a) there are substantive assumptions that there was an unlawful act and that the accused is connected to that act; b) the measure complies with the four elements of the “test of proportionality”; in other words, the purpose of the measure must be legitimate (compatible with the Convention), 68 it is appropriate to comply with the end sought, necessary and strictly proportionate 69 and c) the decision imposing such a measure must contain an adequate rationale to permit an assessment as to whether it meets the aforementioned conditions. 70 98. In view of the above, the Court recalls that these considerations on the elements that the authorities must take into account when restricting the personal liberty of an individual being investigated for a crime must be contemplated in a State’s legal order and must also be applied effectively and in good faith by the operators of justice. 99. There follows details on each of the aforementioned elements. a) Substantive assumptions that there was an unlawful act and that the accused is connected to that act 100. As to the first point, the Court has indicated that, in order to meet the requisites necessary to restrict the right to personal liberty with a precautionary measure, such as pre-trial detention, there must exist sufficient evidence that would allow a reasonable assumption that an unlawful act occurred and that the person being tried participated in it. 71 101. On this point, it must be stressed that this assumption is not, per se, a legitimate purpose to order a precautionary measure that restricts liberty nor is it an element susceptible of undermining the right to the presumption of innocence (Article 8(2) of the Convention). On the contrary, in the domestic law of various countries of the region and in the practice of international courts, it is a fundamental assumption that must always be present when restrictions to liberty are imposed when the accused is subject to a criminal proceeding. That basic assumption is in addition to the other requisites related to a legitimate purpose: suitability, necessity and proportionality, as well as the need for a justification of the judicial decision that ordered the restriction of liberty. 72 102. The foregoing should be understood by considering that, in principle and in general terms, this decision should not have any effect on the responsibility of the accused, since it should be made by a judge or judicial authority other than that which makes the final determination on the merits. 73 103. With respect to those assumptions, the Court has held that the suspicion or the sufficient evidence that allows the reasonable assumption that the person subjected to the proceedings has participated in the unlawful act being investigated must be well-founded and refer to specific acts; in other words, not on mere conjectures or abstract intuitions. Thus, the State must not detain and then investigate. 74 Cf. Case of Servellón García et al. v. Honduras. Preliminary Objection, Merits, Reparations and Costs. Judgment of September 21, 2006. Series C No. 152, para. 89 and Case of Habbal et al. v. Argentina, supra, para. 64. 68 Cf. Case of Palamara Iribarne v. Chile. Merits, Reparations and Costs. Judgment of November 22, 2005. Series C No. 135, para. 197 and Case of Habbal et al. v. Argentina, supra, para. 64. 69 70 Cf. Case of García Asto and Ramírez Rojas v. Peru. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 25, 2005. Series C No. 137, para. 128 and Case of Habbal et al. v. Argentina, supra, para. 64. Cf. Case of Servellón García et al. v. Honduras, supra, para. 90; Case of Chaparro Álvarez and Lapo Íñiguez v. Ecuador, supra, paras. 101 and 103 and Case of Hernández v. Argentina. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 22, 2019. Series C No. 395, para. 104. 71 Cf. Case of Romero Feris v. Argentina. Merits, Reparations and Costs. Judgment of October 15, 2019. Series C No. 391, para. 93. 72 Cf. Mutatis mutandis, Case of Herrera Ulloa v. Costa Rica. Preliminary Objections, Merits, Reparations and Costs. Judgment of July 2, 2004. Series C No. 107, para. 174 and Case of Romero Feris v. Argentina, supra, para. 95. 73 74 Cf. Case of Norín Catrimán et al. (Leaders, Members and Activist of the Mapuche Indigenous People) v. Chile. Merits, Reparations and Costs. Judgment of May 29, 2014. Series C No. 279, para. 311; Case of Chaparro Álvarez and Lapo Íñiguez v. Ecuador, para. 103 and Case of González et al. v. Venezuela. Merits and Reparations. Judgment of September 20, 2021. Series C No. 436, footnote 110. 25