Electronic monitoring system faces challenges

The National Audit Office (NAO) has highlighted significant flaws in the electronic monitoring system used by Her Majesty's Prison and Probation Service (HMPPS). While there has been a rapid expansion since 2021, with around 29,000 individuals tagged, uncertainties remain about the effectiveness of monitoring. Alarmingly, many people who are legally required to wear tags may not be actively monitored, raising serious questions about public safety.

The system, designed to manage offenders in the community, is set to face increasing demand starting in September 2026 as the government attempts to alleviate pressures on prison capacity. In light of this, the NAO has called on the Ministry of Justice (MoJ) and HMPPS to take a comprehensive approach to address existing problems, enhance performance monitoring, and devise robust contingency plans. The NAO emphasised that “further expansion of the electronic monitoring system will not be efficient or effective unless the MoJ and HMPPS work with partners to address weaknesses in governance, data quality and system-wide inefficiencies to support a more reliable and responsive service.”

The backdrop to this scrutiny includes a troubling history of poor performance from one of the external contractors, Serco. An example of this is from August 2024 to July 2025 when many individuals were not tagged promptly, and notifications for potential breaches were delayed. This inefficiency culminated in a backlog of visits for fitting, checking, or removing tags, reaching an alarming peak of 7,000 visits in October 2024 before stabilising to fewer than 400 a month later. Despite some improvements since then, the NAO report warns that these supplier-specific enhancements are not enough; systemic changes are crucial.

Furthermore, by March 2026, HMPPS was in the process of reviewing around 8,900 cases, representing 24% of those required to be tagged, to assess unmonitored individuals. The lack of timely information has also hindered police and probation officers in responding to breaches, with a high volume of alerts lacking clear prioritisation, resulting in almost half of recorded outcomes leading to “no further action.”

The long-term plan includes increasing tagging numbers significantly from 2027, with the government preparing to allocate up to £175 million for this initiative from 2026 to 2029. This funding aims to develop new technologies and data management systems while also focusing on specific interventions like monitoring domestic abuse offenders more effectively.

Nonetheless, staffing remains a critical issue, with an estimated shortfall of around 2,200 probation officers as of March 2026. Without addressing these fundamental issues, the ambitions for expanding electronic monitoring could not only be ineffective but may also exacerbate existing vulnerabilities in public safety.

As Gareth Davies, head of the NAO, articulated, “Electronic monitoring is central to managing pressures on prisons, but it is not working effectively, creating risks to public protection. Improvements are required to ensure that those who should be monitored are monitored and that breaches are responded to effectively.” Only time will tell if the MoJ and HMPPS can implement the necessary reforms in time to prevent a crisis from escalating into a threat to public safety.