The report found that 37% of all deaths among prison leavers supervised by probation in Wales in 2024-25 were drug related. That compares with just over a fifth (21%) of deaths in this category across England and Wales as a whole, or 131 out of 620 deaths. In Wales, 19 of the 52 people who died were drug poisonings where the intent was "undetermined", a figure Dr Jones said was "substantially higher" than the England and Wales average.
Speaking to BBC Wales, Dr Jones said the research drew on UK government data, including Freedom of Information requests. "The added shock value to this is that these data point towards some systematic failures with incredibly tragic circumstances and consequences," he said. "Yet there isn't really a particular debate or discussion ongoing at the moment about these deaths, and indeed their causes, and how we might actually find a solution to them."
Jones noted that responsibility for tackling substance use, housing, education and local government is devolved to the Welsh government, while criminal justice in Wales is controlled by Westminster. "So what tends to happen is that criminal justice matters can often fall between the gaps between debates in the Senedd and debates in Westminster," he added. He said the report raised "important questions about the current devolution settlement and whether the Welsh government has the powers and levers necessary to address the underlying causes of many of the challenges facing Wales", adding: "Only by confronting the realities highlighted throughout this report can politicians and policymakers hope to overcome the many challenges facing communities across Wales."
The report also found that homelessness among former prisoners in Wales is continuing to rise. The number of prison leavers supervised by Welsh probation services who were recorded as rough sleeping on the day of their release rose by 24% in 2025-26, with 695 people in that position. More than a third (39%) of all custodial sentences given to women in Wales in 2025 were for offences related to thefts from shops, while people from black ethnic groups remained the most overrepresented ethnic group in the Welsh prison population in 2025, with 58 black people from Wales in prison per 10,000 of the population compared with 15 white people.
David Bennett, from Wallich, Wales's largest homelessness charity, said most drug-related deaths "are preventable if we treat drug use as a health, not criminal justice, issue". "Housing, health and justice need a joined-up approach," he said, adding that without coordinated support prison leavers were "being set up to fail". "The war on drugs hasn't worked," he added.
A Welsh government spokesperson said: "Every drug-related death is a tragedy. We are working closely with health boards, local authorities, Public Health Wales and other key partners to reduce the harms caused by substance misuse, focusing on early intervention, prevention, treatment and recovery support." The spokesperson added that the findings "strengthen the case for the full devolution of justice to Wales", and that bringing responsibility for justice into line with devolved services "would enable a more effective and joined-up approach to improving outcomes, reducing reoffending and building safer communities across Wales".
A Ministry of Justice spokesperson said: "We inherited prisons in crisis but we're acting on all fronts, including by reducing the number of women in custody through investment in community services and cutting the flow of drugs into prisons. In Wales we invest more than £3.4m into services which work across prisons, probation and courts to help support prison leavers overcome their addiction." They added that prisoners at risk of becoming homeless can be offered temporary accommodation by the prison and probation service.