Judicial conviction, approached as a logical legal process, is a complex challenge for those who see in the work of the judge something more than a simple application of a legal syllogism. Contemporary doctrines increasingly recognize the active role of judges in the creation of law, which is reflected, at least in theory, in better founded judgments which have a more solid logical structure. From these presuppositions, this article, in a general way, describes the logical-juridical mental process that the tax judge must follow to obtain the long-awaited conviction in their decision, always observing the particular characteristics of the substantive and adjective activity of the tax law. KEYWORDS: Logical-Legal process, tax judge, tax law, conviction, administrative court JEL CODE: D63, E35RESUMENLa convicción judicial, abordada como un proceso lógico jurí­dico, es un reto complejo para quienes ven en la labor del juez algo más que una simple aplicación de un silogismo jurí­dico. Las doctrinas contemporáneas reconocen cada vez más el rol activo de los juzgadores en la creación del derecho, lo cual se refleja, al menos en teorí­a, en sentencias mejor fundamentadas, y con una estructura lógica más sólida. A partir de estos presupuestos el presente artí­culo de manera general describe el proceso mental lógico-jurí­dico que debe seguir el juez tributario para obtener la tan ansiada convicción en su decisión, al observar siempre las caracterí­sticas particulares de la actividad sustantiva y adjetiva del derecho tributario. ABSTRACTJudicial conviction, approached as a logical legal process, is a complex challenge for those who see in the work of the judge something more than a simple application of a legal syllogism. Contemporary doctrines increasingly recognize the active role of judges in the creation of law, which is reflected, at least in theory, in better founded judgments which have a more solid logical structure. From these presuppositions, this article, in a general way, describes the logical-juridical mental process that the tax judge must follow to obtain the long-awaited conviction in their decision, always observing the particular characteristics of the substantive and adjective activity of the tax law. KEYWORDS: Logical-Legal process, tax judge, tax law, conviction, administrative court JEL CODE / CLASIFICACIÓN JEL: D63, E35