Lay knowledge and epistemic justice in mental health: a critical analysis of the peer support worker in the Spanish State.

This essay critically examines the figure of the peer support worker within the mental health system of the Spanish State as a dispositif situated in the tension between the transformation of epistemic hierarchies and the risk of institutional co-optation. Drawing on our experiences and research in the field of critical medical anthropology and human rights in mental health, together with and from the activisms of the Mad Movement in the Spanish State, we analyse how this professional figure simultaneously embodies a promise of epistemic power redistribution and the danger of neutralisation by the hegemonic biomedical model. We argue that epistemic justice in mental health requires the radical transformation of the material, relational, and institutional conditions that have historically sustained the delegitimation of experiential knowledge. Through a genealogical analysis of the peer support worker and its processes of institutionalisation, we identify the structural conditions that determine whether its incorporation can effectively challenge dominant regimes of truth or, conversely, operates as a mechanism of legitimation that formally incorporates diversity without transforming existing logics of power. We conclude by proposing a framework of four dimensions of political intervention: strengthening epistemic fraternities and Mad Movement networks as community assets, transforming professional cultures, contesting regulatory frameworks, and articulating local processes of knowledge co-production.