4. The briefs of the representatives of the victims (hereinafter “the representatives”) of November 8, 2007, March 5, 2008, and February 26, June 8 and October 30, 2009, in which they presented their observations on the status of compliance with the judgment. 5. The communications of the Inter-American Commission on Human Rights (hereinafter “the Commission” or “the Inter-American Commission”) of January 9, 2008, and June 18 and 23, 2009, in which it presented its observations on the status of compliance with the judgment. 6. The note of the Court’s Secretariat of October 14, 2009, in which, on the instructions of the Court in plenary, it requested the State to present information on specific aspects relating to compliance with the judgment, within a non-extendible time frame that expired on November 9, 2009. CONSIDERING THAT: 1. One of the inherent attributes of the jurisdictional functions of the Court is to monitor compliance with its decisions. 2. Peru has been a State Party to the American Convention on Human Rights (hereinafter “the American Convention” or “the Convention”) since July 28, 1978, and accepted the compulsory jurisdiction of the Court on January 21, 1981. 3. As established in Article 67 of the American Convention, the States must comply with the judgments of the Court promptly and fully. 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. 1 4. The obligation to comply with the decisions in the Court’s judgments corresponds to a basic principle of the law on 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. The treaty obligations of the States Parties are binding for all the powers and organs of the State. 2 5. 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 1 Cf. Case of Baena Ricardo et al. Competence. Judgment of November 28, 2003. Series C No. 104, para. 60; Case of the Dos Erres Massacre v. Guatemala. Monitoring compliance with judgment. Order of the InterAmerican Court of Human Rights of July 6, 2011, third considering paragraph, and Case of Montero Aranguren et al. (Retén de Catia) v. Venezuela. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of August 30, 2011, third considering paragraph. 2 Cf. Case of Baena Ricardo et al. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of November 22, 2002, second and third considering paragraphs; Case of the Dos Erres Massacre, supra note 1, fourth considering paragraph, and Case of Montero Aranguren et al., supra note 1, fourth considering paragraph. 2