CONSIDERING THAT: 1. One of the inherent attributes of the jurisdictional functions of the Court is to monitor compliance with its decisions. 2. As established in Article 67 of the American Convention, the judgments of the Court must be complied with fully and promptly by the State. In addition, Article 68(1) of the American Convention stipulates that “[t]he States Parties to the Convention undertake to comply with the judgment of the Court in any case to which they are parties.” To this end, the State must ensure implementation at the national level of the Court’s decisions in its judgments.2 3. The obligation to comply with the decisions in the Court’s judgments corresponds to a basic principle of the law of the international responsibility of the State, supported by international case law, according to which, States must comply with their international treaty obligations in good faith (pacta sunt servanda) and, as this Court has already indicated and as established in Article 27 of the 1969 Vienna Convention on the Law of Treaties, a party may not invoke the provisions of its internal law as justification for its failure to perform a treaty.3 The treaty obligations of the States Parties are binding for all the powers and organs of the State.4 4. The States Parties to the Convention must ensure compliance with its provisions and their inherent effects (effet utile) within their respective domestic legal systems. This principle is applicable not only with regard to the substantive norms of human rights treaties (that is, those which contain provisions concerning the protected rights), but also with regard to procedural norms, such as those referring to compliance with the decisions of the Court. These obligations shall be interpreted and applied so that the protected guarantee is truly practical and effective, bearing in mind the special nature of human rights treaties. 5 a) Obligation to continue effectively and with the greatest diligence the investigations it has commenced, as well as initiate any others necessary in order to identify, prosecute and punish, as appropriate, all those responsible for the forced disappearances of Gregoria Herminia Contreras, Serapio Cristian Contreras, Julia Inés Contreras, Ana Julia Mejía Ramírez, Carmelina 2 Cf. Case of Baena Ricardo et al. v. Panama. Competence. Judgment of November 28, 2003. Series C No. 104, para. 60, and Case of Gelman v. Uruguay. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of March 20, 2013, third considering paragraph. 3 Cf. International responsibility for the Promulgation and Enforcement of Laws in Violation of the Convention (Arts. 1 and 2 American Convention on Human Rights). Advisory Opinion OC-14/94 of December 9, 1994. Series A No. 14, para. 35, and Case of Vélez Loor v. Panama. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of February 13, 2013, third considering paragraph. 4 Cf. Case of Castillo Petruzzi et al. v. Peru. Monitoring compliance with judgment. Order of the InterAmerican Court of Human Rights of November 17, 1999, third considering paragraph, and Case of Vélez Loor v. Panama. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of February 13, 2013, third considering paragraph. 5 Cf. Case of Ivcher Bronstein vs. Peru. Competence. Judgment of September 24, 1999, Series C No. 54, para. 37, and Case of Vélez Loor v. Panama. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of February 13, 2013, fourth considering paragraph. 3