46. The Commission, and the Inter American Court, like other international human rights bodies, has applied the generally recognized principle of international law that international instruments are not retrospective in effect. The Vienna Convention on the law of treaties codifies this principle in Article 28, which provides that: Unless a different intention appears from the treaty or is otherwise established, its provisions do not bind a party in relation to any act or fact which took place or any situation which ceased to exist before the date of the entry into force of the treaty with respect to that party. 47. However, in keeping with international law, the Inter-American human rights system recognizes that States may be liable for violations that originated prior to a State's ratification of a treaty or other international instrument, but continue thereafter.22 48. Having regard for the Petitioners’ submissions, the Commission must determine whether the alleged violations had already been consummated prior to the State's accession to the American Convention (and American Declaration) or are continuing. Based on the record before it, the Commission considers that, while the establishment of the nature reserves and the issue of some of the individual land titles occurred prior to the State’s accession to the Convention, the Petitioners have prima facie demonstrated that the alleged violations were not consummated prior to the State’s accession to the American Convention, but have continued after Suriname’s accession to the American Convention (and American Declaration). Accordingly, the Commission finds that insofar as these events may be of a continuing nature, it has the competence, ratione temporis, to examine the alleged violations of the American Convention. Duplication of procedures, res judicata 49. The State contends that the petition is inadmissible because it is “substantially the same as one previously studied by the Commission or by another international organization”, pursuant to Article 47(d) of the American Convention. The State contends (a) that the subject matter of the petition was previously considered by the CERD, commencing in 2002; and (b) that the Commission declined to uphold this identical submission in the Twelve Saramaka Clans case because the petition in that case pre-dated the proceedings before the CERD. In response, the Petitioners contend that the State made a similar submission in the case of the Twelve Saramaka Clans, which was rejected by the Commission. The State also contests the Commission’s finding in that earlier case, that proceeding before the CERD did not constitute a duplication of proceedings. In response to these submissions, the Commission wishes to point out the following: a) The timing of the petition in the Twelve Saramaka Clans vis a vis the proceedings before CERD was not the basis of the Commission’s rejection of the State’s submission in that matter. b) The Commission found that the proceedings before the CERD had to do with the latter’s review of periodic reports and not with a measure seeking settlement in international proceedings of the subject that was the basis of the petition. c) Consequently, the Commission concluded that the subject of the petition was not pending in another international proceeding for settlement and therefore found no impediment to the admissibility of the petition lodged by the petitioners. 50. The Commission finds that its analysis in the Twelve Saramaka Clans appliesmutatis mutandis with equal rigor to the petition under consideration, and therefore dismisses the I/A Court H.R., Case of Blake. Preliminary Objections. Judgment of July 2, 1996. Series C No. 27; I/A Court H.R., Case of Cantos. Preliminary Objections. Judgment of September 7, 2001. Series C No. 85; I/A Court H.R.,Case of Alfonso Martín del Campo-Dodd. Preliminary Objections. Judgment of September 3, 2004. Series C No. 113; I/A Court H.R., Case of Almonacid-Arellano et al. Preliminary Objections, Merits, Reparations and Costs. Judgment of September 26, 2006. Series C No. 154; IACHR Report N° 74/90 Case 9850, Hector Geronimo Lopez Aurelli, Argentina, 4 October 1990. 22 10