Restorative justice represents a method of conflict management that calls for an in-depth exploration into practices, including their meanings, foundations, anthropological motivations, and ontological assumptions. This article addresses the critique that restorative justice flattens the legal framework along a horizontal axis, thereby undermining penal institutions and their mediating function. I will examine what a horizontal approach to conflict management entails and propose a conception of law that is both horizontal and institutional – one in which restorative justice embodies the human dimension of criminal law while preserving its guarantees. This article constitutes the first part of a broader study on restorative justice and explores the possibility of integrating restorative practices into contemporary criminal law, following the so-called “broad-sense restorative justice” model.