Since the late 1980s, following the transition to democratic rule in Latin America, criminal courts all over the continent have been going through a process of continuous reform. Reformers introduced an adversarial-based procedural system, arguing that it would guarantee due process and greater transparency and accountability. However, in recent years, the emphasis of this reformist narrative has changed from expanding defendants' rights towards improving the efficacy of the system. This paper explores how the original principles of transparency and accountability have been upheld in criminal courts in one of the first areas of jurisdiction to implement those changes: the Province of Buenos Aires. Based on an analysis of data from forty-five in-depth interviews with key informants and court observations, this paper explores how the reforms developed a managerial rationality in criminal courts that may undermine the due process in Latin American jurisdictions that have undergone similar democratic reform processes.