6 ‘Any of the requirements indicated in Article 46 has not been met.’ 23. The Commission analyzed the Government’s note during its 78th Session and agreed to confirm its decision to submit the case to the Court. III 24. The Court has jurisdiction to hear the instant case. Peru has been a State Party to the Convention since July 28, 1978. It accepted the contentious jurisdiction of the Court, to which Article 62 of the Convention refers, on January 21, 1981. IV 25. The Court will now examine the preliminary objections interposed by the Government. 26. In its first objection, the Government contends that, pursuant to Article 46, paragraph 1 (b) of the American Convention, one of the requirements for admissibility of a petition by the Commission is that it be lodged within a period of six months from the date on which the party alleging violation of his rights was notified of the final judgment of the domestic courts. If this requirement were not met, the Commission would lack jurisdiction to pursue the case. 27. In the instant case, the petition was filed with the Inter-American Commission on September 1, 1987, according to the Peruvian Government, and on August 31 of that year, according to the Commission’s memorial. This one-day discrepancy in the assertions of each of the parties is legally irrelevant to the resolution of the instant case. The Court does not deem it necessary, therefore, to address this issue. 28. The Government contends in its preliminary objections and reiterated at the hearing of December 6, 1991, that the domestic remedies interposed by the petitioners were exhausted when they received notice of the judgment of the Court of Constitutional Guarantees through its publication in the Official Gazette, that is, on January 14, 1987. The Government adds that under Article 46 of Law N° 23385, which governs the activities of that tribunal, a judgment rendered by it has the effect of exhausting domestic remedies. The foregoing assertion by the Peruvian Government is not consistent with its prior statement to the Commission, contained in its note of September 29, 1989 (supra 18). 29. It follows from the above that on September 29, 1989, Peru contended that domestic remedies had not been exhausted, but that a year later, on September 24, 1990, it asserted the contrary to the Commission, as it now does to the Court. International practice indicates that when a party in a case adopts a position that is either beneficial to it or detrimental to the other party, the principle of estoppel prevents it from subsequently assuming the contrary position. Here the rule of non concedit venire contra factum proprium applies. It could be argued in this case that the proceedings before the Special Military Tribunal do not amount to a real remedy or that that tribunal cannot be deemed to be a court of law. Here neither of these assertions would be relevant. What is