Blueprint for Co-production: The United Kingdom Longitudinal Linkage Collaboration (UK LLC) Citizen Panel Case Study

Background: As data-intensive health research expands, questions around legitimacy, trust and social license have become central to research governance. Citizen Panels and other forms of public engagement groups are increasingly used to incorporate public perspectives into decision-making, yet there remains limited empirical evidence on the conditions under which such panels enable genuine, non-extractive coproduction, particularly within national research infrastructures. This paper examines the UK Longitudinal Linkage Collaboration (UK LLC) Citizen Panel as a case study of deliberative public involvement embedded within a Trusted Research Environment, following an evaluation project led by a peer-researcher. Methods: The study employed a peer-led qualitative design. Semi-structured interviews were conducted with 12 participants (six UK LLC staff and six Citizen Panel members) and analysed using thematic and comparative analysis. The evaluation was conceived and conducted by a Citizen Panel member with academic oversight, enabling independent assessment of co-production processes from a public standpoint. Findings were interpreted in dialogue with deliberative democracy and power theory literature. Results: The Citizen Panel was an experimental iterative public dialogue emphasising co-creation, continuous learning and reflection and involvement of marginalised groups. Genuine co-production in the Citizen Panel was enabled by four interdependent conditions: structural independence of the panel, high-quality independent facilitation, inclusive and accessible meeting design, and iterative institutional responsiveness. Trust emerged as both a prerequisite and an outcome of these conditions. However, co-production was constrained by early role ambiguity, high cognitive and linguistic complexity, and limited visibility of impact for Citizen Panel members. While institutional influence was substantial, insufficient feedback mechanisms weakened participants’ ability to recognise their contribution. Conclusion: The UK LLC Citizen Panel demonstrates that non-extractive co-production is achievable within complex health research governance, but only when supported by sustained resourcing, independent facilitation, and closed accountability loops. The paper proposes a transferable, cyclical framework for non-extractive co-production, offering practical design principles for policymakers, funders, and research infrastructures seeking to embed meaningful public involvement in data governance.