9 40. For the purposes of admissibility, the Commission must decide whether the facts alleged tend to establish a violation of rights, pursuant to Article 47.b of the American Convention, or whether the petition is “manifestly groundless” or “obviously out of order,” pursuant to Article 47.c. The criterion for evaluating these requirements is different from the one used to decide on the petition’s merits; the Commission must carry out a prima facie evaluation to determine whether the petition establishes grounds for the possible or potential violation of a right guaranteed under the American Convention, but not to establish whether an infringement of rights has occurred. This determination constitutes a preliminary analysis that does not entail a prejudgment on the merits of the case.5 41. Neither the American Convention nor the Rules of Procedure of the IACHR require the petitioners to identify the specific rights allegedly violated by the State in the case brought before the Commission, although the petitioners may do so. However, it is incumbent on the Commission, in keeping with the jurisprudence of the system, to determine in its admissibility reports which provision of the relevant inter-American instruments is applicable and could be deemed to have been violated if the alleged facts are proven by means of sufficient evidence and legal arguments. 42. The Commission notes that the characterization of the alleged facts is in dispute. The Argentinian State holds that in the instant case the formula of the “fourth-instance” is applicable and that the petition does not state facts that tend to constitute a violation of a right guaranteed by the American Convention. For their part, the petitioners hold that they are not proposing a review of the judgment that ordered the dismissal of the proceedings relating to the presumed victim, but rather violations of human rights. 43. The basic premise of the “fourth-instance” formula is that “the Commission cannot review the judgments issued by the domestic courts acting within their competence and with due judicial guarantees, unless it considers that a possible violation of a right protected by the American Convention is involved.6” In this regard, the IACHR has established that it is competent “to declare a petition admissible and rule on its merits when it portrays a claim that a domestic legal decision constitutes a disregard of due process or if it appears to violate any other right guaranteed by the Convention.”7 The Commission recalls that it has admitted petitions when it is inferred prima facie from the allegations of the parties that the judgments or procedures followed could have been arbitrary8 or imply a possible arbitrary unequal treatment or possible discrimination.9 44. In view of the foregoing, given the elements of fact and law introduced by the parties and the nature of the matter brought before it, the IACHR finds that in the instant case it must be established that the petitioners’ allegations related to the presumed violation of the right to guarantees and judicial 5 IACHR, Report No. 4/12, Petition 4115-02, Admissibility, Ricardo Javier Kaplún and family, Argentina, March 19, 2012, par. 36. 6 IACHR, Report No. 8/98, Case 11.671, Inadmissibility, Carlos García Saccone, Argentina, March 2, 1998, par. 53 and Report No. 2/05, Petition 11.618, Admissibility, Carlos Alberto Mohamed, Argentina, February 22, 2005, par. 32. 7 IACHR, Report No. 105, 99, Case 10.194, Admissibility and Merits, Narciso Palacios, Argentina, September 29, 1999, 8 IACHR, Report No 62/12, Petition 1471-05, Admissibility, Yenina Esther Martínez Esquiava, March 20, 2012, par. 48. par. 45. 9 IACHR, Report No. 42/08, Case 12.502, Admissibility, Karen Atala and daughters, Chile, July 23, 2008, par. 63 and Report No. 13/12, Petition 1064-05, Admissibility, Luis Fernando Guevara Díaz, Costa Rica, March 20, 2012, par. 41.