150. In these circumstances, the Court cannot establish whether Supreme Decree 049, which modified Decree 09, was in effect at the time of the facts; furthermore, it considers that the applicable regulation is the Law on the Military Status of Army, Navy and Air Force Officers, whose content and validity at the time of the facts has not been contested. Consequently, the Investigative Council had the obligation to summon, hear and assess the evidence that the alleged victim may have in order to defend himself during this stage of the investigation. However, the Council held the hearing in his absence, without a prior summons, and issued the recommendation to retire him. 151. Subsequently, in the third stage before the Army General Command, the Court notes that in that instance the decision was made to retire the alleged victim once the report from the Investigative Council was received, without any type of process summoning him to defend himself, submit evidence or claims, or present his objections to the report of the Investigative Council. There is definitely no evidence that he was allowed any type of intervention before the decision was presented.127 Within the framework of that decision, Mr. Rosadio Villavicencio was never granted the right to a hearing required by the American Convention, or any way to guarantee its formal aspect, that would allow him to submit arguments and evidence regarding his version of the facts and the offenses that he was charged with. 152. Thus, there is no evidence that during the disciplinary proceedings against Mr. Rosadio Villavicencio, in any manner or at any of its stages, he was allowed to submit arguments, either orally or in writing, to make objections, submit evidence, or that he was permitted any type of procedural activity to guarantee the right to defend himself, apart from the statement given at the beginning of the proceedings, for which he did not receive prior notification of the facts and did not have any legal counsel. 153. Based on the foregoing, the Court concludes that the State violated the right to a hearing and the right to defend himself, enshrined in Articles 8(1) and 8(2)(c) of the Convention, to the detriment of Mr. Rosadio Villavicencio. 154. Regarding the lack of adequate grounds of the aforementioned recommendation by the Investigative Council and the decision of the Army General Command to retire Mr. Rosadio Villavicencio, the Court has pointed out that “the duty to provide grounds is one of the ‘due guarantees’ included in Article 8(1) to safeguard the right to due process.” 128 The Court has indicated that the grounds “are the exteriorization of the reasoned justification that allows a conclusion to be reached”129 and involves a rational explanation of the reasons that led the judge to adopt a decision. Thus, the arguments behind a decision and certain administrative acts must allow knowing the facts, the reasons and the regulations used by the authority to make its decision, in order to rule out any indication of arbitrariness.130 Moreover, it must demonstrate that the arguments of the parties were duly weighed and that the body of evidence was analyzed.131 9 155. In the instant case, the Army General Command, body in charge of making the final decision regarding the retirement of the alleged victim and, therefore, affecting his rights and Cf. Order of the Army General Command, March 3, 1995 (evidence file, folios 82 and 83). Cf. Case of Apitz Barbera et al. (“First Court of Administrative Disputes”) v. Venezuela. Preliminary Objection, Merits, Reparations and Costs. Judgment August 5, 2008, para. 78, and Case of Amrhein et al. v. Costa Rica. Preliminary Objections, Merits, Reparations and Costs. Judgment of April 25, 2018, para. 268. 129 Cf. Case of Chaparro Álvarez and Lapo Íñiguez v. Ecuador. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 21, 2007, para. 107, and Case of Amrhein et al. v. Costa Rica. Preliminary Objections, Merits, Reparations and Costs. Judgment of April 25, 2018, para. 268. 130 Cf. Case of Claude Reyes et al. v. Chile. Merits, Reparations and Costs. Judgment of September 19, 2006, para. 122, and Case of Dismissed Employees of PetroPerú et al. v. Peru. Preliminary Objections, Merits, Reparations and Costs. Judgment of November 23, 2017, para. 171. 131 Cf. Case of Apitz Barbera et al. (“First Court of Administrative Disputes”) v. Venezuela. Preliminary Objection, Merits, Reparations and Costs. Judgment of August 5, 2008, para. 78, and Case of Ramírez Escobar et al. v. Guatemala. Merits, Reparations and Costs. Judgment of March 9, 2018, para. 187. 127 128 35