The Defense Department apparently thinks that it may lawfully kill an unlimited number of civilians forced to serve as involuntary human shields in order to achieve even a trivial military advantage. According to the DOD’s recently released Law of War Manual, harm to human shields, no matter how extensive, cannot render an attack unlawfully disproportionate. The Manual draws no distinction between civilians who voluntarily choose to serve as human shields and civilians who are involuntarily forced to serve as human shields. The Manual draws no distinction between civilians who actively shield combatants carrying out an attack and civilians who passively shield military objectives from attack. Finally, the Manual draws no distinction between civilians whose presence creates potential physical obstacles to military operations and civilians whose presence creates potential legal obstacles to military operations. According to the Manual, all of these count for nothing in determining proportionality under international law.
In my view, the DOD’s position on involuntary human shields is both legally and morally indefensible. It is also something of a surprise. As recently as 2013, the US Joint Chiefs of Staff took the view that when civilians are intermingled in the target area or are used as human shields, “[j]oint force targeting … is driven by the principle of proportionality, so that otherwise lawful targets involuntarily shielded with protected civilians may be attacked … provided that the collateral damage is not excessive compared to the concrete and direct military advantage anticipated by the attack.” On this sensible view, civilians are protected by the principle of proportionality whether they find themselves near military targets by chance or by force. If the expected harm to civilians is not justified by the anticipated military advantage, then the attack is disproportionate and therefore unlawful. Unfortunately, the Manual departs from this sensible view.
The Manual appears to strip the proportionality principle of much of its protective power. For many, the paradigm case of disproportionate attack is destroying a residential building and killing its civilian inhabitants to eliminate a single combatant hiding inside or firing from the roof. Yet, according to the Manual, such an attack is not disproportionate at all if the combatant enters the building with the intent to use the civilians as passive, involuntary human shields. According to the Manual, all of these civilians lose their legal protection from excessive incidental harm through no fault of their own. On the DOD’s view, as far as proportionality is concerned, these civilians may as well not exist.
The Manual cites no basis in treaty, custom, or scholarship for its position. Nor could it do so. As is well known, Protocol I to the Geneva Conventions immediately follows its prohibition on the use of human shields with an unequivocal statement that “[a]ny violation of these prohibitions shall not release the Parties to the conflict from their legal obligations with respect to the civilian population.” Yet, according to the Manual, if a defending force violates the prohibition on using civilians as involuntary human shields then the attacking force is, in effect, released from its obligation not to inflict excessive incidental harm on those civilians.
Of course, the United States is not a signatory to Protocol I. However, the United States is bound by customary international law, one principle of which is that international humanitarian law (IHL) applies unconditionally to each party to an armed conflict irrespective of the conduct of opposing parties. If the DOD thinks that unlawful conduct by our adversaries releases us from our obligations under customary international law, it is badly mistaken.
Speaking of customary international law, state practice indicates that, while the presence of human shields does not automatically prohibit an attack, an attacker “must respect the principle of proportionality … even though the defender violates international humanitarian law.” For example, the Israeli Supreme Court holds that when “civilians are forced to serve as ‘human shields’ … the rule is that the harm to the innocent civilians must fulfill, inter alia, the requirements of the principle of proportionality.” In contrast, the Manual cites no state practice supporting the DOD’s position.
As for scholarly opinions, Michael Schmitt describes the position that involuntary shields cannot render an attack disproportionate as an “extreme view” that “occasionally surfaces in discussions” among military lawyers but for which Schmitt finds no legal or logical basis. As Schmitt notes, IHL “evidences scant precedent to support the loss by a civilian of protected status due to the wrongful acts of one of the parties to the conflict.” He observes that the “polar opposite, and better approach [that] treats involuntary shields as civilians entitled to the full benefits of their international humanitarian law protections,” “seems to dominate among international humanitarian law experts.”
In my view, the DOD’s position is not only legally baseless but also morally unintelligible. According to the Manual, an attack that would be disproportionate if some number of civilians is near a target by chance will be proportionate if the same number — or an even greater number — of civilians is forced near the same target by the opposing party. In a recent paper, I suggested that to state this position is to refute it, but perhaps an example will prove helpful:
One Target: You can strike a legitimate military target from the North or from the South. If you strike from the North, then you will kill 10 civilians who are unwittingly passing by. If you strike from the South, then you will kill 20 civilians forced to serve as involuntary human shields.
According to the Manual, if the military advantage anticipated by destroying the target is fairly small then it might be disproportionate to strike from the north, killing 10 civilians, but proportionate to strike from the south, killing 20 civilians. This implication seems absurd. If military advantage cannot justify killing 10 civilians who have done nothing to forfeit their legal rights, then it certainly cannot justify killing 20 civilians who have done nothing to forfeit their legal rights.
If the fact that there is only one target in the previous example is distracting then consider the following variation:
Two Targets: Military targets A and B are weapons caches containing the same number of rifles. 10 civilians are unwittingly passing by target A. 20 civilians are forced to serve as involuntary human shields for target B.
According to the Manual, if the military advantage anticipated by destroying the weapons in each cache is fairly small then it might be disproportionate to strike target A, killing 10 civilians, but proportionate to strike target B, killing 20 civilians. This implication seems equally absurd, and makes the position that generates it seem morally incoherent.
Since the DOD’s position has no obvious basis in law or morality, I expected the DOD to offer strong arguments in its defense. What I found was disappointing.
First, the Manual states that “[t]he party that employs human shields in an attempt to shield military objectives from attack assumes responsibility for their injury.” This statement is either a circular argument or a non sequitur. Of course combatants who use human shields are responsible for the foreseeable harm they occasion. It hardly follows that combatants who kill human shields are not responsible for the foreseeable harm they inflict, particularly when the harm they expect is not justified by the military advantage they anticipate. Perhaps the latter claim can be proven, but certainly it cannot be assumed.
Second, the Manual states that “[i]f the proportionality rule were interpreted to permit the use of human shields to prohibit attacks, such an interpretation would perversely encourage the use of human shields.” This statement suggests that IHL should permit the unlimited killing of involuntary shields so that, in the long run, fewer involuntary shields will be killed. I reject the view that IHL should strip individual civilians of legal protection in hopes of reducing aggregate harm. My reasons need not detain us here, because the DOD’s apparent argument fails on its own, broadly utilitarian terms.
Ordinarily, we deter others by threatening to make them worse off if they engage in certain conduct than if they do not. Yet attacking combatants despite the presence of involuntary shields will not make those combatants any worse off than they would have been without those shields. On the contrary, if defending forces expect additional (say, political) benefits and no additional costs from using involuntary shields then killing these involuntary shields will not deter their use.
Finally, the Manual states that “[i]f the proportionality rule were interpreted to permit the use of human shields to prohibit attacks, such an interpretation would … allow violations by the defending force to increase the legal obligations on the attacking force.” To be clear, defending forces that use human shields do not thereby “increase” the legal obligations on the attacking force but instead trigger the ordinary legal obligation not to inflict excessive incidental harm on civilians. Evidently, defending forces trigger this obligation whenever they locate their personnel and equipment near civilians, whether or not they intend to thereby shield their personnel and equipment from attack.
Perhaps the DOD thinks that it is unfair for defending forces to intentionally trigger the legal obligations of the attacking force, through unlawful conduct, as a means of obtaining tactical advantage. Indeed it is. Perhaps the DOD thinks that attacking forces may deprive defending forces of such unfair advantages by killing involuntary shields without limit. They may not. War, like other parts of life, is often unfair. Killing involuntary shields shifts the unfair burdens imposed on the attacking force, not onto the defending force that imposed them, but onto the latter’s civilian victims. We cannot correct but can only compound the unfairness of war by killing civilians who have done nothing to forfeit their legal rights.
In my view, we should deter the use of civilians as involuntary shields, and annul the unfair advantages gained through their use, by prosecuting those who use them for war crimes. In contrast, we should not, in effect, punish civilians for war crimes committed against them.
In contemporary armed conflict, combatants fight where civilians live. IHL cannot fulfill its purpose of protecting civilians if civilians can lose their legal rights due to the unlawful conduct of others. Now, more than ever, the principle of proportionality must protect civilians and restrain combatants. The DOD’s new Manual represents a significant step in the wrong direction.