111. From the prohibition of using any form of coercion to obtain the confession of an accused established in article 8.3 of the Convention, it follows that “annulment of procedural documents resulting from torture or cruel treatment is an effective measure to halt the consequences of a violation of judicial guarantees.”116 Said measure not only includes confessions obtained through torture or cruel treatment, but also “extends to any form of duress” that can interfere with the “spontaneous expression of a person’s will,” which “necessarily implies the obligation to exclude that evidence from the judicial proceeding.” 117 This obligation, according to the Court, refers not only to evidence obtained directly by coercion, “but also to evidence derived from such action.”118 The purpose of the exclusionary rule is precisely to discourage and prevent the use of principles that are unlawful and contrary to the Convention such as torture or other cruel treatment, and thus, compliance with such a rule is essential. 112. Taking the above into account, the Commission will analyze whether the preliminary statement made by Mr. Montesinos under duress—described in this report as constituting at the very least cruel, inhuman, and degrading treatment—was used during the proceedings or whether such statement was duly excluded. 113. The Commission notes first of all that Mr. Montesinos’ preliminary statement made on June 25, 1992, in which he confessed to having weapons in his home left in his care him by someone accused of drug trafficking, was included in the Operación Ciclón police report. In this report the official investigator establishes Mr. Montesinos’ involvement in an international drug trafficking gang based on the content of his preliminary statement. Based on what had been in established in this police report, three orders were issued to initiate proceedings for the crimes of: (i) Illicit enrichment; (ii) conversion and transfer of assets; and (iii) engaging in front operations. 114. The Commission notes that the authorities who decided to continue the process did so not only taking into account his preliminary statement that was made under duress and—as indicated below— without professional legal counsel, but rather giving it preeminent importance. The court file does not show that authorities who heard the case conducted any assessment of reported coercion or the subsequent need to exclude such confessions. The Commission considers that this decision is independent of the final outcome of the proceedings. 115. In light of the above, the Commission considers that the State not only violated the right to humane treatment as described previously, but also the right set forth under Article 8(3) of the American Convention in connection with Article 1(1) thereof, to the detriment of Mario Montesinos Mejía. 2. Right to legal representation 116. The Court has held this right must be exercised from the moment a person is accused of perpetrating or participating in an unlawful action and only ends when the proceeding concludes.119 In the case of Chaparro Álvarez and Lapo Íñiguez v. Ecuador, the Court considered that the State violated the victims’ right to legal representation given that the victims’ attorneys were unable to be present when a procedure that was key in the victims’ trial for drug trafficking took place.120 116 I/A Court H.R. Case of Cabrera García and Montiel Flores v. Mexico. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 26, 2010 Series C No. 220, paragraph 166. I/A Court H.R. Case of García Cruz and Sánchez Silvestre v. Mexico. Merits, Reparations, and Costs. Judgment of November 26, 2013. Series C No. 273, paragraph 58, see, in particular, footnote 73. 117 I/A Court H.R. Case of Cabrera García and Montiel Flores v. Mexico. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 26, 2010 Series C No. 220, paragraph 166. 118 I/A Court H.R. Case of Cabrera García and Montiel Flores v. Mexico. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 26, 2010 Series C No. 220, paragraph 167. 119 I/A Court H.R. Case of Cabrera García and Montiel Flores v. Mexico. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 26, 2010 Series C No. 220, paragraph 154; and Case of Barreto Leiva v. Venezuela. Merits, Reparations, and Costs. Judgment of November 17, 2009. Series C No. 206, paragraph 29. 120 I/A Court H.R. Case of Chaparro Álvarez and Lapo Íñiguez. v. Ecuador. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 21, 2007. Series C No. 170, paragraph 154. 21