352. The Court emphasizes that any violation of Article 7(2) to (7) of the Convention will necessarily entail the violation of Article 7(1) thereof, since the failure to respect the guarantees of the person deprived of liberty implies, in short, a lack of protection of that person’s right to liberty. 488 B.1. Articles 7(1), 7(2), 7(3) and 7(5) of the Convention 353. The Court recalls the principle of liberty of the defendant while his criminal responsibility is being determined. In accordance with this Court’s jurisprudence, pretrial detention is the most severe measure that can be applied to a person accused of a crime, and therefore its application must be exceptional, since it is limited by the principles of legality, presumption of innocence, necessity, and proportionality, which are indispensable in a democratic society. 489 Furthermore, the judicial decision that restricts the personal liberty of a person by means of pretrial detention must be justified and proven, in the specific case, through the existence of sufficient evidence to reasonably assume the criminal conduct of the person and that the detention is strictly necessary. Consequently, it cannot be based on mere suspicion or personal perceptions that the accused belongs to an illegal group or gang. 490 In any case, the deprivation of liberty of the accused must only have the legitimate purpose of ensuring that he or she will not impede the development of the proceedings or evade the action of justice. 491 354. Article 7(2) of the American Convention states that “[n]o one shall be deprived of his physical liberty except for the reasons and under the conditions established beforehand by the constitution of the State Party concerned or by a law established pursuant thereto.” This Court has pointed out that by referring to the Constitution and laws established “therein”, the study of the observance of Article 7(2) of the Convention obliges the States to establish, as specifically as possible and “beforehand,” the “reasons” and “conditions” for the deprivation of physical liberty. If domestic legislation, both in the material and the formal aspects, is not observed when depriving a person of his or her liberty, such deprivation shall be unlawful and contrary to the American Convention. 492 355. With regard to the arbitrariness referred to in Article 7(3) of the Convention, the Court has established that no one shall be subject to arbitrary arrest or imprisonment for reasons and by methods which, although classified as legal, may be considered incompatible with respect for the fundamental rights of the individual because, among other things, they are unreasonable, unpredictable or lacking in proportionality. 493 In this sense, the arbitrariness mentioned in Article 7(3) of the Convention has its own legal content, the analysis of which is only necessary in the case of detentions considered unlawful. 494 However, this means that domestic law, the applicable procedures and the corresponding general principles, expressed or tacit, must also be compatible with the Convention. Thus, the concept of “arbitrariness” is 488 Cf. Case of Chaparro Álvarez and Lapo Iñiguez v. Ecuador, supra, para. 54, and Case of Yarce et al. v. Colombia, supra, para. 138. 489 Cf. Case of Tibi v. Ecuador, Preliminary objections, merits, reparations and costs. Judgment of September 7, 2004. Series C No. 114, para. 106, and Case of Herrera Espinoza et al. v. Ecuador, supra, para. 143. 490 Cf. Case of Pacheco Teruel et al. v. Honduras. Merits, reparations and costs. Judgment of April 27, 2012. Series C No. 241, para. 106, and Case of Herrera Espinoza et al. v. Ecuador, supra, para. 143. 491 Cf. Case of Servellón García et al. v. Honduras. Judgment of September 21, 2006. Series C No. 152, Para. 90, and Case of Herrera Espinoza et al. v. Ecuador, supra, para. 143. 492 Cf. Case of Chaparro Álvarez and Lapo Iñiguez v. Ecuador, supra, para. 57, and Case of Yarce et al. v. Colombia, supra, para. 139. 493 Cf. Case of Gangaram Panday v. Suriname. Merits, reparations and costs. Judgment of January 21, 1994. Series C No. 16, Para. 47, and Case of Yarce et al. v. Colombia, supra, para. 140. 494 Cf. Case of Chaparro Álvarez and Lapo Íñiguez v. Ecuador, supra, para. 96, and Case of Yarce et al. v. Colombia, supra, para. 140. 114