CAT/C/71/D/759/2016 strength in both hands. Some of these injuries were still present at least two years after the incident. The Committee also notes that the State party has provided a different version of the context of his detention, qualifying the offence as damage and injury, and notes the lack of more detailed information from the State party. The Committee considers that the complainant’s allegations concerning the beatings he received during his arrest and transfer and the set of circumstances in which he was held in detention, without medical attention or water, constitute acts conducive to finding a violation of article 1 of the Convention, and for this reason does not consider it necessary to consider separately whether a violation of article 16 also exists. 10.4 The complainant alleges a violation of article 2 of the Convention, in connection with article 1, because the State party failed to comply with its obligation to prevent torture by allowing him to be arrested without a prior court order, without his details having been recorded in the detainee register and without judicial oversight of his detention. The Committee notes that the complainant was arrested without a warrant and without any possibility of communicating with his wife or with an independent lawyer. The Committee recalls its conclusions and recommendations, in which it has urged the State party to take effective measures to ensure that detainees enjoy the benefits of all fundamental safeguards in practice from the outset of their deprivation of liberty, in line with international standards, including, in particular, the right to receive legal assistance without delay, to be informed of the reasons for their arrest and to have their detention registered. 27 In the light of the above circumstances and the lack of information from the State party about these events, the Committee considers that the State party has failed to fulfil its obligation to take effective measures to prevent acts of torture as set out in article 2 (1) of the Convention. 10.5 The Committee also notes the complainant’s argument that article 11 of the Convention was violated because, during his deprivation of liberty, the State party applied neither the Istanbul Protocol nor any other manual compliant with international standards for the prevention, identification and documentation of torture. The Committee also recalls its concluding observations on the seventh periodic report of Mexico, in which it urged the State party to ensure the systematic review of interrogation and arrest procedures, in accordance with article 11.28 In the absence of information from the State party that demonstrates that provision was made for oversight of the conditions of the complainant’s detention, the Committee concludes that there has been a violation of article 11 of the Convention by the State party. 10.6 With regard to articles 12 and 13 of the Convention, the Committee notes the complainant’s allegations that no prompt, immediate and thorough investigation of the acts of torture was carried out by the competent authorities. 10.7 The Committee recalls that article 12 of the Convention requires State parties to ensure that its competent authorities proceed to a prompt and impartial investigation wherever there is reasonable ground to believe that an act of torture has been committed.29 In this regard, the Committee notes that, even though, as recorded in the medical certificates, the complainant had visible injuries on 29 April 2013, a prompt investigation into the alleged facts was not initiated. The State party has argued that an investigation into the offence of injury to the complainant and damage to a vehicle was initiated against various police officers after the case was opened on 29 April 2013, and that, on 27 October 2016, a criminal suit was brought against the police officers named by the complainant, in which the complainant did not take part. The State party also argued that the duty to investigate is an obligation of means and not of result. 10.8 The Committee further recalls that an investigation is not sufficient in itself to demonstrate the State party’s conformity with its obligations under article 12 of the Convention: it also requires that the investigation should be prompt and impartial.30 It recalls that promptness is essential both to ensure that the victim does not continue to be subjected 27 28 29 30 14 CAT/C/MEX/CO/7, para. 15. Ibid., para. 17. Ramírez Martínez et al. v. Mexico, para. 17.7. See, inter alia, the Committee’s decision in Evloev v. Kazakhstan, paras. 9.4 and 9.5. GE.21-13347