Use of Drones and Global Security: Implications Under International Law

Erjon Hitaj

PHD, Sapienza University of Rome, Italy; Lecturer of Public International Law, University of Vlore «Ismail Qemali», Albania



The recent practice consisting in the use of drones in combat operations against non-state actors has provoked a large debate among international actors and legal scholars. Considered a non-traditional instrument of the use of force, the first issue of concern regards the ius ad bellum, which is the legal grounds of recourse to force and, on the other side, the ius in bello which explains the modalities of the use of force, once an armed conflict already exists. For these reasons, beside the fulfillment of the criteria established by art. 51 and Chapter VII of UN Charter on the use of force, the use of drones should also, in the context of legitimate armed attack, fully respect the criteria imposed by humanitarian international law such as proportionality, necessity and immediacy. With regard to self-defense, the use of drones under international law raises several legal questions mostly related to the pre-emptive or anticipatory nature of the use of force. Under current conventional and customary international law, the pre-emptive use of force is severally prohibited and thus, considered a violation of art. 2 (4) of the UN Charter. Self-defense, in order to be considered in conformity with art. 51 of the Charter, could be exercised in anticipatory way if an armed attack of the counter-part has already started. Outside the cases of self-defense and SC authorization, the use of drones (as a form of use of force) could be acceptable only in case of express territorial state consent. In the areas outside the combat zone (where ius in bello applies) the use of drones is not lawful. In these cases applies enforcement measures law and the drone targeted killings are to be considered “extra-judicial killings”. For these reasons, the practice of the use of drones in different areas of the world not involved in an armed conflict contrast with current international law and compromise the achievement of global security.     


Keywords: drones, ius in bello, ius ad bellum, international law, global security, use of force, self-defense, armed attack.



Content: 1. Global security and use of force: introductive considerations – 2. Use of drones between ius ad bellum and ius in bello – 3. Legality of targeted killings by using drones in relation with international law4. Conclusive remarks



1.   Global security and use of force: introductive considerations


The global security is a concept that concerns primarily the peaceful inter-state relations between the subjects of international law. It regards certainly the preservation of an international balance among all members of the international community in full respect of the principles governing these relations, exactly the sovereign equality and the respect for territorial integrity of the States. Security among international subjects means, first of all, renounce from threat or use of illegitimate force in international relations, in full compliance with art. 2 (4) of the Charter of the United Nations[1]. In this sense, the fundamental text sanctioned an already known and respected principle of international law: the general and absolute prohibition of use of force[2]. Art. 2 (4)[3] of the Charter firmly rejects the use or the threat of force against the political independence or territorial integrity against any State or not in conformity with the Charter itself[4]. The prohibition is absolute and does not admit any exception, beside the case of  being the use of force a countermeasure in event of an armed attack, perpetrated by an aggressor State: this is the case of the individual or collective self-defence provided for in art. 51 of the Charter[5]. The other exceptional circumstance, sanctioned in the Charter, that justifies the use of force is represented in the faculty of the Security Council which, according to the dispositions of the Chapter VII, may authorize such extraordinary act[6].

Outside the legal «perimeter» of the UN Charter dispositions, according to the general international law, use of force is «tolerated» in particular circumstances: fortuitous case, force majeure, distress or approval of the entitled subject[7].

Furthermore, in case Security Council of the UN be paralyzed due to the veto imposed by one (or more) of the permanent Members, blocking in this way its decision-making power on the authorization of the use of force in presence of fulfilled conditions, one or more States, acting on behalf (uti universi) of fundamental interests of the whole International Community, could resort to the use of force against one or more States[8], considered offender(s) of an international norm productive of erga omnes obligations[9]. In this case, the use of force should necessarily meet the required criteria as sanctioned in the UN Charter with regard to Chapter VII, besides the impossibility of the Security Council to authorize these measures due to the veto imposed by the permanent Member.

Lastly, any consideration on the pre-emptive use of force, especially with regard to the usage of drones as military means, should necessarily address the question of the admissibility of such ius ad bellum doctrine. According to an extensive interpretation of art. 51 of the UN Charter[10], the so-called accumulation doctrine rests on the grounds of the equalization of the pre-emptive intervention with the anticipatory one. The customary norm on self-defence, recalled directly in art. 51 of the UN Charter, permits the preventive use of force only in case the armed attack is imminent[11]; therefore, there is no room for reaction to future and hypothetic armed attacks discretionally to be decided and evaluated by the States[12]


2.   Use of drones between ius ad bellum and ius in bello


There is a quite open debate whether drones, as unmanned aerial vehicles, constitute battlefield military weapons and, consequently, their use concerns international law or peacetime police operations. The history of traditional use of drones, as relevant commentators sustain[13], goes back right in the aftermath of second World War[14] but the modern use of these unmanned military weapons became more intense and problematic after the Nineties[15]. United States represents probably the most active Power[16] in using remote means technology during international armed conflicts or facing terroristic threats in several countries[17].

The first element of consideration concerning the use of drones is that, despite their fundamental characteristic of being unmanned, their usage in not expressively prohibited by international law. Obviously, non-military drones or those used for civilian purposes are not a question of concern with regard to international law in general and use of force in particular.

The most distinctive element of (military) drones, besides other means of warfare, resides not only in the fact that they are not physically guided by a human operator (unmanned weapons) but rather in the question of the typology of carried weapons. As practice and experience shows, bombs and missiles are the most common weaponry launched or dropped by drones in combat areas. The use of these kind of weaponries and operations is for sure not governed by law enforcement regime norms but, to the contrary, constitute a clear evidence of connection with international humanitarian law: that is the law applied during armed conflicts. The question whether their use concerns the law enforcement regime (and human rights law) or ius in bello is strictly related to the nature of the weaponry involved and the nature of the operations implicating the use of drones themselves. Although considered a modern instrument of warfare[18], drones are classified among other instruments of belligerent activity. Thus, if used in a context of peacetime operations and without legitimate title, their use implicates an act of force prohibited by international law.

To the contrary, in case of wartime operations, the use of military drones constitutes one of the tolerated methods of warfare, though conditioned by the strict rules of humanitarian regime.  Which means that, the lethal nature of the involved force necessarily requests the application of humanitarian law regime. Use of drones during armed conflicts implicates directly targeted killings of individuals participating (or not) in hostilities. So the distinction of the military lawful targets from the civilian one is a primordial requirement besides the precaution and proportionality principles. Geneva Conventions on ius in bello and related Additional Protocols clearly distinguish between individuals who are directly participating in hostilities and civilians not taking part in the conflict[19]: art. 51 of the Additional Protocol I sanctions the obligation to exclude from armed attack in favor of the second category[20]. As correctly sustained, in international armed conflicts, the principle of distinction is «relatively straightforward to apply»[21] as far as the members of the armed forces of the belligerent Parties are considered legitimate target of capture and/or attack, including lethal force. The difficulties become more consistent in presence of a non-international armed conflict mostly because of the objective nature itself of these kind of conflicts as well as also for the lack of general consensus in the doctrine and case law concerning the status of the members of the non-state armed groups[22]. Considering that almost all the cases where drone military technology is involved concern non-international armed conflicts, the behavior of the most active Powers in using this technology becomes object of reflection in a larger and general scale. The use of drones against civilian objectives could be considered in conformity with humanitarian law regime only if the civilians participate directly in the hostilities[23] or they fulfill the criteria of continuous combat function in a larger context of good faith and reasonable considerations. Probably, the use of drones in non-international armed conflicts, characterized by an asymmetrical nature of belligerence, is of particular «interest» for the State party in the conflict, considering the objective impossibility to face a similar counter-belligerent.

In the same way, the principle of necessity concerns the equilibrium between military exigencies and elements of humanitarian principles. If the objective or the goal of any military action could be reached by the mean of a less lethal measure the principle of necessity takes a primary role in terms of legality under international humanitarian law.

With regard to the principle of proportionality, according to a correct interpretation of the dispositions of art. 51 of the Additional Protocol I to the Geneva Conventions, it is prohibited any attack which may cause excessive advantage in relation to the concrete military target. The debate becomes delicate in case of use of drones where calculations over the proportionality deal with the impossibility of physical contact with the targeted object. Being managed at distance and entirely through computer screens, drones have favored the so-called «Playstation mentality» to killing[24].

However, it is not a question of nature of warfare instrument that renders more or less proportionate the use of drones in armed conflicts: the question concerns rather the transparency and accountability of such operations involving the use of drone technologies[25].


3.    Legality of targeted killings by using drones in relation with international law


The notion of targeted killing regards the intentional and premeditate killing of agents of the enemy in a context of armed conflict[26]. In fact, any targeted killing outside an armed conflict is to be considered a violation of the international norms on the protection of human life sanctioned in all the international instruments in the field of human rights. In some rarely exceptional cases, extrajudicial killings are tolerated only if this is the only, proportionate and necessary mean for the protection of other lifes[27].

The question, however, concerns the possibility involve drones outside armed conflict areas in order to commit extrajudicial killings. Targeted killings during any armed conflict between States or a State and a non-State actor are considered admissible if in accordance with the respective law governing such conflicts. International humanitarian law prevails in case of military operations during situations of armed conflicts and thus, the usage of drones for targeted killings is tolerated if the lethal force involved through their use is directed only against subjects qualified as legitimate fighters or combatants. In particular cases lethal force may be employed against civilians directly participating in belligerent hostilities, losing in this way their neutral status from the moment they engage directly in hostilities[28].  In situations concerning cases of non-international armed conflicts, international human rights rules apply and in these cases lethal force would be tolerated in case of full respect of related criteria.

The question of major concern regards the use of drones with the declared (or not) purpose of targeted killings. In a domestic context of law enforcement policy the question regards the engagement rules determined by the State through national legislation in relation with the use of lethal force by proper authorized agents or organs during particular typologies of police operation. The appropriate law to be applied in these case is the human rights law which imposes very strict rules and requirements to this purpose. Necessity, proportionality and extreme threat may only authorize such a kind of lethal force usage. The use of drones in cases of domestic law enforcement operations is thus less justifiable considering the individual or minor threat represented by the suspected criminal or criminals compared to the enormous and infinite means at disposition of the government authorities in order to face with the isolated problems of domestic criminality.

To the extent of this survey, the targeted killings through the use of drones in situations of inter-State relations, outside situations of armed conflicts among the involved States represent the main challenge. The use of force in international law short of any UN Security Council authorization (art. 2, § 4 of the Charter) or right to self-defence (art. 51 of the Charter) is to be considered a violation of the equal sovereignty of the States. Outside the just mentioned exceptions on the use of force under international law, the use of force (use of drones for targeted killings) may be justified if the territorial States grants express and clear consent for the conduct of such military operations. Military use of force in areas where no international armed conflict is registered, where no right to self-defence is legally claimed or no SC authorization is endorsed asks for explicit consent by the territorial State in order to grant legality to targeted killings.

The biggest problem with the use of drones for the purpose of targeted killings is represented by the fact that in several cases bombs or missiles launched by them cause indiscriminate civilian victims and thus, violate international humanitarian law. The problem surely does not question the admissibility of such war instruments but rather their use in full conformity with humanitarian rules. If any armed conflict has not occurred the use of drones may be justified from reason of self-defence; in cases of conflicts involving at least one non-State party, their use may constitute a clear violation of international norms. For these reasons there is an enormous need for transparency and accountability in cases of use of drones for targeted killings. State practicing targeted killings through drone technology should guaranty the maximum of these both requirements in order to comply, in consideration of the particular nature of these weapons, with international law.


4.    Conclusive remarks


  The achievement of global security is better realized when the members of the International Community fully comply with the rules of ius ad bellum in inter-State relations. Thus, the use of drones in international law, as a form of use of force, should necessarily meet the requested criteria of self-defence or UN Security Council authorization. In these cases apply the Geneva humanitarian regime which imposes severe and strict rules for the conduct of hostile activities, whose main goal aims the reduction of the causalities. The protection of the civilians and other subjects not participating directly in the hostilities is a cornerstone of international humanitarian norms. It is not questioned the use of drones during belligerent operations but rather their use in conformity with the «laws of war». Any disproportionate use of drones during qrmed conflicts constitutes war crimes, punishable according to the provisions of the Geneva Conventions and relative Protocols.

Targeted killings are tolerated in case of express and explicit consent of the territorial State towards such kind of tactics in its territory. When a conflict occur between a State and a non-State actor the use of drones may be lawful only if the territorial State grants proper consent. Outside these cases, the use of remotely piloted aircrafts is severally prohibited causing in this way the international responsibility of the author State for unauthorized use of force in the territory of another State. Except the international responsibility of the State for illegitimate use of force human rights law is also applicable, in consideration of the fact that these kind of operations in time of peace are considered extrajudicial and, thus, arbitrary deprivation of life.     





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