a) Based on the gravity of the facts, it may not apply amnesty laws or argue prescription, the non-retroactivity of criminal laws, res judicata, or the non bis in idem principle, or any other similar mechanism that excludes responsibility, in order to waive its obligation to investigate and prosecute those responsible;331 b) It must investigate the facts of this case ex officio and effectively, taking into account the systematic pattern of grave and massive human rights violations that existed at the time they occurred. In addition to the violation of the right to life, the State must consider other possible grave violations of the right to personal integrity and to personal liberty, in particular the presumed acts of forced disappearance, torture, extrajudicial execution, rape, slavery and involuntary servitude, taking into account also the differentiated impact of the alleged violations on the children and women of the community of Río Negro.332 The State must also execute the pending arrest warrants for those presumably responsible and issue any that are pertinent in order to prosecute all those responsible for the facts of this case; c) It must determine the identity of all the alleged masterminds and perpetrators of the massacres and the subsequent persecution of the members of the community of Río Negro; consequently, is must conclude the criminal proceedings opened against them, and proceed to investigate the presumed authors who have not yet been identified. Due diligence in the investigation means that all the State authorities are obliged to collaborate in the gathering of evidence; thus they must provide the judge of the case with all the information that he requests and abstain from acts that obstruct the investigative process; d) It must open the disciplinary, administrative or criminal actions, under its domestic legislation, against those State authorities who have possibly obstructed or prevented the due investigation of the facts, as well as those responsible for the different procedural irregularities that have contributed to prolonging the impunity of the massacres, and e) It must ensure that the different organs of the justice system involved in the case have the necessary human and material resources to perform their tasks adequately, independently and impartially, and that those who participate in the investigation, including the victims or their representatives, witnesses, and justice officials, are granted adequate guarantees as regards their safety. 258. In accordance with its consistent case law,333 the Court considers that the State must ensure full access and legal standing to the victims or their next of kin at all the stages of the investigation and prosecution of those responsible, in keeping with domestic law and the provisions of the American Convention. In addition, the results of the 331 Cf. Case of Barrios Altos v. Peru. Merits. Judgment of March 14, 2001. Series C No. 75, para. 41, and Case of González Medina and family members v. Dominican Republic, supra, para. 285(e). 332 Cf. Case of the Dos Erres Massacre v. Guatemala, supra, para. 233(b). In its General Recommendation No. 19: “Violence against women,” the Committee for the Elimination of Discrimination against Women established that States are required to adopt protective and punitive measures. It also recommended that laws against violence respect the integrity and dignity of all women, and that States provide protection for victims, as well as encourage research on the causes and effects of violence and on the effectiveness of measures to prevent and deal with violence, and provide effective procedures for reparation, including compensation. 333 Cf. Case of El Caracazo v. Venezuela. Reparations and costs. Judgment of August 29, 2002. Series C No. 95, para. 118, and Case of Pacheco Teruel et al. v. Honduras, supra, para. 130. 89