62 a. 224. The violation of the guarantees of due process and the principle of legality, 215 recognized in articles 8 and 9 of the American Convention Article 8 of the American Convention provides that: 1. Every person has the right to a hearing, with due guarantees and within a reasonable time, by a competent, independent, and impartial tribunal, previously established by law, in the substantiation of any accusation of a criminal nature made against him or for the determination of his rights and obligations of a civil, labor, fiscal, or any other nature. 2. Every person accused of a criminal offense has the right to be presumed innocent so long as his guilt has not been proven according to law. During the proceedings, every person is entitled, with full equality, to the following minimum guarantees: (…) f. 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; (…) h. the right to appeal the judgment to a higher court. (…) 4. An accused person acquitted by a nonappealable judgment shall not be subjected to a new trial for the same cause. (…) 225. Article 1(1) of the Convention reads as follows: The States Parties to this Convention undertake to respect the rights and freedoms recognized herein and to ensure to all persons subject to their jurisdiction the free and full exercise of those rights and freedoms, without any discrimination for reasons of race, color, sex, language, religion, political or other opinion, national or social origin, economic status, birth, or any other social condition. 226. The petitioners have alleged numerous violations of their procedural rights and guarantees under articles 8 and 9 of the American Convention. Of those allegations, the Commission believes that certain points are of particular relevance: i) the convictions in light of the principle of individual criminal responsibility and the presumption of innocence; ii) the right of defense and the use of anonymous witnesses; iii) the right to appeal a ruling; iv) the right to be tried by a competent, independent and impartial tribunal, and v) the double jeopardy rule. 227. The petitioners did present other arguments, such as: (i) the alleged violation of the presumption of innocence, and the admission and weighing of evidence of guilt and exculpatory evidence, and their application to the criminal cases against Mapuche indigenous persons; (ii) the failure to observe the rights to time and means to prepare one’s defense and to question and call witnesses, recognized in articles 8(2)(c) and 8(2)(f) of the American Convention, in the Angol oral criminal trial court’s criminal prosecution and conviction of Juan Patricio Marileo Saravia, Florencio Jaime Marileo Saravia, Patricia Roxana Troncoso Robles, José Benicio Huenchunao Mariñán and Juan Ciríaco Millacheo Licán, inasmuch as the testimony that the Public Prosecutor’s Office introduced against them at trial was different from the evidence provided to the defense attorneys during the investigative phase of the case and that was used to build their defense; (iii) the failure to observe the rule prohibiting retroactive application of criminal law, recognized in Article 9 of the Convention, to the detriment of petitioners Pascual Pichún and Aniceto Norín, inasmuch as the use of anonymous witnesses during the trial phase of the proceedings meant that a more restrictive criminal procedure law was being applied retroactively to their case; (iv) the failure to respect the right of equality of arms and to summon witnesses, to the detriment of petitioners Juan Patricio Marileo Saravia, Florencio Jaime Marileo Saravia, Patricia Roxana Troncoso Robles, José Benicio Huenchunao Mariñán and Juan Ciríaco Millacheo Licán, 215 Transcribed earlier in this report.