252. The State also argued that transitory provision I of Law 8503 constituted a special procedural instrument that only required for its filing and processing that the person who considered himself affected by the manner in which the cassation appeal was resolved, and that his right to appeal the judgment had been violated, to file a petition for review invoking such reason, without further formality, even being able to file more than one motion for review, as long as the claim was supported by new allegations. In this regard, it explained that the special review regulated in transitory provision I is not a rigid or exceptional procedure. These characteristics of the special review were maintained in Law 8937 of 2010, through which alleged victims were granted a legal period of 18 months, and in addition, 6 months from its entry into force, to claim the violation of Article 8(2)(h) and present all the arguments related to such situation through the procedural mechanism of review of the judgment. 253. In addition, the State pointed out that Law No. 8837 of 2010 essentially complements and expands the scope of Law No. 8503, and that transitory provision III of Law 8837 constituted a procedural mechanism that provided an effective means for those who considered that their right to appeal the judgment had been violated prior to its enactment to claim and demonstrate such a situation. With respect to the possibility of filing a single motion for review within the first six months of the enactment of Law 8837, it pointed out that this did not imply any restriction of the effective protection of the right to appeal the judgment, since it would not be feasible to review ex officio all final convictions prior to said law, and neither would the generic argument of the “non-existence of the appeal” prior to its enactment be sufficient. 254. Furthermore, the State emphasized that the appeals system provided for in the Costa Rican criminal procedure system reflects the best standards in the Latin American region. 350 According to the State, to consider that Costa Rica's criminal appeals system is contrary to the Convention would imply disqualifying one of the procedural systems in the region that has granted the most defense guarantees to the accused. This would also imply a setback to the processes of democratization of criminal justice in the Latin American region, and a return to inquisitorial systems of hierarchical control in the decisions of the sentencing judges, as well as a weakening of the oral trial as the central phase of the entire procedure. Finally, the State referred in detail to the situation of each group of alleged victims. B. Considerations of the Court 255. In its constant case law, the Court has referred to the scope and content of Article 8(2)(h) of the Convention, as well as to the standards that should be observed to ensure the right to appeal the judgment before a higher judge or court. The Court considers that the right to appeal the judgment is an essential guarantee that “must be respected as part of due process of law, so that a party may turn to a higher court for review of a judgment that was unfavorable to that party’s interests […].” 351 Bearing in mind that judicial guarantees seek to ensure that anyone involved in a judicial proceeding is not subject to arbitrary decisions, the Court interprets that the right to appeal a judgment cannot be effective unless it is guaranteed The State analyzed CCP of 1973, the CCP of 1996, the reform of Law 8503 of 2006 and the reform of Law 8837, comparing their norms with the codes of criminal procedure of Mexico, Chile and Argentina (merits file, folios 1158 to 1178). 351 Cf. Case of Herrera Ulloa v. Costa Rica, supra, para. 158, and Case of Zegarra Marín v. Peru. Preliminary objections, merits, reparations and costs. Judgment of February 15, 2017. Series C No. 331, para. 170. 350 79