25 States must adopt all necessary measures to create a legal framework that deters any possible threat to the right to life; establish an effective legal system to investigate, punish, and redress deprivation of life by State officials or private individuals; and guarantee the right to unimpeded access to conditions for a dignified life. Especially, States must see that their security forces, which are entitled to use legitimate force, respect the right to life of the individuals under their 82 jurisdiction. 131. Given the nature of the facts in the present case, the Commission deems it necessary to recall the relevant standards regarding the use of force by state law-enforcement agencies. 132. The IACHR has written that while States have the right and the obligation to provide protection against threats and, to that end, may use lethal force under certain circumstances, that authority must be limited to what is strictly necessary and proportionate. Unless such exigencies exist, however, the lethal use of force may constitute an arbitrary deprivation of life or a summary execution; that is to say, the lethal use of force must necessarily be justified by a state’s right to protect the security of all.83 133. The Commission has also observed that the use of force may be justified, for example, in a case of self-defense or when necessary to neutralize or disarm individuals involved in armed conflict. However, if an individual loses his or her life as a result of the use of excessive or disproportionate force by law enforcement agents, that would be tantamount to an arbitrary deprivation of life.84 134. In this regard the Court has written that the use of force by governmental security forces must be premised on the existence of exceptional circumstances and should be planned and proportionally limited by the authorities. Here, the Court has established that force or coercive means can only be used once all other methods of control have been exhausted and failed.85 135. The Court held that the use of firearms and lethal force by law enforcement against persons -which must be generally forbidden- is only justified in even more extraordinary cases. The exceptional circumstances under which firearms and lethal force may be used shall be determined by the law and narrowly construed, so that in any case they are used to the minimum extent possible, but 82 I/A Court H.R., Case of Zambrano Vélez et al. v. Ecuador. Merits, Reparations and Costs. Judgment of July 4, 2007. Series C No. 166, paragraph 81; 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, paragraph 66. 83 IACHR. Report on Terrorism and Human Rights. OEA/Ser.L/V/II.116, doc. 5, paragraph 88. 84 IACHR. Report No.1/96, Case 10.559, Chumbivilcas (Peru). March 1, 1996; IACHR. Report No. 34/00, Case 11.291, Carandiru (Brazil). April 13, 2000, paragraphs 63, 67, 91. 85 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, paragraph 67.