78 tried and convicted the accused and to which the latter has or may have recourse. For a true review of the judgment, in the sense required by the Convention, the higher court must have the jurisdictional authority to take up the particular case in question. It is important to underscore the fact that from first to last instance, a criminal proceeding is a single proceeding in various stages, 114 including the processing of the ordinary challenges filed against the judgment. 160. that: Article 31(1) of the 1969 Vienna Convention on the Law of Treaties provides A treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose. 161. In keeping with the object and purpose of the American Convention, which is effective protection of human rights, 115 the remedy contemplated in Article 8(2)(h) of the Convention must be an effective, ordinary remedy whereby a higher judge or court corrects jurisdictional decisions that are not in keeping with the law. While States have a margin of discretion in regulating the exercise of that remedy, they may not establish restrictions or requirements inimical to the very essence of the right to appeal a judgment. The Court has established that the “formal existence of remedies is not sufficient; these must be effective;” in other words, they must provide results or responses to the end that they were intended to serve. 116 162. Based on the foregoing considerations, the Court will now determine whether the writ of cassation to which Mr. Mauricio Herrera Ulloa had access fit the parameters described above and whether it was, in the final analysis, a remedy regulated by and applied in accordance with the terms of Article 8(2)(h) of the American Convention. 163. The higher court or judge in charge of deciding the remedy filed against a criminal judgment, has a special duty to protect the judicial guarantees and due process to which all parties to the criminal proceeding are entitled, in accordance with the principles governing that proceeding. 164. The possibility of appealing the judgment must be accessible; the kind of complex formalities that would render this right illusory must not be required. 165. Regardless of the label given to the existing remedy to appeal a judgment, what matters is that the remedy guarantees a full review of the decision being challenged. 166. The Inter-American Court of Human Rights concluded the following in this regard: 114 Cf. Case of Castillo Petruzzi et al. Judgment of 30 May 1999. Series C No. 52, para. 161. 115 Cf. Case of Baena-Ricardo et al. Competence. Judgment of November 28, 2003. Series C No. 104, para. 95; Case of Cantos. Preliminary Objections. Judgment of September 7, 2001. Series C No. 85, para. 37; and Case of Constantine et al. Preliminary Objections, supra note 24, para. 86. 116 Cf. Case of Baena-Ricardo et al. Competence, supra note 115, para. 77; Case of Maritza Urrutia, supra note 7, para. 117; and Case of Juan Humberto Sánchez, supra note 20, para. 121.