22 measures to increase security in the zone but that events such as this are unavoidable. The State notes that Joe Luis Castillo González had not requested protection measures nor reported any threats against him. 92. Based on the arguments of the parties, as well as on information in the record, the Commission finds that analyzing the alleged responsibility of the State is most complex, given that there are different versions as to the background, motives, and even actors involved in the attack. Thus, for instance, there is evidence that could connect the events with Joe Luis Castillo González’s work as a human rights defender in regard both to land claims and to provision of assistance to refugees. Furthermore, the State has acknowledged the violence and danger in the area as result of its proximity to the Colombian border and the activities of paramilitary groups. With regard to this point, in the domestic proceeding reference was made to the existence of a list of targets of paramilitary groups which included the name of Joe Luis Castillo González because of the view that he had helped to shelter guerrillas. It has also been mentioned that paramilitary groups have a number of links to landowners in the area and to State authorities, who were aware of their criminal activities and even collaborated with them. 93. The Commission finds that the linking of certain of these elements to the facts in the instant case could lead to different hypotheses about the responsibility of the State in the death of Joe Luis Castillo González and the injuries to his wife and son. Therefore, based on the evidence contained in the record, the available information as to context, and the investigations carried out at the domestic level, the Commission will analyze the facts in the light of: i) the duty to prevent violations; ii) indicia of direct involvement of agents of the State; and, iii) the investigations at the domestic level. 1.1 The duty to prevent violations 94. The Inter-American Court has found with respect to the right enshrined in Article 4 of the American Convention that [...] the right to life plays a key role in the American Convention as it is the essential corollary for realization of the other rights.112 When the right to life is not respected, all the other rights lack meaning. The States have the obligation to ensure the creation of such conditions as may be required to avoid violations to this inalienable right and, specifically, the duty of avoiding attempts against it by the agents of the State.113 Compliance with Article 4, in combination with Article 1(1) of the American Convention, not only requires that no person be deprived of his life arbitrarily (negative obligation), but also that the States take all appropriate measures to protect and preserve the right to life (positive obligation), as part of their duty to ensure full and free exercise of the rights by all persons under their jurisdiction.114 95. With respect to fulfillment of the duty to ensure rights, the case law of the organs of the Inter-American system indicates that said duty includes aspects, such as prevention, protection, and investigation. When these requirements are not met, States may engage their international responsibility for violation of the right to life. 112 I/A Court H.R., Case of the Miguel Castro-Castro Prison v. Peru. Judgment of November 25, 2006. Series C No. 160, par. 237; I/A Court H.R., Case of the Massacre of Pueblo Bello v. Colombia. Judgment of January 31, 2006. Series C No. 140, par. 120; I/A Court H.R., Case of Huilca Tecse v. Peru. Judgment of March 3, 2005. Series C No. 121, par. 65. 113 I/A Court H.R., Case of Zambrano-Vélez et al. v. Ecuador. Judgment of July 4, 2007. Series C No. 166, par. 79; I/A Court H.R., Case of Montero Aranguren et al. (Detention Center of Catia) v. Venezuela. Judgment of July 5, 2006. Series C No. 150, par. 64; I/A Court H.R., Case of Ximenes Lopes v. Brazil. Judgment of July 4, 2006. Series C No. 149, par. 125; I/A Court H.R., Case of Baldeón García v. Peru. Judgment of April 6, 2006. Series C No. 147, par. 83; See also United Nations Human Rights Committee, General Comment 6/1982, para. 3 in Compilation of General Recommendations Adopted by Human Rights Treaty Bodies, U.N.Doc.HRI/GEN/1/Rev 1 en 6 (1994); United Nations Human Rights Committee, General Comment 14/1984, para. 1 in Compilation of General Recommendations Adopted by Human Rights Treaty Bodies, U.N.Doc.HRI/GEN/1/Rev 1 en 18 (1994). 114 I/A Court H.R., Case of Vargas-Areco v. Paraguay. Judgment of September 26, 2006. Series C No. 155, par. 75; I/A Court H.R., Case of the Ituango Massacres v. Colombia. Judgment of July 1, 2006. Series C No. 148, par. 130; I/A Court H.R., Case of the Indigenous Community Sawhoyamaxa v. Paraguay. Judgment of March 29, 2006. Series C No. 146, par. 152.