Key facts
- The number of electronically monitored individuals in England and Wales has doubled to 28,700 in five years.
- The government plans to increase annual tagging to 22,000 from 2027 to manage prison capacity.
- A watchdog report found thousands of individuals may not be actively monitored.
- Concerns were raised about contractor performance and a significant shortfall in probation staff.
- The NAO warned that expanding the system without addressing weaknesses risks public safety and wasting public money.
The UK's public spending watchdog has warned that the planned expansion of electronic tagging in England and Wales to ease prison overcrowding risks public safety due to systemic weaknesses. The National Audit Office (NAO) reported that the number of people electronically monitored has doubled to 28,700 over five years, with government plans to increase this further.
The NAO's report raises serious questions about the effectiveness of the system, noting that thousands of individuals may not be actively monitored. As of March 2026, HMPPS was reviewing approximately 8,900 cases, or 24% of those required to be tagged, to determine the extent of unmonitored cases, though the Ministry of Justice (MoJ) suggests a lower figure of around 5,450.
Concerns were also raised about the performance of external contractor Serco, which experienced delays in fitting tags and notifying officials of potential breaches. During one period, the backlog of visits to fit, check, or remove tags peaked at 7,000. Furthermore, an estimated shortfall of about 2,200 probation staff adds to concerns about the system's ability to scale safely.
Gareth Davies, head of the NAO, stated that electronic monitoring is central to managing prison pressures but is not working effectively, creating risks to public protection. Sir Geoffrey Clifton-Brown, chair of the public accounts committee, echoed these concerns, highlighting the government's uncertainty about unmonitored individuals and its capacity to respond to breaches.
Pia Sinha, chief executive of the Prison Reform Trust, described the findings as a cause for concern, cautioning against viewing electronic monitoring as a panacea and emphasizing the need for investment in probation and robust safeguards. The MoJ, however, stated it inherited a failing system and is investing £100 million in electronic monitoring and £700 million in probation to improve performance and public protection.