To verify the main hypothesis (i.e. the crucial role played by policies) the paper analyse data from a comparative analysis of local contentious interaction with Roma groups in ten Italian towns. The administrative side of State, especially at the local level is unnoticed in most of the literature on urban conflicts. Political opportunity structure is very important, but the main result of the research signals that policy instruments and the way in which are used have a deep impact in the dynamic of contention. When urban conflicts on Roma settlements produce non-negotiable identities, it depends also on public administrations' difficulties to manage compromises and adjustments among the parties. Irreconcilable positions and hard feelings of hostility against Roma and Sinti do not depend on cultural affiliations; they are the outcomes of an institutional environment with a lack of mediation.
The paper enables to situate the assumptions about prejudice and ethnic hostility, explaining them not only through exogenous factors, regardless of the multiplicity of urban contexts, but also taking into account the role played by the local administrations within the dynamics and the historicity of each local conflicts. It also permits to account for mechanisms of diffusion, escalation and scale shift in urban conflicts, trying to avoid the trap of a radical endogenous explanation.