53 criminal complaint (supra para. 140), in which other facts were being investigated. The Court emphasizes that the analysis of this argument does not refer to the actions that the next of kin of Messrs. Ibsen Cárdenas and Ibsen Peña should have or should not have taken, but in view of the State’s obligation ex officio, the Tribunal shall analyze the steps taken by the State in that regard. 161. In relation to the situation of Mr. Rainer Ibsen Cárdenas, the Tribunal highlights that it has already been established in this Judgment that at the end of the dictatorship of Hugo Banzer Suarez in 1979, the National Congress Legislature had initiated an impeachment trial against, among others, the former president. As part of said process, on September 5, 1979, the ASOFAMD presented a list of the people who had been murdered or disappeared at the time of the events. This process was not carried on, however, the Court notes that in that list there appears the name of Rainer Ibsen Cárdenas (supra para. 56). On the other hand, at least since 1983, the State had evidence of what seemed to be the remains of Rainer Ibsen Cárdenas (supra para. 84), as the State itself asserted during the processing of this case. To that end, the State was fully aware of the fact that, apparently, a person had disappeared during the dictatorship of Hugo Banzer Suarez. However, it did not initiate an investigation into what happened to Rainer Ibsen Cárdenas. The State neither conducted the corresponding tests to corroborate his identity when in 1983 were found what it said to be his remains. Furthermore, the Tribunal must point out that the State has not effectively investigated what happened to Rainer Ibsen Cárdenas, given that the domestic criminal proceeding was only conducted regarding the facts that occurred to José Luis Ibsen Peña, despite the request to join the complaint filed by Ms. Rebeca Ibsen Castro (infra paras. 140 and 150). 162. Moreover, the State did not deny knowing about the disappearance of Mr. José Luis Ibsen Peña, but instead it made a broad acknowledgment of international responsibility for the facts of his detention and subsequent disappearance. 163. Based on the foregoing, it is clear to the Tribunal that the State has failed to comply with its duty to investigate ex officio the human rights violations committed against Messrs. Rainer Ibsen Cárdenas and José Luis Ibsen Peña. Therefore, the Court considers that the State violated Article 8(1) of the American Convention on Human Rights. B.2. Effective investigation and lack of diligence in the collection of evidence 164. The Inter-American Commission indicated that “in the few months devoted to collecting evidence, only [confessions] from the accused and testimonies from other persons were taken,” and that “the [a]vailable information does not show the existence of any other actions tending to refute the veracity of the official versions regarding the death of Rainer Ibsen in a “firefight,” nor of the alleged exile of José Luís Ibsen to Brazil.” The Commission asserted that the evidence available “demonstrates that the steps taken to clarify the facts with regard to Rainer Ibsen Cárdenas were minimal.” 165. The Tribunal considers that this aspect is closely related to the previous one. In that respect, the Court repeats its jurisprudence in the sense that the application of the guarantees of Article 8(1) of the American Convention is not limited to judicial activity. In particular, in relation to the investigations carried out by prosecution authorites, the Tribunal has established that, depending on the circumstances of the case, the Court may need to analyze the related proceedings and those that constitute procedural prerequisites, particularly the investigation tasks, the results of which will be important for the initiation