reasonable limits. Whenever it appears that the pre-trial detention does not meet these conditions, the release of the detainee should be ordered, without prejudice to the continuation of the respective proceedings.328 312. Pursuant to the above, it is not sufficient that the pre-trial detention is legal; it is essential that it is not arbitrary, which means that the law and its application must respect the following requirements: a) Purpose compatible with the Convention: the purpose of measures that deprive or restrict liberty must be compatible with the Convention (supra para. 311.a). The Court has indicated that “the deprivation of liberty of the accused cannot be based on general or special preventive objectives that can be attributed to the punishment, but can only be based […] on a legitimate objective, namely: to ensure that the accused will not obstruct the implementation of the proceedings or evade the action of justice.”329 Thus, the Court has indicated repeatedly that the personal characteristics of the supposed perpetrator and the seriousness of the offense he is accused of are not, in themselves, sufficient justification for pre-trial detention.330 It has also stressed that risks to the proceedings cannot be presumed, but must be verified in each case, based on the objective and precise circumstances of the specific case.331 b) Suitability: the measures adopted must be suitable to achieve the objective sought.332 c) Necessity: they must be necessary; in other words, they must be absolutely essential to achieve the objective sought and there is no less onerous measure as regards the right affected among all those that are equally suitable to achieve this objective.333 Thus, even when the aspect relating to sufficient evidence that allows it to be supposed that the accused has taken part in the illegal act has been determined (supra para. 311.b), the deprivation of liberty must be strictly necessary to ensure that the accused will not obstruct the said procedural objectives.334 d) Proportionality: they must be strictly proportionate, so that the sacrifice inherent in the restriction of the right to liberty is not exaggerated or disproportionate in relation to the advantages obtained by this restriction and the achievement of the objective sought.335 e) Any restriction of liberty that does not contain sufficient justification that allows an assessment of whether it is in keeping with the above conditions will be arbitrary and, therefore, violate Article 7(3) of the Convention.336 Thus, in order to respect the presumption of innocence when ordering precautionary measures that restrict liberty, in 328 Cf. Case of Bayarri v. Argentina, para. 76. 329 Cf. Case of Suárez Rosero v. Ecuador. Merits, para. 77, and Case of J. v. Peru, para. 157. 330 Cf. Case of López Álvarez v. Honduras. Merits, reparations and costs. Judgment of February 1, 2006. Series C No. 141, para. 69, and Case of J. v. Peru, para. 159. 331 Cf. Case of Barreto Leiva v. Venezuela, para. 115, and Case of J. v. Peru, para.159. 332 Cf. Case of Chaparro Álvarez and Lapo Íñiguez. v. Ecuador, para. 93. 333 Cf. Case of Chaparro Álvarez and Lapo Íñiguez. v. Ecuador, para. 93. 334 Case of Chaparro Álvarez and Lapo Íñiguez. v. Ecuador, para. 103, and Case of Barreto Leiva v. Venezuela, para. 111. 335 Cf. Case of Chaparro Álvarez and Lapo Íñiguez. v. Ecuador, para. 93. 336 Cf. Case of García Asto and Ramírez Rojas v. Peru, para. 128, and Case of J. v. Peru, para.158. 111