28 constitute an imminent threat of serious injury or death and those persons who do not represent that 139 threat, and use force only against the former.” 114. The Commission recalls that the use of excessive or disproportionate force by law 140 enforcement officials results in the loss of life, and may be equivalent to the arbitrary deprivation of life. Therefore, once the State learns that its security forces have resorted to firearms and, as a result, the loss of life has occurred, it is obligated to initiate ex officio and without delay, a serious, independent, 141 impartial and effective investigation. This is based on the obligation of the States to “ensure that their security forces, whom they have empowered with the legitimate use of force, respect the right to life of 142 those persons who are under their jurisdiction.” Furthermore, in cases of alleged extrajudicial executions, […] it is essential that the States effectively investigate the deprivation of the right to life, and in its case, punish all those responsible, especially when state agents are involved, since on the contrary, it would be creating, within an environment of impunity, the conditions necessary for the repetition of this type of facts, which is contrary to the duty to respect and guarantee the right to life. Besides, if the acts that violate human rights are not investigated seriously, they would, in some 143 way, result aided by public power, which compromises the State’s international responsibility. 115. The United Nations Manual on the Effective Prevention and Investigation of Extra-Legal, Arbitrary and Summary Executions provides investigative guidelines which should be followed whenever it is believed that a death may have been the result of an extra-legal execution. For its part, the European Court of Human Rights has outlined the elements of an effective investigation in order to evaluate the legality of the use of lethal force. In the Court’s words: […] the essential purpose of such investigation is to secure the effective implementation of the domestic laws which protect the right to life, and, in those cases involving State agents or bodies, to ensure their accountability for deaths occurring under their responsibility. The investigation must be independent, accessible to the relatives of the victim, completed within a reasonable period of time, effective in the sense that it is capable to lead to a determination of whether the use of force used in such cases was or was not justified in the circumstances or if it was legal, there must be 144 sufficient element of public scrutiny of the investigation or its results. …continuación control, storage and issuing of firearms, including procedures for ensuring that law enforcement officials are accountable for the firearms and ammunition issued to them; ( e ) Provide for warnings to be given, if appropriate, when firearms are to be discharged; ( f ) Provide for a system of reporting whenever law enforcement officials use firearms in the performance of their duty. 139 IA Court H.R., Case Zambrano Vélez et al Vs. Ecuador. Merits, Reparations and Costs. Judgment dated July 4, 2007. Series C No. 166, par. 85; in a similar sense, IACHR, Report on Terrorism and Human Rights 2002. 140 IA Court H.R., Case Zambrano Vélez et al Vs. Ecuador. Merits, Reparations and Costs. Judgment dated July 4, 2007. Series C No. 166, par. 85. 141 IA Court H. R., Case Zambrano Vélez et al Vs. Ecuador. Merits, Reparations and Costs. Judgment dated July 4, 2007. Series C No. 166, par. 88; IA Court H.R., Case Juan Humberto Sánchez Vs. Honduras. Judgment dated June 7, 2003. Series C No. 99, par. 112. Also see Case of the Miguel Castro Castro Prison vs. Peru. Judgment dated November 25, 2006. Series C No. 160, par. 256, and IA Court H.R., Case Vargas Areco Vs. Paraguay. Judgment dated September 26, 2006. Series C No. 155, par.77. In a similar sense also see ECHR, Erdogan and Others v. Turkey, supra nota 66, pars.122-123,0 and ECHR, Nachova and Others v. Bulgaria [GC], nos. 43577/98 and 43579/98, pars. 111-112, 6 July 2005. Also see, IACHR, Report on citizen security and human rights, OEA/Ser.L/V/II., Doc. 57, December 31, 2009, par. 120. 142 IA Court H.R., Case Zambrano Vélez et al Vs. Ecuador. Merits, Reparations and Costs. Judgment dated July 4, 2007. Series C No. 166, par. .81; IA Court H.R., Case Montero Aranguren et al (Retén de Catia) Vs. Venezuela. Judgment dated July 5, 2006. Series C No. 150, par. 66. Also see IA Court H.R., Case of the Penal Miguel Castro Castro vs. Peru. Judgment dated November 25, 2006. Series C No. 160, par. 238, and IA Court H.R., Case Servellón García et al vs. Honduras. Judgment dated September 21, 2006. Series C No. 152, par. 102. 143 IA Court H.R., Case Servellón García et al Vs. Honduras. Judgment dated September 21, 2006. Series C No. 152, par. 123; IA Court H.R., Case Baldeón García vs. Perú. Judgment dated April 6, 2006. Series C No. 147, par. 91; IA Court H.R., Case of the Massacre of Pueblo Bello vs. Colombia. Judgment dated January 31, 2006. Series C No. 140, par. 145; IA Court H.R., Case of the ”Massacre of Mapiripán” Vs. Colombia. Judgment dated September 15, 2005. Series C No. 134, pars. 137 y 232. 144 ECHR. Hugh Jordan v. the United Kingdom, no. 24746/94 par. 105-109, 4 May 2001.