attestation by means of the right to challenge evidence that may be biased (derecho de tacha) which may eventually be used against it. 569 405. The State also indicated that, “in the practice, police officials are summoned to hearings and attend them, and this provides guarantees for the right of the persons accused of the crime of terrorism to be able to defend themselves. In this regard, it can be affirmed that the prohibition contained in the legal norm has been overcome in the practice.” The State mentioned several cases in which the police who had taken part in the elaboration of the police attestation had appeared to testify. Similarly, the deponent for information purposes, Federico Javier Llaque Moya, indicated in this regard that: Those who intervened in the attestation have appeared as witnesses in numerous proceedings; their testimony is assessed during the judicial investigation stage by the criminal judge and then subjected to cross-examination in the trial by the Criminal Chamber. To date, this practice has been used so as not to obstruct the right of defense of the person who considers the appearance of such witnesses necessary. 570 406. The case file before the Court also contains a decision of the National Criminal Chamber in which police agents appeared who had taken part, for example, in the operations of the search and the arrest of the accused. 571 407. This Court recalls that it has established that not only the elimination or enactment of norms under domestic law guarantees the rights contained in the American Convention, pursuant to the obligation contained in Article 2 of this instrument. In addition, the implementation of State practices resulting in the effective observance of the rights and freedoms recognized therein is also required. Consequently, the existence of a norm does not, in itself, guarantee that its application is appropriate. The application of the norms or their interpretation as jurisdictional practices and an expression of the legal order must be adapted to the objective sought by Article 2 of the Convention. In other words, the Court underscores that judges and organs for the administration of justice at all levels are obliged to exercise ex officio “control of the conformity” of domestic norms with the American Convention; evidently, within the framework of their respective competences and the corresponding procedural regulations. In this task, they must take into account not only the international treaty concerned, but also how it has been interpreted by the Inter-American Court, ultimate interpreter of the American Convention. 572 408. Based on the above, the Court considers that it is not necessary to order the reform of Article 13(c) of Decree-Law No. 25,475, in the understanding that, according to the information provided to the case file, judicial practice has allowed the questioning of officials who took part in the elaboration of the police attestation in specific cases. D) Obligation to respect the guarantees of due process in the criminal proceedings opened against Ms. J. 409. The Commission asked the Court to order the State “[t]o annul any expression of the State’s punitive powers against J., in which the procedural defects persist that were evident in the trial held in 1992 and 1993 and that gave rise to the violations of the American Convention. Specifically, the 569 Cf. Judgment of the Constitutional Court of January 3, 2003, File No. 010-2002-AI/TCLIMA, conclusions 147 to 159 (merits report, folios 1573 to 1577). 570 Testimony of Federico Javier Llaque Moya during the public hearing held in this case. 571 Cf. Judgment of the National Criminal Chamber of May 25, 2006 (file of annexes to the answering brief, annex 61, folios 4166 to 4168). 572 Cf. Case of Almonacid Arellano et al. v. Chile, supra, para. 124, and Case of Castañeda Gutman v. Mexico. Monitoring compliance with judgment. Order of the Court of August 28, 2013, considering paragraph 23. 119