settlement,” and Article 47.d of the Convention provides that the Commission shall consider inadmissible any petition that is “substantially the same as one previously studied by the Commission or by another international organization.” In the instant case, the parties have not alleged the existence of either of these circumstances, nor can they be deduced from the proceedings. 4. Nature of the allegations 79. The Commission considers that at this stage of the proceeding it is not in order to determine whether or not there has been a violation of the American Convention. To determine admissibility, the Commission must decide whether the facts stated tend to establish a violation of rights, as required by Article 47.b of the American Convention, or whether the petition is "manifestly groundless" or "obviously out of order," as specified in paragraph (c) of this article. 80. The criteria for evaluation of these requirements differ from those used to decide on the merits of a petition. The IACHR must make a prima facie evaluation to determine if the petition states facts that tend to establish a violation of the rights guaranteed by the Convention, rather than establish the existence of a violation of rights. This determination is a preliminary analysis, which does not prejudge the merits of the case. 81. Using a similar criteria to that employed ut supra, it is necessary here to analyze the various facts in this proceeding without further attention to the death sentence of the alleged victim, because its characterization as a possible violation of Article 4.2—if the alleged facts are proved—would be similar to that done in the case of Mr. Raxcacó Reyes, since the circumstances surrounding their trial and death sentences were identical. 82. Concerning the alleged torture of Mr. Ruiz Fuentes by State agents, the Commission has already noted that when facts of torture are denounced it is incumbent on the appropriate judicial authorities to undertake all measures of due diligence to determine the truth. On this point, if the lack of diligence argued by the petitioners is proven, it could constitute a violation of Articles 8.1 and 25 of the American Convention. If a proper investigation confirms the truth of the alleged torture, this would be a violation of Article 5 of the American Convention and of Articles 1, 6, and 8 of the Inter-American Convention to Prevent and Punish Torture. 83. Furthermore, concerning the alleged summary execution of Mr. Ruiz Fuentes, if the petitioners’ allegations are confirmed, it could constitute a violation of Article 4 of the Convention, and if the alleged lack of due diligence or obstruction of justice are proven, it would also be a violation of Articles 8.1 and 25 of the American Convention. 84. Based on the foregoing considerations, the Commission finds that the requirements established in Article 47.b and c of the American Convention have been satisfied because the petitioners’ arguments are not manifestly groundless with regard to the possible violation of the rights guaranteed in Articles 4, 5, 8.1, and 25 of the American Convention in connection with Article 1.1 of the same treaty, and in Articles 1, 6, and 8 of the Inter-American Convention to Prevent and Punish Torture to the detriment of Mr. Hugo Humberto Ruiz Fuentes. VI. CONCLUSION 14