265. The Court has previously held that the obligation to investigate, prosecute and, as appropriate, punish those responsible for human rights violations is an affirmative measure that the States must adopt in order to guarantee the rights recognized in the Convention,326 in accordance with Article 1(1) thereof. The State must assume this duty as a legal obligation and not simply as a formality that is preordained to be ineffective, or as a mere response to private interests, which relies upon the procedural initiative of the victims or their next of kin, or on the production of evidence by private parties.327 266. The Court has also stated that the obligation to investigate, and the corresponding right of the alleged victims or their next of kin, derive not only from the treaty-based norms of international law, which are mandatory for the States Parties, but also from domestic law regarding the duty to investigate ex officio certain unlawful actions and the rules that allow victims or their families to report or file complaints, present evidence or petitions or take any other measure, in order to have legal standing in the criminal investigation in the hope of establishing the truth of the facts. 328 267. In this case, the Court observes that several complaints were filed in relation to the alleged attacks and threats against members of the Sarayaku People (supra para. 107). 268. There is no indication of any measures taken or results related to the complaint filed before the Pichincha District Prosecutor by José Serrano in April 2004. 269. In addition to the official investigation begun, ex officio, by the Pastaza Ombudsman in connection with the events that took place on December 4, 2003 (supra para. 112), the Court observes that the Pastaza Prosecutor took some investigative measures329 in response to the complaint filed (supra para. 113). Despite this, no probative documents were submitted that would allow the Court to determine whether any action or final or provisional decision was taken by the authorities in relation to the alleged events. Regarding the other complaints, the Court finds that the parties did not furnish any probative documents or specific arguments to determine whether an investigation or some sort of verification process was carried out as a result of the complaints filed. Also, no documentation was provided regarding any final or temporary decision by the authorities in relation to the alleged events. 270. In short, the Court observes that no investigation was opened in five of the six complaints filed and that, regarding the investigation that was opened, there is evidence of procedural inactivity after certain measures had been taken. Although the State argues that this inactivity was due to lack of access to the territory of the Sarayaku People, it did not provide any probative documentation regarding any final action or decision by the authorities in connection with the investigation of the complaints filed that contains this or any other explanation for not continuing with the investigations. Thus, the Court finds that, in this case, the investigations were not an effective measure to guarantee the rights to personal integrity of the presumed victims of these acts. 271. Based on the foregoing considerations, the Court finds that, in this case, the flaws in the investigation of the reported facts reveal that the State authorities did not act with due diligence or in accordance with their obligations to guarantee the right to personal integrity contained in Article 5(1) of the Convention, in relation to the State’s obligation to guarantee the rights established in 326 Cf. Case of Velásquez Rodríguez v. Honduras, Merits, paras. 166 and 167, and Case of Torres Millacura et al. v. Argentina, para. 112. 327 Cf. Case of Velásquez Rodríguez v. Honduras, Merits, para. 177, and Case of Torres Millacura et al. v. Argentina, para. 112. 328 Cf. Case of the Barrios Family v. Venezuela, para. 80, and Case of García Prieto et al. v. El Salvador. Preliminary objections, merits, reparations and costs. Judgment of November 20, 2007. Series C No. 168, para. 104. 329 Cf. Preliminary inquiry of December 9, 2003 (evidence file, tome 16, folios 9253 and 9254); Appointment of expert witnesses, December 9, 2003 (evidence file, tome 16, folio 9255); Legal-medical certificates of December 9, 2003 (evidence file, tome 16, folios 9256 to 9295); statements from suspects taken on May 4, 5, 14 and 20, June 4 and 8, 2004 (evidence file, tome 16, folios 9313 to 9370);witness statement of June 10, 2004 (evidence file, tome 16, folios 9371 to 9372), and report on the inspection of the scene of the incidents involving Sarayaku and Canelos, of April 23, 2004 (evidence file, tome 16, folios 9359 to 9360). 75