While French jails are facing the double-bind of an increasing number of prisoners to manage efficiently, and pressures to humanize their treatment, the development of judicial procedures and the role of legal professionals in the daily functioning of the prison changes practices of custody. Through the ethnographic survey of two jails (observations and interviews with prisoners, staff, parole judges, lawyers, etc.), the dissertation contributes to a sociology of institutions and of law in action. It investigates the often contradictory aspects of law in prison : a tool of mass management and of individualization of sentences ; an expression of the coercive power and a guarantee of the rights of the administration's subjects ; a neoliberal framing of reentry and a fundamental reference to human dignity. The outline follows the prisoner's trajectory and various moments of his evaluation (intake, disciplinary hearings, parole boards) : these practical uses of law are embedded into interactions between agents of the institution and their clients (men, mostly young, from lower socio-economic backgrounds and belonging to racial minorities). Multiple professional fields (custody, the judicial, the social) are involved, but also moral feelings pertaining to how notions like dangerousness, responsibility or vulnerability are framed in the public sphere. Circulating between different scales (the local jail, the prison administration, public policies) this research offers, through the case study of prison, a contribution to an anthropology of the State.
