138. Although the duty to investigate is one of means, not results, it must be assumed by the State as its own legal duty and be undertaken in a serious manner and not as a mere formality preordained to be ineffective,143 or simply as a step taken by private interests that depends upon the initiative of the victim or his family or upon their offer of proof.144 139. With respect to the state’s obligation to investigate complaints of forced disappearance of persons, the Court has held that “faced with the particular gravity of such offenses and the nature of the rights harmed, the prohibition of the forced disappearance of persons and the corresponding obligation to investigate and punish those responsible has attained the status of jus cogens.”145 Hence, whenever there are reasonable motives to suspect that a person has been subjected to forced disappearance an investigation should be opened ex oficio, without delay, and in a serious, impartial, and effective manner. in any case, every state authority, public or private officer who is aware of acts intended to forcibly disappear persons, shall immediately report them.146 140. As regards the guarantee of reasonable time, the Court has determined that three elements should be taken into account to determine the fairness of the time incurred: a) the complexity of the matter, b) the procedural activities carried out by the interested party, and c) the conduct of judicial authorities.147 In its more recent cases, the Court has included a fourth element: the effects that a delay in the proceeding might have on the legal situation of the victim.148 141. It is appropriate to analyze, in light of the standards set forth in the foregoing paragraphs, whether the Ecuadorian State conducted criminal investigations, and if it did, whether they were conducted with due diligence and within a reasonable period of time, and whether they constituted effective remedies for ensuring the victim's right to have access to justice. 142. Although in cases of forced disappearance it is essential for prosecutors and the judiciary to act immediately, ordering the steps needed to determine the whereabouts of the victim or the place where he or she may be deprived of their liberty,149the State has not pointed to, and the case file with the IACHR makes no reference to, any specific action of that nature. 143. Thus, as established in the chapter on proven facts, it transpires from the case file with the IACHR that the Ecuadorian authorities were informed through various channels -- diplomatic, inter-American human rights system, International Red Cross, and others -- regarding the detention of Mr. Jorge Vásquez Durand in January 1995 and his subsequent disappearance. 143 I/A Court H.R., Velásquez Rodríguez v. Honduras. Judgment of July 29, 1988. Series C No. 4, paragraph 177; Case of Cantoral-Huamaní and García-Santa Cruz v. Peru. Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, paragraph 131; and Case of Zambrano-Vélez et al. v. Ecuador. Merits, Reparations and Costs. Judgment of July 4, 2007. Series C No. 166, paragraph 120. 144 I/A Court H.R., Velásquez Rodríguez v. Honduras. Judgment of July 29, 1988. Series C No. 4, paragraph 177; and Case of Zambrano-Vélez et al. v. Ecuador. Merits, Reparations and Costs. Judgment of July 4, 2007. Series C No. 166, paragraph 120. 145 I/A Court H.R., Case of Goiburú et al v. Paraguay. Merits, Reparations and Costs. Judgment of September 22, 2006. Series C No. 153, paragraph 84; Case of Anzualdo Castro v. Peru, Judgment of September 22, 2009, Series C No. 202, paragraph 59; and Case of Radilla Pacheco v. Mexico. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 23, 2009. Series C No. 209, paragraph 139. 146 I/A Court H.R, Case of Anzualdo Castro v. Peru, Judgment of September 22, 2009, Series C No. 202, paragraph 65, and Case of Radilla Pacheco v. Mexico, Preliminary Objections, Merits, Reparations and Costs. Judgment of November 23, 2009. Series C No. 209, paragraph 143. 147 I/A Court H.R., Case of Escué-Zapata. Merits, Reparations and Costs. Judgment of July 4, 2007. Series C No. 165, paragraph 72; and Case of La Cantuta. Judgment of November 29, 2006, Series C No. 162, paragraph 102. 148 I/A Court H.R., Case of Kawas-Fernández v. Honduras. Merits, Reparations and Costs. Judgment of April 3, 2009, paragraph 196; and Case of Valle Jaramillo et al. v. Colombia. Merits, Reparations and Costs. Judgment of November 27, 2008. Series C No. 192 149 I/A Court H.R, Case of Anzualdo Castro v. Peru, Judgment of September 22, 2009, Series C No. 202, paragraph 134. 33