An important question raised in a recent post in Just Security is what law governs when a state can resort to military force against a threat from a non-state actor. Professor Eliav Lieblich writes that the  right to life and its exception that allows deprivation of life in self-defense and defense of others fills this legal void. While the right to life is relevant, I strongly disagree with his analysis on the relevance of the right to personal self-defense.  A different approach better answers the question of what law applies—and with fewer costs to the integrity of the human rights system.

Under international law, the human right to life tightly limits the use of lethal force to contain threats to law and order. In particular, state security forces may only use deliberately lethal force (“shooting to kill”) in law enforcement activities when it is absolutely necessary to defend themselves or others against a threat of imminent death or serious injury. As I lay out in my forthcoming book on human rights and personal self-defense, this is one manifestation of the right to personal self-defense, which constitutes a general principle of law recognized by nations. And here’s the important point for Just Security readers: That right is distinct—and should be kept distinct—from a State’s right to defend itself against external threats under Article 51 of the UN Charter.

The standards for state use of lethal force become far more permissive during hostilities in a non-international armed conflict, because international humanitarian law applies alongside human rights law (with both bodies of law shaping each other’s interpretation). This raises the conundrum whether a government can simply escalate an armed confrontation with violent non-state actors from law enforcement action to a non-international armed conflict with the result that its security forces can then rely on the more permissive hostilities paradigm to use force. To say the least, this would entail a perverse incentive: the more violence a government de facto uses, the more violence it is de jure entitled to use.

It is worth keeping in mind how much of a difference the switch to the hostilities paradigm makes for the targets of state force and for innocent bystanders (at that stage known as civilians). As opposed to self-defense, the question of who shot first is not relevant during hostilities; it matters whether the target is a direct participant in the armed conflict or a protected civilian. Whereas lethal force in law enforcement must be carefully minimized, IHL presumes the necessity of immediately engaging the enemy with lethal force (although there is increasing support for the view that this presumption is overcome where a non-state fighter can be safely captured). As long as all feasible precautions are taken, even the foreseeable, yet unavoidable killing of some civilians can be proportional in armed conflict. Conversely, any law enforcement operations that factor in the certain death of innocent bystanders as “collateral damage” are prohibited.

Lieblich correctly establishes that the escalation conundrum is rooted in the (perceived) absence of a jus ad bellum for non-international armed conflict that would determine “whether the [state’s] first resort to hostilities was lawful.”

Traditionally, international law has indeed been neutral on rebellions and insurgencies; neither prohibiting them, nor prohibiting states from suppressing them—regardless of the cause pursued by the rebels. Yet, human rights have long been chipping away at this neutrality principle in different ways. Participants in rebellions against forcible denials of the (human) right to self-determination have been given combatant status under the First Geneva Protocol, while support for the government fighting them has been outlawed. There is also increasing support for the view that the violent overthrow of a democratically elected, human rights abiding government must not be recognized.

However, human rights have not stopped there. The right to life establishes even more comprehensive restraints on the resort to military force, which could be considered a rudimentary “internal jus ad bellum.” I agree with Lieblich on this point, but disagree with key elements of his ensuing analysis, in particular regarding the role of the right to personal self-defense.

Lieblich suggests that the right to life prohibits the state from first resort to hostilities, unless it acts in self-defense or defense of others, so that “if a state decides to resort to hostilities in absence of a threat to life or limb that is comparable in its scale and effects to the threats that emanate from armed hostilities, then the ensuing killings could be considered arbitrary deprivations of life.” In doing so, he extrapolates from standards applicable to the use of defensive force in law enforcement, as laid down notably in Art 2 (2) (a) of the European Convention on Human Rights. He argues that if these standards “govern a single decision to resort to lethal force by a police officer or a police unit, there is no reason to exclude from their purview much broader decisions on force, e.g. by military means.”

The extrapolation argument is highly problematic, because police officers are allowed to use lethal force only within the tightly restricted boundaries of the law enforcement paradigm. They are not allowed to go to war against their population using military means, for example. This is not a valid case of the greater power includes the lesser (a maiore ad minus). Instead, it is an attempt to derive greater powers out of lesser ones (a minori ad maius). At a practical level, any attempt to justify resort to military hostilities with reference to exceptions emanating from the law enforcement paradigm will only invite confusion among practitioners and ultimately erode the rules applicable to law enforcement by infusing them with the armed hostilities paradigm.

Lieblich’s broader point that a state may resort to military hostilities if confronted with a threat to life or limb that is comparable to the threats that emanate from armed hostilities is valid. However, this argument can be condensed to the principle that a state may respond with military means where a non-state actor uses military force first. It is after all hard to imagine physical threats comparable to armed hostilities that do not themselves cross the threshold into armed conflict.

One does not have to invoke the self-defense exception to the right to life to come to this conclusion. International human rights law helpfully sets out a separate and sufficient ground. Importantly, Article 2 (2) (c) of the European Convention on Human Rights allows for deprivation of life where absolutely necessary to lawfully quell an “insurrection” (i.e. non-state force using military means). The enumerated exceptions set out by Art. 2 of the European Convention are generally also read into the right to life under Art. 6 ICCPR and customary international law (see e.g. here, para. 50).

The insurrection exception imposes jus ad bellum and jus in bello requirements on the state. To start with, there must be non-state military force that is ongoing or at least imminent. A future or remote threat of such force is not enough. A state must not wage a preemptive armed conflict against members of its own population (or, for that matter, foreign populations given that the right to life also applies to transnational use of force). It is worth noting that weaving the personal self-defense exception into the analysis, as Lieblich proposes to do, would not call this prohibition of preemptive armed conflict into question, but only strengthens the argument, because there is wide consensus among U.N. and regional human rights mechanisms that self-defense may be exercised only against ongoing or imminent attacks, but not future threats (see e.g. here [para. 35], here [para. 120], here [para. 67] and here [para. 117]).

Likewise, a military response cannot be justified with reference to a military threat that no longer exists. State forces must cease military action and move back into law enforcement mode once the non-state actor has been reduced to a law enforcement challenge. The state forces may not remain in shoot to kill mode until the last member of what was once a military threat is eliminated. The upshot is that this area of the law defines when resort to force may begin and when it must end.

Secondly, military action may be taken only when absolutely necessary. There may be situations where the non-state military challenge is so inept that it can be contained by law enforcement means and there is no need for an armed conflict-type of response, with all the additional risks for the rights to life that this entails, especially for innocent bystanders.

Thirdly, the state must “lawfully” quell any military challenges mounted against it. First and foremost, this requirement has a jus in bello dimension.  The state must only use lawful means that are in line with IHL and human rights. But there is arguably also a jus ad bellum dimension, and this is where the right to personal self-defense finds its proper place in the analysis. Whether the non-state actor started the armed conflict cannot be determinative alone. One also needs to examine whether the non-state actor’s initial resort to military means was not exceptionally justified as an exercise of self-defense as a last resort against serious human rights violations. Not surprisingly, state practice has not yet endorsed such a right to challenge state authority by military means. IHL does allow civilians to defend themselves with non-military means against atrocities by the state without such civilians losing their protected status. Since international law recognizes their non-military resistance as legitimate self-defense, they must also not be arrested and prosecuted for it.

However, once their resistance becomes so organized and intense that they must be seen as a participant in armed conflict, they lose their protection as civilians, with the consequence that they could be targeted and prosecuted based on their armed resistance activities. As I argue in my book, this status quo is not satisfactory. A case can be made for recognition of a narrowly drawn right to militarily organized resistance against mass atrocities (genocide, crimes against humanity and war crimes on a massive scale) that flows from the right to life, the human right to an effective remedy for human rights violations, and the right to personal self-defense as a general principle of law. As the international community has assumed the responsibility to protect victims of mass atrocities, including by using force as the ultima ratio and with Security Council authorization, it should also afford the victims the right to protect themselves. Incidentally, a narrowly tailored right to resist mass atrocities would also serve to distinguish the rare cases of legitimate resistance movements from the many rebels without a cause, while current state practice offers no criteria to do so. The important point here is that if the non-state actor has a right to militarily organized resistance, it may qualify or override the state’s right to resort to military force in response.

Let me conclude by underlining that everything said above also holds for transnational law enforcement or transnational military operations against non-state actors since the right to life under the ICCPR and customary law applies extraterritorially where states exercise jurisdiction by projecting force beyond their borders. For such operations an additional layer of jus ad bellum has to be satisfied to justify the infringement of sovereignty that such operations might entail. This justification can flow from the consent of the territorial state concerned and it is now also accepted by many that an armed attack by a non-state actor situated abroad may give raise to the right to self-defense under Article 51 of the UN Charter. However, as noted above, this right to state self-defense is distinct from the right to personal self-defense. The two have distinct justificatory purposes: The former justifies infringements of sovereignty whereas the latter justifies infringements of individual human rights. Unfortunately, certain policy statements have blurred both concepts where they claim that extraterritorial military operations against non-state actors can be justified with reference to either self-defense or IHL. In reality, such operations need to comply with both Art. 51 of the UN Charter and IHL – and, as explained, the right to life requires that the non-state actor was first to cross the line into military conflict before the state may do so.