Between the Inquisitorial Judge and the Rights-Based Judge: The Judge of Guarantees in the Spanish Criminal Justice System

Abstract

This study examines the legal institution of the judge of guarantees within the Spanish criminal procedural system, focusing on its concept, characteristics, and the theoretical foundations that justify its implementation. It offers a theoretical and normative analysis of the judge of guarantees as a figure responsible for ensuring the legality of criminal investigations and safeguarding the fundamental rights of the parties, distinguishing this role from that of the traditional investigating judge. Furthermore, the article explores the historical evolution of the Spanish criminal process from its inquisitorial origins to current reform proposals, emphasizing the exceptional incorporation of the judge of guarantees under Organic Law 9/2021 and its potential consolidation through the Draft Criminal Procedure Act. The research concludes that the judge of guarantees serves as a key instrument of penal garantism and as a structural safeguard of judicial impartiality in a democratic state governed by the rule of law.