39 violated right and provide compensation as warranted for damages resulting from the violation. 104 The obligation to investigate human rights violations is one of the positive measures that States must adopt to ensure the rights recognized in the Convention. 105 129. The Court has written that victims and their families have the right to expect, and the States the obligation to ensure, that what befell the alleged victims will be investigated effectively by the State authorities; that proceedings will be filed against those allegedly responsible for the unlawful acts; and, if applicable, the pertinent penalties will be imposed, and the losses suffered by the next of kin redressed. 106 Accordingly, once the state authorities know of a human rights violation, particularly violations of the right to life, the right to humane treatment and the right to personal liberty, 107 their duty is to initiate a serious, impartial and effective investigation, ex officio and without delay 108 and carried out within a reasonable period. 109 130. As to the meaning of the duty to investigate “with due diligence,” the Inter-American Court has written that due diligence implies that the investigations are to be conducted by all legal means available and should be geared to establishing the truth.” 110 The Court has also written that the State has a duty to ensure that everything necessary is done to ascertain the truth of what happened and to punish anyone responsible, 111 and that every State institution must be involved. 112 131. For its part, the Inter-American Commission has written the following with regard to the States’ obligation to conduct a serious investigation: [T]he fact that no one has been convicted in the case or that, despite the efforts made, it was impossible to establish the facts does not constitute a failure to fulfill the obligation to investigate. However, in order to establish in a convincing and credible manner that this result was not the product of a mechanical implementation of certain procedural formalities 104 I/A Court H.R., Case of Velásquez Rodríguez v. Honduras. Judgment of July 29, 1988. Series C No. 4, paragraph 166. I/A Court H.R., Case of Juan Humberto Sánchez v. Honduras. Judgment of June 7, 2003. Series C No. 99, paragraph 74. I/A Court H.R., Case of Ximenes Lopes. Judgment of July 4, 2006. Series C No. 177. 105 106 I/A Court H.R., Case of García Prieto et al. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 20, 2007. Series C No. 168, paragraph 103; I/A Court H.R., Case of Bulacio. Preliminary Objections, Merits, Reparations and Costs. Judgment of September 18, 2003. Series C No. 100, paragraph114; and I/A Court H.R., Case of the Miguel Castro Castro Prison. Judgment of November 25, 2006. Series C No. 160, paragraph 382. 107 I/A Court H.R., Case of Cantoral Huamaní and García Santa Cruz. Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, paragraph 100. 108 I/A Court H.R., Case of García Prieto et al. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 20, 2007. Series C No. 168, paragraph 101; I/A Court H.R., Case of the Gómez Paquiyauri Brothers. Judgment of July 8, 2004. Series C No. 110, paragraph 146; I/A Court H.R., Case of Cantoral Huamaní and García Santa Cruz, Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, paragraph 130. 109 I/A Court H.R., Case of Bulacio. Judgment of September 18, 2003. Series C No. 100, paragraph 114; I/A Court H.R., Case of the Rochela Massacre. Judgment of May 11, 2007. Series C. No. 163, paragraph 146; I/A Court H.R., Case of the Miguel Castro Castro Prison. Judgment of November 25, 2006. Series C No. 160, paragraph 382. I/A Court H.R., Case of García Prieto et al. Preliminary Objection, Merits, Reparations and Costs. Judgment of November 20, 2007. Series C No. 168, paragraph 101. 110 111 I/A Court H.R., Case of Bulacio. Judgment of September 18, 2003. Series C No. 100, paragraph 114; I/A Court H.R., Case of the Rochela Massacre. Judgment of May 11, 2007. Series C. No. 163, paragraph 146; I/A Court H.R., Case of the Miguel Castro Castro Prison. Judgment of November 25, 2006. Series C No. 160, paragraph 382. I/A Court H.R., Case of Cantoral Huamaní and García Santa Cruz. Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, paragraph 130; I/A Court H.R., Case of the Pueblo Bello Massacre. Judgment of January 31, 2006. Series C No. 140, paragraph 120; and I/A Court H.R., Case of Huilca Tecse. Judgment of March 3, 2005. Series C No. 121, paragraph 66. 112