64. Article 7(5), in turn, establishes that a detained person must be tried “within a reasonable time” or “released” even if the trial is ongoing. The same article notes that “release may be subject to guarantees to assure his appearance for trial.” This article indicates that deprivation of liberty measures during a criminal trial are compatible with the Convention as long as they have a precautionary purpose, that is, they are a means of eliminating procedural risks; the article specifically refers to the risk of not appearing at trial. 34 65. Regarding the above, it must be emphasized that preventive detention constitutes the most severe measure that can be taken against an accused person, and for that reason it should be the exception: the norm should be liberty for a person on trial while their criminal responsibility is being determined. 35 One of the principles that limits preventive detention is the presumption of innocence, contained in Article 8(2), according to which a person is considered innocent until proven guilty. It follows from this guarantee that the elements proving the existence of legitimate goals of preventive deprivation of liberty are not presumed either, but rather that the judge must base their decision on true and objective circumstances of the specific case. The burden of proof is on the criminal authorities and not on the accused, who should also have the opportunity to exercise the right to a hearing and to be duly assisted by a lawyer. 36 Thus, the Court has held that the personal characteristics of the alleged perpetrator and the gravity of the crime are not in themselves sufficient justification for preventive detention. 37 66. Article 7(5) of the Convention imposes time limits on the length of preventive detention in relation to the length of the trial, indicating that the trial can continue with the accused not in detention. The Court has held that “even when there are reasons for keeping a person in preventive detention, Article 7(5) guarantees that he will be released if the detention period has exceeded a reasonable time.” 38 67. The above makes clear that in some respects, the judicial guarantees set forth in Article 8 of the Convention can be understood as closely related to the right to personal liberty. Thus, for the purposes of this case, it is relevant to point out that since preventive detention is a precautionary rather than a punitive measure, 39 depriving a person of their liberty beyond a reasonable time to achieve the purposes that justify their detention against which he must defend himself and, consequently, the judicial control is illusory.” Case of Yvon Neptune v. Haiti. Merits, Reparations, and Costs. Judgment of May 6, 2008. Series C No. 180, para. 105 and Case of Women Victims of Sexual Torture in Atenco v. Mexico, para. 246. 34 Cf. Case of Romero Feris v. Argentina, para. 100. 35 Cf. Case of López Álvarez v. Honduras. Merits, Reparations, and Costs. Judgment of February 1, 2006. Series C No. 141, para. 67, and Case of Jenkins v. Argentina, para 72. . 36 Cf. Case of Amrhein et al. v. Costa Rica. Preliminary Objections, Merits, Reparations, and Costs. Judgment of April 25, 2018. Series C No. 354, para. 357, and Case of Romero Feris v. Argentina, para. 101. 37 Cf. Caso Bayarri v. Argentina. Preliminary Objection, Merits, Reparations, and Costs. Judgment of October 30, 2008. Series C No. 187, para. 74; Case of J. v. Peru. Preliminary Objection, Merits, Reparations, and Costs. Judgment of November 27, 2013. Series C No. 275, para. 159, and Case of Romero Feris v. Argentina, para. 101. 38 Cf. Case of Bayarri v. Argentina, para. 74, and Case of Jenkins v. Argentina, para. 84. Cf. Case of Pollo Rivera et al. v. Peru. Merits, Reparations, and Costs. Judgment of October 21, 2016. Series C No. 319, para. 122, and Case of Romero Feris v. Argentina, para. 97. 39 16