Administering justice in marriage annulment proceedings is a delicate ministerial function of the Church. At stake is the truth of a sacrament and the salvation of the spouses. This requires that such processes be carried out with the maximum diligence and in compliance with deontological criteria and procedural principles. In the new canonical procedural norms, if it is not well applied, there is a risk of endangering the very indissolubility of marriage, the cornerstone of Catholic dogma. This work studies, from a dynamic perspective, the intervention of the Judicial Vicar and the Defender of the Bond in the shortest matrimonial process, analyzing the most problematic novelties introduced by the new canons that govern said judicial procedure. Likewise, an attempt is made to deduce, from the current regulations, the criteria that should govern their actions according to the criteria of the contradictory and due process, with special attention to those issues that pose the most problems in forensic praxis the introduction of libel.