Call for nominations Joint Expert Group on Prison Overcrowding and Probation Netwidening (EuroPris & CEP)

If you are interested in becoming a member of this Expert Group please submit a nomination on behalf of your jurisdiction by 26 June 2026. Please note that the first physical meeting of the Expert Group is to take place 8 December 2026 in The Hague, The Netherlands.

Background

The launch of the Joint Expert Group has been initiated by CEP and EuroPris to address the issues related to increasing number of people in prison and under probation supervision.

For prison, overcrowding remains one of the most persistent and structurally embedded challenges across European prison systems. In many jurisdictions, prison populations continue to exceed official capacity, placing significant strain on infrastructure, staff, and the delivery of rehabilitative services. Overcrowding undermines safe and humane detention conditions, exacerbates tensions and violence, and limits access to healthcare, education, and reintegration support. It also reduces the system’s ability to respond effectively to complex needs, including mental health and substance use disorders.

For probation, netwidening creates a structural paradox: a community sanction that now supervises more people than prison. According to the latest data, in 2024 there were approximately 1.4 million persons under probation supervision compared to 1.0 million people serving prison sentences. A broader and more appropriate use of alternatives throughout the criminal process is needed, at national and European levels, to reduce netwidening and avoid the expansion of mass supervision.

While often driven by broader criminal justice policies and sentencing practices, overcrowding and netwidening are also linked to excessive use of alternatives to custody, limited early release mechanisms, and inefficiencies at different stages of the criminal process. Addressing prison overcrowding and netwidening, therefore requires coordinated, system-wide approaches that combine policy reform, operational adjustments, and stronger alignment between custodial and community-based measures.

The aim of this expert group is to strengthen understanding and responses to fight the phenomenon of the prison overcrowding and netwidening in probation by translating shared knowledge into practical, system level action. This includes clearer decision-making and triage to prevent unnecessary use of prison or probation and ensure interventions are proportionate and well-targeted. The group aims to share knowledge and good practices, analyse the impacts of these challenges, strengthen EU‑wide cooperation, and promote safeguards that support the effective use of prison sentences as well as alternatives to custody.
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