B.2. Lack of due diligence in the criminal investigations 181. The Court must now analyze whether the State conducted the criminal investigations with due diligence and within a reasonable time, and whether these investigations have constituted effective remedies to ensure the right of access to justice and to know the truth of the family members. To this end, the Court may examine the respective domestic proceedings. 298 182. The Court underscores that, for an investigation of an enforced disappearance to be conducted effectively and with due diligence, 299 all the necessary means must be used to promptly take those measures and make those inquiries that are essential and appropriate in order to clarify the fate of the victims and to identify those responsible for their enforced disappearance. 300 To this end, the State must provide the pertinent authorities with the logistic and scientific resources required to gather and process the evidence and, in particular, the power to access documentation and information that is relevant to investigate the facts denounced and to obtain indications or evidence of the victims’ whereabouts. 301 183. Since three different stages can be distinguished in the investigations into the enforced disappearance of Jeremías Osorio Rivera, which culminated in the acquittal of the only person prosecuted, the Court will now analyze: (i) the first investigation conducted in the ordinary jurisdiction between May 1991 and July 1992; (ii) the investigation conducted by the Third Permanent Military Court of Lima from July 1992 to October 1996, and (iii) the new investigation before the special jurisdiction from 2004 to 2013. i. First criminal investigation in the ordinary jurisdiction 184. The first investigation was opened based on the criminal complaint filed by Porfirio Osorio Rivera, the presumed victim’s brother, on May 9, 1991 (supra para. 77), and it was only open for one year because the Investigating Court disqualified itself from hearing the case in favor of the military jurisdiction (supra para. 84). During this first investigation, the preliminary statement of the accused, the statement of the complainant, and graphology and dactylography appraisals of the record of release of May 1, 1991, were received (supra paras. 79 to 81). However, the court failed to take the statements of eyewitnesses of the events or of members of the presumed victim’s family who could have provided essential information, and omitted to make an on-site inspection. 302 because the implementation of The latter resulted in financial expenditure for the complainant, the measures was conditioned on the complainant obtaining transport, and this expenditure was not reimbursed when the measure was not taken (supra para. 80). In addition, no information was requested with regard to the military personnel serving on the Cajatambo Contra-subversive Military Base, which belonged to the 77th Armored Infantry Battalion, during April 1991. The Court considers that these omissions in the said investigation were of an essential nature in order to 298 Cf. Case of Anzualdo Castro v. Peru. Preliminary objection, merits, reparations and costs, supra, para. 126. 299 Cf. Article I(b) of the Inter-American Convention on Forced Disappearance of Persons. See, also, Article 12 of the International Convention for the Protection of All Persons from Enforced Disappearance. 300 Cf. Case of Velásquez Rodríguez v. Honduras. Merits, supra, para. 174, and Case of Anzualdo Castro v. Peru. Preliminary objection, merits, reparations and costs, supra, para. 135. 301 Cf. Case of Tiu Tojin v. Guatemala. Merits, reparations and costs. Judgment of November 26, 2008. Series C No. 253, para. 327, and Case of the Massacres of El Mozote and nearby places v. El Salvador, supra, para. 313. 302 Cf. Brief addressed to the Cajatambo Investigating Judge of December 6, 1991 (evidence file, volume IV, annex 48 to the submission of the case, folio 1832). 68