMPPS was reviewing roughly 8,900 cases—representing nearly a quarter of all tagged individuals—to figure out exactly how many had slipped off the radar. The MoJ has downplayed that figure, suggesting its own data shows the number of unmonitored cases sits closer to 5,450.A major source of friction highlighted in the report was the early performance of Serco, an external contractor hired to run the service. The NAO concluded that throwing more money at the electronic monitoring system would be neither efficient nor effective until the MoJ and HMPPS fix deeply ingrained issues with data quality, weak governance, and systemic delays.Despite these warnings, the government has already earmarked up to £175m to fund the expansion between 2026 and 2029.Gareth Davies, head of the NAO, urged the government to halt and fix the foundations before building higher. “Electronic monitoring is central to managing pressures on prisons, but it is not working effectively, creating risks to public protection,” Davies said. “The MoJ and HMPPS should address the inefficiencies and risks identified in our report before expanding electronic monitoring.”Sir Geoffrey Clifton-Brown, chair of the public accounts committee, echoed those anxieties, calling the findings deeply concerning. “The government does not know for certain how many people who should be tagged are being left unmonitored, nor does it have the information or capacity to respond quickly to breaches,” he said, warning that the expansion risks wasting public money while leaving communities vulnerable.Criminal justice experts are also urging ministers not to view the technology as a silver bullet for overpopulated jails. Pia Sinha, chief executive of the Prison Reform Trust, described the findings as a major cause for concern. “Expanding the use of tagging without addressing wider pressures risks undermining both public confidence and public safety,” Sinha said, adding that tracking technology only works when backed by proper probation investment and robust safeguards that help people rebuild their lives without reoffending.Defending its strategy, an MoJ spokesperson said the current administration had inherited “a failing tagging system with record backlogs,” but pointed out that tag installation rates have risen by nearly 50% since 2024.“Public protection is our priority,” the spokesperson said, highlighting a £100 million chunk of funding dedicated specifically to electronic monitoring, tagging offenders before release for the first time, and setting up new victim-alert systems to drive down the number of unmonitored cases. The ministry also pointed to a wider £700 million injection into the probation system aimed at hiring and training a new wave of officers to handle the strain.
