of the victims or their families to carry out a procedure or on the private contribution of elements of evidence.131 The obligation of the State to investigate must be dutifully accomplished in order to avoid impunity and to prevent these types of events to happen again.132 80. In addition, regarding due diligence during the development of the investigation, the Commission and the Inter-American Court have established that “every state proceeding that is part of the process of investigation, as well as the complete investigation itself, must be oriented to a specific purpose, the discovery of the truth and the investigation, persecution, capture, prosecution and, when appropriate, the punishment of the persons responsible for the facts”.133 In this regard, the State must prove that it has carried out an immediate, exhaustive, serious and unbiased investigation, 134which has to be oriented to study every possible line of investigation.135 The State could be held responsible for the failure to “gather, practice or value evidence” which could be essential for the proper clarification of the facts.136 81. In line with the foregoing, the Court has reaffirmed the importance, specifically in the Colombian case, for investigations of these type of responsibilities to be conducted in the scope of the criminal jurisdiction mainly and for other types of adjunct enquires, as the ones carried out by the General Prosecutor’s Office in the scope of the disciplinary processes, to be able to complement, but never substitute, the criminal aspect of the investigations on serious violations of human rights.137 82. In addition, the Court has established the State’s duty to investigate the facts as long as there is uncertainty over the whereabouts of the missing person and to provide a simple and rapid action for the case, with the corresponding guarantees.138 The Commission wants to remind that in this sense all States must guarantee the right to the truth for the victim or his or her family through the investigation and prosecution mentioned in Articles 8 and 25 of the Convention.139 83. Ultimately, regarding the beginning of the reasonable time referred to in Article 8.1 of the American Convention, the Inter-American Court has established that it is precise to consider three elements in order to determine the reasonableness of the period of time during which a procedure is carried out: a) the complexity of the issue, b) the procedural activity of the interested party, and c) the judicial authorities’ behavior. 140 In addition, the Commission and the Court have also considered the interest of the affected party.141 131I/A Court of H.R. Case Velásquez Rodríguez Vs. Honduras. Merits. Judgment of July 29, 1988. Series C No. 1, para. 177; and Case Veliz Franco and others Vs. Guatemala. Preliminary Objections. Merits, Reparation and Costs. Judgment of May 19, 2014. Series C No. 277, para.183. 132 I/A Court of H.R. Case of the Ituango Massacres Vs. Colombia. Judgment of July 1, 2006, Series C No. 148, para. 319; Case Veliz Franco and others Vs. Guatemala. Preliminary Objection, Merits, Reparation and Costs. Judgment of May 19, 2014. Series C No. 277, para. 183; and Case Landaeta Mejías Brothers and others Vs. Venezuela. Preliminary Objection, Merits, Reparation and Costs. Judgment of August 27, 2014. Series C No. 281, para., 216. 133 I/A Court of H.R. Case Cantoral Huamaní and García Santa Cruz Vs. Peru. Preliminary Objection, Merits, Reparation and Costs. Judgment of July 10, 2007. Series C No. 167, para. 131; I/A Court of H.R., Case Kawas Fernández Vs. Honduras. Merits, Reparation and Costs. Judgment of April 3, 2009, Series C No. 196, para. 101; IACHR, Report No. 85/13, Case 12.251, Admissibility and Merits, Vereda la Esperanza, Colombia, November 4, 2013, para. 242. 134 IACHR, Merits Report No. 55/97, Juan Carlos Abella and Others (Argentina), November 18, 1997, para. 412. 135 IACHR, Report No. 25/09 Merits (Sebastião Camargo Filho) Brasil, March 19, 2009, para. 109. See also, IACHR, Access to Justice for Women Victims of Violence in the Americas, OEA/Ser. L/V/II. doc.68, January 20, 2007, para. 41. 136 I/A Court of H.R. Case of the “Children in the Street” (Villagrán Morales and others) Vs. Guatemala. Judgment of November 19, 1999. Series C No. 63, para. 230. See also, IACHR, Access to Justice for Women Victims of Violence in the Americas, OEA/Ser. L/V/II. doc.68, January 20, 2007, para. 41. 137 I/A Court of H.R. Case of La Rochela’s Massacre Vs. Colombia. Interpretation of the Judgment on Merits, Reparation and Costs. Judgment of January 28, 2008. Series C No. 175; Case of the Ituango Massacres, para. 333; and Case of Pueblo Bello’s Massacre, para. 203. 138 I/A Court of H.R., Case Bámaca Velásquez Vs. Guatemala. Merits. Judgment of November 25, 2000. Series C No. 70, para. 197. 139 IACHR. Right to the Truth in the Americas. OEA/Ser.L/V/II.152. Doc. 2. August 13, 2014. Para. 13. 140 I/A Court of H.R. Case Vargas Areco Vs. Paraguay. Judgment of September 26, 2006. Series C No. 155, para. 196; Case of the Ituango Massacres Vs. Colombia. Judgment of July 1, 2006, Series C No. 148, para. 289; and I/A Court of H.R. Case Baldeón García Vs. Peru. Merits, Reparation and Costs. Judgment of April 6, 2006. Series C No. 147, para. 151. 141 I/A Court of H.R. Case Valle Jaramillo and others Vs. Colombia. Merits, Reparation and Costs. Judgment of November 27, 2008. Series C No. 192, para. 155. 19