offense, in order not to punish acts that are not punishable by law.110 106. In this regard, the Convention prohibits arrest or imprisonment by methods that may be legal but, in practice, are unreasonable or disproportionate.111 The Court has established that to comply with the basic requirements to restrict the right to personal liberty, the State must justify and prove, in the specific case, the existence of sufficient indications that would allow for reasonable suspicion of the criminal conduct of the individual and that the detention is strictly necessary;112 consequently, this cannot be based on mere suspicion or personal perceptions that the accused belongs to an illegal group or gang. 107. Furthermore, the Court understands that collective arrest may represent a mechanism to guarantee public security when the State has elements to prove that the actions of each individual arrested conforms to any of the grounds for arrest provided for in its domestic norms in keeping with the Convention. In other words, that there are elements to individualize and separate the conducts of each detainee and, at the same time, there is control by the judicial authority.113 108. Thus the State must ensure that any legal or administrative amendment or reform complies with the State’s obligation to guarantee that arrests do not take place without legal grounds during which the State arrests groups of individuals that the authority supposes may represent a risk or danger to the safety of others, without substantiated evidence that an offense has been committed.114 Consistent with the foregoing, in the cases of Bulacio and Servellón García, the Court established that the so-called razzias are incompatible with respect for the fundamental rights, including the presumption of innocence, and the existence of an arrest warrant – unless flagrante delicto is presumed.115 Consequently, the said norms should not justify mass and arbitrary arrests of groups living on the margins of society. ii. Other legal provisions 109. With regard to the Law on the National Penitentiary System, the Special Regulations for the Operation of the system, and the Prison Administration Manual (supra para. 98), the Court endorses the one-year period stipulated in the agreement for the State to report to the Court on the adoption of the said norms, which commences on notification of this Judgment. 110. The Court notes that, when drafting these norms, the State must take into account the standards on prison conditions established in paragraph 67 of this Judgment and other case law of the Court. The State must also implement effective prevention mechanisms in accordance with paragraph 68 of this Judgment in order to avoid and, if necessary, deal with crisis situations such as fires and other emergencies. 110 Cf. Case of De La Cruz Flores v. Peru. Merits, reparations and costs. Judgment of November 18, 2004. Series C No. 115, paras. 79 to 82, and Case of Yvon Neptune v. Haiti. Merits, reparations and costs. Judgment of May 6, 2008. Series C No. 180, para. 125. 111 Cf. Case of García Asto and Ramírez Rojas. Judgment of November 28, 2005. Series C No. 137, para. 105, and Case of Servellón García et al., supra note 63, para. 90. 112 Cf. Case of López Álvarez, supra note 65 para. 69, and Case of Servellón García et al., supra note 63, para. 90. 113 Cf. Case of Servellón García et al., supra note 63, para. 92. 114 Cf. Case of Servellón García et al., supra note 63, para. 93. 115 Cf. Case of Bulacio v. Argentina. Merits, reparations and costs. Judgment of September 18, 2003. Series C No. 100, para. 137, and Case of Servellón García et al., supra note 63, para. 93. 31