in this case had mentioned that the State of Costa Rica recognized that the alleged victims had exhausted the remedies available under the laws of Costa Rica to contest the judicial sanction that had been imposed. They indicated that, in any case, in addition to the time-barred and inadmissible nature of the objection filed by the State, the fact that, initially, the latter had upheld a position in favor of admissibility in which it recognized that the domestic remedies had been exhausted gave rise to the principle of estoppel. Subsidiarily, they indicated that the State had not proved when, how or why the remedy of unconstitutionality would have been an appropriate remedy against the norms of the Criminal Code to prevent the alleged victims from being subject to criminal proceedings. They added that it was not possible to file an action of unconstitutionality against the definition of the offenses of defamation or libel by the press established in articles 147 of the Criminal Code and 7 of the Printing Act because, once the Supreme Court of Justice had handed down the final judgment convicting the alleged victims, it would have been impossible to file the action of unconstitutionality, because to do so, Costa Rican law required the existence of ongoing proceedings. 24. The Court recalls that Article 46(1)(a) of the American Convention establishes that admission by the Commission of a petition or communication lodged in accordance with Articles 44 or 45 requires that the remedies under domestic law have been pursued and exhausted in accordance with generally recognized principles of international law. 13 However, this supposes not only that such remedies must exist formally, but also that they must be adequate and effective, owing to the exceptions established in Article 46(2) of the Convention. 14 In addition, it has been the consistent case law of this Court that an objection to the exercise of the Court’s jurisdiction based on the supposed failure to exhaust domestic remedies must be presented at the proper procedural moment; 15 that is, during the admissibility procedure before the Commission, 16 and the remedies that remained to be exhausted and their effectiveness must be indicated precisely. 25. In keeping with the above, the Court notes that, in the initial petition before the Commission, the criminal proceedings, their result and, consequently, the laws that supported this, formed part of the facts of which the State was made aware. This also meant that the conventionality of the laws applied by the domestic courts was called into question from the time of the said initial petition. Therefore, the State had the procedural burden of presenting its arguments on admissibility based on those facts at the first possible opportunity before the Commission 17 and, in this case, this corresponded to the admissibility stage; all this without prejudice to other violations, strictly related to the same facts, being alleged at a subsequent stage. Thus, even though the State was aware of, and was able to comment on the facts related to the criminal proceedings and the laws that were applied from the moment the initial petition was forwarded to it, it did Cf. Case of Velásquez Rodríguez v. Honduras. Preliminary objections. Judgment of June 26, 1987. Series C No. 1 para. 85, and Case of the National Federation of Maritime and Port Workers (FEMAPOR) v. Peru, supra, para. 25. 13 Cf. Case of Velásquez Rodríguez v. Honduras. Merits. Judgment of July 29, 1988. Series C No. 4, para. 63, and Case of the National Federation of Maritime and Port Workers (FEMAPOR) v. Peru, supra, para. 25. 14 Cf. Case of Velásquez Rodríguez v. Honduras. Preliminary objections, supra, para. 88, and Case of the National Federation of Maritime and Port Workers (FEMAPOR) v. Peru, supra, para. 26. 15 Cf. Case of Herrera Ulloa v. Costa Rica. Preliminary objections, merits, reparations and costs. Judgment of July 2, 2004. Series C No. 107, para. 81, and Case of the National Federation of Maritime and Port Workers (FEMAPOR) v. Peru, supra, para. 26. 16 Cf. Case of Mémoli v. Argentina, supra, para. 50, and Case of the National Federation of Maritime and Port Workers (FEMAPOR) v. Peru, supra, para. 26. 17 8