CCPR/C/GC/36 measures should be established by law and accompanied by effective institutional safeguards designed to prevent arbitrary deprivations of life. Furthermore, States that have not abolished the death penalty and that are not parties to the Second Optional Protocol to the Covenant, aiming at the abolition of the death penalty, or other treaties providing for the abolition of the death penalty can apply the death penalty only in a non-arbitrary manner, for the most serious crimes and subject to a number of strict conditions elaborated in part IV below. 11. The second sentence of article 6 (1) requires that the right to life be protected by law, while the third sentence requires that no one be arbitrarily deprived of life. The two requirements partly overlap in that a deprivation of life that lacks a legal basis or is otherwise inconsistent with life-protecting laws and procedures is, as a rule, arbitrary in nature. For example, a death sentence issued following legal proceedings conducted in violation of domestic laws of criminal procedure or evidence will generally be both unlawful and arbitrary. 12. Deprivation of life is, as a rule, arbitrary if it is inconsistent with international law or domestic law.23 A deprivation of life may, nevertheless, be authorized by domestic law and still be arbitrary. The notion of “arbitrariness” is not to be fully equated with “against the law”, but must be interpreted more broadly to include elements of inappropriateness, injustice, lack of predictability and due process of law, 24 as well as elements of reasonableness, necessity and proportionality. In order not to be qualified as arbitrary under article 6, the application of potentially lethal force by a private person acting in self-defence, or by another person coming to his or her defence, must be strictly necessary in view of the threat posed by the attacker; it must represent a method of last resort after other alternatives have been exhausted or deemed inadequate;25 the amount of force applied cannot exceed the amount strictly needed for responding to the threat;26 the force applied must be carefully directed, only against the attacker; and the threat responded to must involve imminent death or serious injury. 27 The use of potentially lethal force for law enforcement purposes is an extreme measure28 that should be resorted to only when strictly necessary in order to protect life or prevent serious injury from an imminent threat.29 It cannot be used, for example, in order to prevent the escape from custody of a suspected criminal or a convict who does not pose a serious and imminent threat to the lives or bodily integrity of others.30 The intentional taking of life by any means is permissible only if it is strictly necessary in order to protect life from an imminent threat.31 13. States parties are expected to take all necessary measures to prevent arbitrary deprivation of life by their law enforcement officials, including soldiers charged with law enforcement missions. These measures include putting in place appropriate legislation controlling the use of lethal force by law enforcement officials, procedures designed to ensure that law enforcement actions are adequately planned in a manner consistent with the need to minimize the risk they pose to human life,32 mandatory reporting, review and investigation of lethal incidents and other life-threatening incidents, and supplying forces responsible for crowd control with effective, less-lethal means and adequate protective equipment in order to obviate their need to resort to lethal force (see also para. 14 below).33 In particular, all operations of law enforcement officials should comply with relevant international standards, including the Code of Conduct for Law Enforcement Officials and the Basic Principles on the Use of Force and Firearms by Law Enforcement Officials,34 and law enforcement officials should undergo appropriate training designed to inculcate these standards35 so as to ensure, in all circumstances, the fullest respect for the right to life. 14. While preferable to more lethal weapons, States parties should ensure that less-lethal weapons are subject to strict independent testing and evaluate and monitor the impact on the right to life of weapons such as electro-muscular disruption devices (Tasers),36 rubber or foam bullets, and other attenuating energy projectiles,37 which are designed for use or are actually used by law enforcement officials, including soldiers charged with law enforcement missions.38 The use of such weapons must be restricted to law enforcement officials who have undergone appropriate training, and must be strictly regulated in accordance with applicable international standards, including the Basic Principles on the Use of Force and Firearms by Law Enforcement Officials. 39 Furthermore, less-lethal weapons must be employed only subject to strict requirements of necessity and proportionality, in situations in which other less harmful measures have proven to be or clearly are ineffective to address the 3