-5State, 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 obligations of the States Parties are binding for all the powers and organs of the State. 8. That 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.4 9. That the States Parties to the American Convention that have accepted the Court’s compulsory jurisdiction must comply with the obligations established by the Court. In this regard, Peru must adopt all necessary measures to comply effectively with the rulings of the Court in the judgment of February 28, 2003, and in the Order of the Court of September 12, 2005 (supra Having seen paragraphs 1 and 3). This obligation to comply with the Court’s decisions includes the State’s duty to report to the Court on the measures adopted to comply with the decisions of the Court in the said judgment, and in this Order. The prompt implementation of the State’s obligation to report to the Court on how each of the aspects ordered by the Court is being fulfilled is essential to assess the status of compliance in the case. 10. That, in the Order of September 12, 2005, the Court, inter alia, required the State to submit, by November 30, 2005, at the latest, a report indicating all the measures adopted to comply with the reparations pending compliance (supra Having seen paragraph 3); specifically, it considered that: a) The State must forward information with regard to the obligation to ‘conduct the corresponding investigations and apply the pertinent punishments to those responsible for failing to abide by the judicial decisions delivered by the Peruvian courts during the applications for protective measures filed by the victims,’ that would allow the Court to determine whether any investigation had been initiated and, if so, the status of this investigation, as well as referring to the matter mentioned by the representatives, that the victims had requested the Public Prosecutor’s Office to open an investigation, but this had been rejected […]; and, b) The State must submit detailed information on the alleged reductions in the pensions of the four victims and the widow of Mr. Gamarra Ferreyra that occurred as of June 2005, and of the administrative-law proceedings alluded 3 Cf. Case of the Constitutional Court. Compliance with judgment, supra note 1, fifth considering paragraph; Case of Ricardo Canese. Compliance with judgment, supra note 1, fifth considering paragraph; and Case of the 19 Tradesmen. Compliance with judgment, supra note 1, fifth considering paragraph. 4 Cf. Case of the Constitutional Court. Compliance with judgment, supra note 1, sixth considering paragraph; Case of Ricardo Canese. Compliance with judgment, supra note 1, sixth considering paragraph; Case of the 19 Tradesmen. Compliance with judgment, supra note 1, sixth considering paragraph.