55 context of the facts, their complexity, the patterns that explain their perpetration, the complex structure of individuals involved, or the special position within the State structure at that time of those who could be responsible. On this point, the Court has found that, with facts such as the ones alleged in this case, given their context and complexity, it is reasonable to consider that there are different degrees of responsibility at different levels.241 However, this is not reflected in the investigations. Consequently, the authorities in charge of the investigations do not appear to have followed clear and logical lines of investigation that would have taken those elements into account. Furthermore, obvious omissions can be observed in the collection of evidence. In this regard, the Court finds that the State has not been diligent with regard to this obligation. 151. In addition, the Court observes that, even though, on December 12, 2006, the reunion between Gregoria Herminia Contreras and her biological parents was made public,242 and communicated by the representatives during the proceedings before the Inter-American Commission,243 there is no record of any actions taken to receive her testimony, with due guarantees, avoiding possible re-victimization. The only measure in this regard was the request made on June 9, 2010, to the Search Association for a certified copy of the information relating to “the reappearance of Gregoria Erminia Contreras [sic].”244 Moreover, the State has not opened investigations into the facts of the appropriation and registration of Gregoria Herminia in the civil registry of the Santa Ana Mayor’s Office with false information (supra para. 111), or into any other related fact. 152. Likewise, there is no indication that steps have been taken to determine the possible location of the children whose whereabouts are still unknown in accordance with the modus operandi concerning the disappearance of children during the armed conflict, such as notifying and, if appropriate, inspecting the records and files of orphanages, children’s homes, hospitals, medical institutions, and military premises, as well as requesting information from the International Committee of the Red Cross and the Salvadoran Red Cross to determine whether, at the time, the children were attended to in any of their facilities, obtaining information on adoption proceedings before the Minors Courts and the adoption records of the period, and obtaining information on children registered as leaving by way of the airport during the relevant period, as well as of individuals who died without being identified in the age range. All this should have been done in the understanding that many of the children lacked identification documents, their original names were changed or they were registered in the municipal mayors’ offices with other names and surnames, or their family registration was changed to include the death of their parents through annotations or the addition of false death certificates.245 Moreover, since a systematic pattern was involved in which numerous authorities could be involved, and which included cross-border movements, in this case, the State should have used and applied the appropriate legal tools to the analysis of the case, including the required inter-State cooperation.246 241 Cf. Case of Radilla Pacheco, supra note 25, para. 203, and Case of Ibsen Cárdenas and Ibsen Peña, supra note 100, para. 171. 242 Cf. Newspaper article that appeared in El Diario de Hoy, supra note 78. 243 Cf. Note of the Search Association of December 14, 2006, received by the Inter-American Commission on April 3, 2007 (evidence file, volume II, appendix 3, folio 842). 244 File 585-UDVSV-2008, supra note 223, (evidence file, volume X, attachment 3 to the answer to the application, folios 6659 to 6686 and 6703 to 6704). 245 Cf. Expert opinion provided by Ana Georgina Ramos de Villalta, supra note 35, (evidence file, volume XI, affidavits, folios 7535 to 7537). 246 Cf. Case of Gelman, supra note 16, para. 234.