Starting from an ethnography within the State Secretariat for Migrations in Switzerland, this article addresses the issue of discretion in law enforcement by analyzing the conditions in which Swiss asylum caseworkers make their decision. This article argues that social and legal constraints frame caseworkers' practices and favor a strict interpretation of the law when implementing it. If evolutions of legislation have indeed strengthened the law, there are also incentives for strictness through the controls of superiors and peers, as well as through the secondary implementation rules created within the office to orient caseworkers' practices. Nevertheless, this article also shows that the position of the individual caseworkers in the institution, their institutional symbolic capital, the role of their superiors, the group pressure they experience, the countries from which the asylum demands they process originate, as well as caseworkers' institutional socialization, structure their perception of the room for maneuver they can exercise.