41 whether the state should resort to the use of fireams and under which circumstances, must be decided on the basis of clear legal rules and adequate training.134 78. In this sense, the Court deems that it is essential for government officers to know the legal rules that authorize the use of firearms and to have the adequate training so that they may have the elements of judgment necessary to be able to decide whether to use them or not under certain circumstances. Moreover, the States must restrict to the maximum extent the use of armed forces to control domestic disturbances, since they are trained to fight against enemies and not to protect and control civilians, a task that is typical of police forces. v) Adequate control and verification of the legality of use of force. 79. Likewise, the general prohibition imposed on government officers to arbitrarily kill people would be practically ineffective if there were not any procedures to verify the legality of the use of lethal force by government officers. Upon learning that member of the security forces have used firearms causing lethal consequences, the State must immediately initiate a rigorous, impartial and effective investigation ex officio135. 80. Whenever the use of force caused the death or injuries to one o more people, the State should give a satisfactory and convincing explanation of the events and rebut the allegations related to its liability, by means of adequate evidence. 81. Furthermore, in this kind of cases the reasonable measures adopted by competent authorities to secure the evidence necessary for the investigation136 are particularly important as well as the de jure and de facto independence of the officers involved in the incidents137. This requires not only hierachical or institutional independence, but actual independence. 82. On the other hand, the European Court of Human Rights held that investigations on excessive use of force must be subject to public scrutiny to secure 134 Cf. ECHR, Case of Erdogan and Others v. Turkey, supra note 129, para. 68; ECHR, Case of Kakoulli v. Turkey, supra note 129, para. 109-110; ECHR, Case of Kilic v. Turkey. Judgment of March 28, 2000. Application No. 22492/93, para. 62. 135 Cf. Case of Baldeón García, supra note 3, para. 92; Case of the Pueblo Bello Massacre, supra note 6, para. 143 and Case of the “Mapiripán Massacre”, supra note 7, para. 219. En el mismo sentido, Cf. ECHR, Case of Erdogan and Others v. Turkey, supra note 129, paras. 88-89; ECHR, Case of Kakoulli v. Turkey. supra note 129, paras. 122-123; ECHR, Case of Nachova and others v. Bulgaria [GC]. Judgment of 6 July 2005. Application Nos. 43577/98 and 43579/98, paras. 111-112. 136 Cf. ECHR, Case of Erdogan and Others v. Turkey, supra note 129, paras. 89; ECHR, Case of Kakoulli v. Turkey, supra note 129, paras. 123; ECHR, Case of Hugh Jordan v. the United Kingdom. Judgment of 4 May 2001. Application No. 24746/94, para. 107-108. 137 Cf. Case of Durand and Ugarte. Judgment of August 16, 2000. Series C No. 68, paras. 125 and 126; and ECHR, Case of Nachova and others v. Bulgaria [GC], supra note 135, para. 112; ECHR, Case of Isayeva v. Russia. Judgment of February 24, 2005. Application No. 57950/00, para. 211; ECHR, Case of Kelly and Others v. The United Kingdom. Judgment of 4 May 2001. Application No. 30054/96, para. 95.