164. With respect to this duty to exhaust the lines of investigation related to the practice of journalism, the IACHR acknowledges that, from the beginning of the investigation, the State took steps to investigate the relationship between Nelson Carvajal Carvajal’s murder and his work. As discussed previously, the Prosecutor’s Office worked this line of investigation as the sole logical theory for the journalist’s murder and, in accordance with the law, transferred the investigation to the Regional Prosecutor’s Office in Bogotá. 165. It bears repeating that when it is suspected that the act may be attributable to criminal organizations operating with the tolerance or sponsorship of State authorities, or when persons in government or related to government have attempted to obstruct the murder investigation, due diligence in the investigations necessarily entails taking account of the patterns of conduct of these power structures, which, in order to guarantee impunity, generally use outside pressures, attacks, threats, and other forms of intimidations against judges, prosecutors, witnesses, and other persons involved in criminal investigations. 166. The Commission underscores that it is clear from the statements provided and the characteristics of the crime that several persons were involved, not only as direct perpetrators and masterminds but also as accessories after the fact, through the perpetration of serious threats on relatives of the victim, witnesses or other persons involved in the quest of finding the truth of the facts. Even more, there is information regarding the murder of a witness – Pablo Emilio Bonilla Betancurt – that could be related to his participation in the reopening of the investigation of the killing of Nelson Carvajal Carvajal. In this respect, the IACHR notes that the State has failed to demonstrate that it has conducted investigations to shed light on the relationship between the threats received by Nelson Carvajal’s relatives and by the witnesses and the perpetrators of the crime. There is also no indication that, for purposes of identifying all of the perpetrators, the potential connection has been explored between the violent death of witness Pablo Emilio Bonilla Betancurt—which occurred after he provided statements in the case for the reconsideration of the acquittals—and the murder of journalist Carvajal. Similarly, there is no indication that the authorities have followed up on the body of evidence that pointed to the involvement of the mayor of Pitalito as mastermind or accessory to the crime. The State made no observations with respect to the matter. 167. The IACHR further notes that the petitioner complained that the courts disregarded key witnesses who corroborated the defendants’ guilt and received fraudulent statements to divert the investigations toward the potential responsibility of the FARC. One defense witness who maintained that the FARC masterminded the crime was allegedly an occasional informant of the “Magdalena” Infantry Battalion No. 27 and was facing four cases of abuse of process, criminal deception, and public and private document fraud. 168. Similarly, and as evident from the case file, the Prosecutor’s Office itself called the theory implicating the FARC in the murder of journalist Carvajal Carvajal inconsistent and a “setup” meant to clear the defendants of criminal wrongdoing and allow for their acquittal in the case. This information was provided to the authorities, however, there is no indication that it has been investigated. On November 29, 2000, the Special Prosecutor handling the Nelson Carvajal Carvajal case stated at trial before the Criminal Court of the Specialized Circuit of Neiva156 that this theory was unfounded, asserting that: “we have gotten used to blaming the guerrillas for everything.” She stated that, in Colombia, “they are accused of any act in order for the perpetrator to remain innocent, and one more crime goes unpunished.” 169. The IACHR observes that, in spite of these complaints, the authorities responsible for the pretrial phase of the criminal proceeding have continued the investigation into the alleged responsibility of the FARC guerrillas; to date, two members of the guerrilla, alias “El Corcho” and alias “Oswaldo Patiño,” reportedly remain implicated in the case without any specific outcome after more than a decade of 156 Attachment 18. Criminal Court of the Specialized Circuit of Neiva, Huila. Public trial proceedings in Case No. 2000-0090. Prosecution of Fernando Bermúdez Ardila, Víctor Félix Trujillo, and Alfaro Quintero Alvarado, for the offense of murder. Hearing No. 047. November 29, 2000, pp. 23-24. Attachment to the petitioner’s communication of August 25, 2005.