comply with the judgment of the Court in any case to which they are parties.” To this end, the State must ensure that the measures ordered by the Court in its decisions are implemented at the domestic level.2 3. 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, a State must comply with its 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-based obligations of the States Parties are binding on 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 Court’s decisions. These obligations must 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 pay Mr. Vélez Loor the amount established for specialized medical attention and psychological treatment, as well as for medicines and other future related expenses (twelfth operative paragraph of the Judgment) 5. The State advised that it had paid the sum of US$7,500.00 (seven thousand five hundred United States dollars) to Mr. Vélez Loor through the Embassy of Panama in the Republic of Ecuador “for specialized medical attention and psychological treatment, as well as for medicines and other future related expenses.” 6. The representatives confirmed that, on June 10, 2011, the State had delivered a check for US$7,500.00 (seven thousand five hundred United States dollars) to Mr. Vélez Loor, thus complying with the provision established by the Court in its Judgment. Cf. Case of Baena Ricardo et al. Jurisdiction. Judgment of November 28, 2003. Series C No. 104, para. 60, and Case of Salvador Chiriboga v. Ecuador. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of October 24, 2012, second considering paragraph. 2 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 Albán Cornejo v. Ecuador. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of February 5, 2013, fifth considering paragraph. 3 Cf. Case of Castillo Petruzzi et al. v. Peru. Monitoring compliance with judgment. Order of the InterAmerican Court of Human Rights de November 17, 1999, third considering paragraph, and Case of Albán Cornejo v. Ecuador. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of February 5, 2013, fifth considering paragraph. 4 Cf. Case of Ivcher Bronstein v. Peru. Jurisdiction. Judgment of September 24, 1999, Series C No. 54, para. 37, and Case of Barrios Altos v. Peru. Monitoring compliance with judgment. Order of the Inter-American Court of Human Rights of September 7, 2012, fifth considering paragraph. 5 3