domestic law to the provisions of the Convention includes the text of the Constitution and all legal provisions of a secondary or regulatory character, in order to ensure the effective practical application of the standards for the protection of human rights. 85 86. The Inter-American Court has also found that access to the case file is a requirement sine qua non of the victim’s procedural intervention in the proceedings in which he is a complainant or an intervenor, according to domestic law. Although the Court has considered it admissible that, in certain cases, the measures taken during the preliminary investigation in criminal proceedings may be kept confidential 86 in order to ensure the effectiveness of the administration of justice, this confidentiality may never be invoked to prevent the victim from accessing the case file in a criminal trial. The State’s authority to avoid the dissemination of the contents of the proceedings, if appropriate, must be guaranteed by the adoption of the necessary measures that are compatible with the exercise of the victims’ procedural rights. 87. Even though Mr. Brewer and his representatives were given access to the case file, the defense was not allowed to obtain photocopies. In the Case of Radilla Pacheco v. Mexico, the Inter-American Court considered that “the refusal to issue copies of the investigation case file to the victims constitute[d] a disproportionate burden against them, incompatible with their right to participate in the preliminary inquiry” and that “States must have mechanisms that are less harmful to the right of access to justice to protect the dissemination of the content of investigations that are underway and the integrity of the case files.” 87 88. In addition, the above-mentioned series of provisional prosecutors and judges and its possible effect on the specific case is also related to the presumed violation of Article 8(2)(f) of the American Convention, owing to the impossibility of presenting pre-trial evidence with regard to Pedro Carmona Estanga and to be present during the examination of Patricia Polea. Indeed, this provision of the Convention establishes that one of the basic guarantees of any person accused of an offense consists in “the right of the defense to examine witnesses present in the court and to obtain the appearance, as witnesses, of experts or other persons who may throw light on the facts.” 88 Thus, this right, as a basic guarantee, is protected during the different stages of the criminal proceedings. 89 89. On this point, it is necessary to distinguish two specific issues in this case. In the first place, the one relating to the pre-trial evidence consisting in the testimony Pedro Carmona Estanga, evidence that was not accepted by the prosecutor based on the argument that he was one of the co-accused in the criminal proceedings, although this would plainly have been essential in order to throw light on the facts. Mr. Brewer’s representatives affirm that the decision not to admit this pre-trial evidence was “arbitrary 85 Cf. Case of Zambrano Vélez et al. v. Ecuador. Monitoring compliance with judgment. Order of the InterAmerican Court of Human Rights of September 21, 2009, forty-ninth considering paragraph, and Case of Radilla Pacheco v. Mexico. Preliminary objections, merits, reparations and costs. Judgment of November 23, 2009. Series C No. 209, para. 247. 86 Cf. Case of Barreto Leiva v. Venezuela. Merits, reparations and costs. Judgment of November 17, 2009. Series C No. 206, paras. 54 and 55. 87 Case of Radilla Pacheco v. Mexico. Preliminary objections, merits, reparations and costs. Judgment of November 23, 2009. Series C No. 209, para. 256. 88 Similarly, Case of Ricardo Canese v. Paraguay. Merits, reparations and costs. Judgment of August 31, 2004. Series C No. 111, para. 164. 89 Case of Mohamed v. Argentina. Preliminary objection, merits, reparations and costs. Judgment of November 23, 2012. Series C No. 255, para. 91. 22