Contemporary armed conflicts have increasingly been accompanied by belligerents’ calls for civilians to support their military efforts. This article investigates the legal consequences of civilians taking up arms provided by or with the tacit support of the State. It first looks at the implications of civilian involvement from the perspective of a State's international humanitarian law (IHL) and international human rights law obligations, focusing on removing civilians from the vicinity of hostilities, informing and training civilians on the implications of directly participating in hostilities, and respecting and ensuring respect for the law. It then demonstrates that the broader fabric of public international law is tested when civilians are encouraged to engage in hostilities, through a close analysis of the challenge of attributing civilian acts to the State. The article closes with practical recommendations for States to ensure that they uphold their humanitarian and human rights obligations, and to render the law of international responsibility effective when civilians commit systemic violations of IHL.

This article argues that the growing involvement of civilians in activities on the digital battlefield during armed conflicts puts individuals at risk of harm and contributes to the erosion of the principle of distinction, a cornerstone of international humanitarian law (IHL). The article begins by outlining the ongoing trend of civilianization of the digital battlefield and puts forward brief scenarios to illustrate it. It then examines the narrow circumstances under which such forms of civilian involvement may qualify as direct participation in hostilities under IHL, and discusses what this means for the individuals concerned, particularly from the perspective of their loss of protection under the law. The analysis shows that certain types of State conduct which put civilians in harm's way by inducing them to directly participate in hostilities may constitute standalone violations of IHL and human rights law obligations. Beyond these specific prescriptions, the encouragement of civilian involvement undermines the principle of distinction, with dangerous ripple effects on the interpretation of those rules of IHL that flow from it. Accordingly, the article concludes that States should act to reverse the trend of civilianization of the digital battlefield and refrain as much as possible from involving civilians in the conduct of cyber hostilities.

Endless armed conflicts against terrorist groups put civilian populations at risk. Since France has been involved in the Sahel from 2013 onwards, transnational non-international armed conflicts (NIACs) of extended geographical and temporal scope against groups designated as terrorists are not a US exception anymore. NIACs against terrorist groups, conducted not only by the United States but also by France, persist and have been reconfigured around threat anticipation. How can anticipatory warfare be best constrained? This article argues that it can be best done through more constraining rules regulating target selection in NIACs and, in particular, by redefining the notion of continuous combat function (CCF). Many elements explored in this article indicate that the United States and France select targets that they pre-designate as terrorists, before these targets are engaged in hostilities. Instead of responding to the observed participation of these individuals in hostilities, strikes are based on contextual and behavioural elements ahead or outside of such moments. This paper argues that when war consists of threat anticipation, it becomes very extensive and particularly risky for civilians. Furthermore, recent State practice in the counterterrorism context reveals the pitfalls of the notions of direct participation in hostilities and CCF as defined in the 2009 International Committee of the Red Cross Interpretive Guidance. Outside this context, the interpretations proposed in the Interpretive Guidance might seem sufficient to constrain target selection processes and to protect civilian populations. However, when applied to armed conflicts that are driven by threat anticipation, the pitfalls of these interpretations emerge. I formulate a critique of these interpretations as being partly responsible for anticipatory warfare and propose an alternative theory for the CCF test.

This article provides a legal analysis of the largely uncharted notion of “acts harmful to the enemy” under international humanitarian law, which reconciles the humanitarian need to grant special protection to medical services (medical personnel, units and transports) in the interests of the wounded and sick with the military necessity to remove it when acts are committed contrary to good faith and for hostile purposes or with effects which harm the adverse party. The meaning of the notion is clarified by primarily looking into the legality of an attack against land-based medical services by the aggrieved party to the conflict as a consequence of harmful acts. It concludes with specific recommendations on how to interpret the law governing such an attack, considered prima facie lawful, on a hospital.

This paper focuses on the “continuous combat function” concept and proposes to extend its application. First, the article will demonstrate that the continuous combat function concept should be extended to certain members of organized armed groups in cases where those groups do not belong to any of the parties to an international armed conflict and whose actions do not reach the level of intensity required for a separate non-international armed conflict (NIAC) to exist. Secondly, the paper will look at the extension of this concept in order to determine individual membership in State armed forces in the context of a NIAC, while arguing that the notion of “armed forces” should be interpreted differently depending of the nature of the conflict, be it international or non-international.

The fact that children are drawn to join the ranks of armed forces or non-state armed groups is a scourge that persists despite concerted efforts to eradicate the practice. No facet of this reality is perhaps more shocking than children’s direct participation in hostility, in that it raises the spectre of combatants directly targeting children. International humanitarian law has been largely silent on this specific aspect of child soldiering, leaving armed forces to improvise their stance when confronted with child soldiers on the battlefield. The Canadian Armed Forces in 2017 adopted what is said to be the first official military doctrine on child soldiers. This article analyzes this doctrine in light of the regulation of the use of force against child soldiers under international humanitarian law. It assesses whether children can ever be full-fledge combatants, when they can be considered civilians directly participating in hostilities, and, if children can be directly targeted, what limits humanitarian law imposes on the means and measures of war employed against them.

This article provides a holistic examination of the international legal frameworks which regulate targeted killings by drones. The article argues that for a particular drone strike to be lawful, it must satisfy the legal requirements under all applicable international legal regimes, namely: the law regulating the use of force (ius ad bellum); international humanitarian law and international human rights law. It is argued that the legality of a drone strike under the ius ad bellum does not preclude the wrongfulness of that strike under international humanitarian law or international human rights law, and that since those latter obligations are owed to individuals, one State cannot consent to their violation by another State. The article considers the important legal challenges that the use of armed drones poses under each of the three legal frameworks mentioned above. It considers the law relating to the use of force by States against non-State groups abroad. This part examines the principles of self-defence and consent, in so far as they may be relied upon to justify targeted killings abroad. The article then turns to some of the key controversies in the application of international humanitarian law to drone strikes. It examines the threshold for non-international armed conflicts, the possibility of a global non-international armed conflict and the question of who may be targeted in a non-international armed conflict. The final substantive section of the article considers the nature and application of the right to life in armed conflict, as well as the extraterritorial application of that right particularly in territory not controlled by the State conducting the strike.

Despite widespread State acceptance of the international law governing military use of force across the spectrum of operations, the humanitarian reality in today's armed conflicts and other situations of violence worldwide is troubling. The structure and incentives of armed forces dictate the need to more systematically integrate that law into operational practice. However, treaty and customary international law is not easily translated into coherent operational guidance and rules of engagement (RoE), a problem that is exacerbated by differences of language and perspective between the armed forces and neutral humanitarian actors with a stake in the law's implementation. The author examines the operative language of RoE with a view to facilitating the work of accurately integrating relevant law of armed conflict and human rights law norms. The analysis highlights three crucial debates surrounding the use of military force and their practical consequences for operations: the dividing line between the conduct of hostilities and law enforcement frameworks, the definition of membership in an organized armed group for the purpose of lethal targeting, and the debate surrounding civilian direct participation in hostilities and the consequent loss of protection against direct attack.

The use of “drones” has grown exponentially over the past decade, giving rise to a host of legal and other issues. Internationally, it is the utilization of armed drones by States for the extraterritorial targeting of persons that has generated significant debate. This article attempts to outline some aspects of the relevant legal framework, with a focus on the international law applicable to drone strikes in situations of armed conflict. It briefly addresses the jus ad bellum and then centres on the jus in bello, addressing, in turn, questions related to when there is an armed conflict, what the rules on targeting are, who may be targeted and where persons may be targeted.

Armed drones pose a major threat to the general prohibition on the inter-state use of force and to respect for human rights. On the battlefield, in a situation of armed conflict, the use of armed drones may be able to satisfy the fundamental international humanitarian law rules of distinction and proportionality (although attributing international criminal responsibility for their unlawful use may prove a significant challenge). Away from the battlefield, the use of drone strikes will often amount to a violation of fundamental human rights. Greater clarity on the applicable legal regime along with restraints to prevent the further proliferation of drone technology are urgently needed.

The killing of Osama bin Laden by US Special Forces on 2 May 2011 raises several questions of international law with regard to the legality of this particular operation and the permissibility of targeted killings of international terrorists in general. In this article it will be argued, on the basis of an analysis of the applicable international law, that the killing of bin Laden cannot be justified under international humanitarian law because there is no armed conflict between the United States and Al Qaeda. Even if one were to assume the existence of such an armed conflict, bin Laden's killing would only have been lawful if Al Qaeda were to be considered an organised armed group within the meaning of international humanitarian law and bin Laden could have been killed qua membership of this group. Otherwise, his killing could only have been lawful if he was (still) taking a direct part in hostilities. In any case, in the absence of an armed conflict, under the applicable legal regime of peacetime, the killing could only be justified in a situation of self-defence or an immediate danger for others. As this situation apparently did not exist, the killing of bin Laden amounted to an extrajudicial execution. On another note, the operation may also have violated international law by failing to respect Pakistan's territorial sovereignty. Ultimately, this depends on the recognition of a (pre-emptive) right to self-defence under Article 51 of the UN Charter, in particular taking into account the immediacy criterion.

Section IX of the ICRC Interpretive Guidance on Direct Participation in Hostilities asserts: ‘In addition to the restraints imposed by international humanitarian law on specific means and methods of warfare, and without prejudice to further restrictions that may arise under other applicable branches of international law, the kind and degree of force which is permissible against persons not entitled to protection against direct attack must not exceed what is actually necessary to accomplish a legitimate military purpose in the prevailing circumstances’. The present article scrutinises arguments that have been, or can be, advanced in favour of and against a ‘least harmful means’ requirement for the use of force in situations of armed conflict as suggested in Section IX. The principal aim of the article is to examine the question whether such an additional proportionality requirement forms part of the applicable international lex lata.

The ICRC, following extended discussions with a large group of experts, has adopted and issued a non-legally binding document entitled ‘Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law’ consisting of ten recommendations and about fifty pages of related commentary. The discussion process which preceded production of the Interpretive Guidance was contentious and no consensus was reached on the issue of Direct Participation in Hostilities. As the result, the ICRC, as it was entitled to do, issued its own interpretation of the applicable law. The author of this article, who was involved in all of the expert meetings, reviews and comments on the Interpretive Guidance and attempts to make an assessment of its general viability and of its acceptability to the wider IHL community.

The Israeli official policy of targeted killing has often been a subject of controversy and criticism. Although still applied by the state of Israel, this cruel practice was recently limited in a courageous decision handed down by the Israeli Supreme Court. The new restrictions on targeted killing represent an important step towards its criminalization. Despite this, the Court's interpretation of the international humanitarian law requirements is still too broad and there is a need for more restrictive safeguards. In addition, the current uncertainties of this field of law, replicated in the decision, exacerbate the problem further. The main difficulty, however, lies in the theoretical assumption that targeted killing is legal. This article proposes instead to view targeted killing as an exception to the presumption of protection of the civilian population. The authors review the recent trends in international humanitarian law in order to assess the impact of the Court's reasoning. Although this landmark case represents an important breakthrough, it will certainly not be the last word on targeted killing.

A central concept found in the 1907 Hague Regulations Respecting the Laws and Customs of War on Land is the notion of ‘belligerents’. The formal status of ‘belligerents’ or, in more modern terms, ‘combatants’, is limited to international armed conflicts. One of the crucial functions that the status fulfils relates to distinguishing those who are legitimate objects of attack from those who enjoy protection. Combatants are legitimate targets, while civilians are not, unless and for such time as they directly participate in hostilities. Civilians are defined as all those who are not combatants. Because the formal status of ‘combatant’ is limited to international armed conflicts, the principle of distinction cannot be conceptualized in the same way in non-international armed conflicts. Who, then, may be targeted in non-international armed conflicts and under what conditions and who is conversely immune from being made the object of attack and enjoys protection against the dangers arising from military operations by virtue of the status of ‘civilian’? This article argues that, in principle, members of armed forces of both state and non-state parties to a non-international armed conflict are legitimate targets and all those who are not such members are to be considered civilians. However, the practical operationalisation of the principle of distinction in this way faces a number of difficulties. Due to the variety and changing nature of organised armed groups, a more differentiated approach is required in striking a reasonable balance between military considerations and humanitarian concerns.