Ukraine Symposium – Reprisals in International Humanitarian Law

by | Mar 6, 2023


The scale and scope of international humanitarian law (IHL) violations by Russian and associated forces during the conflict in Ukraine are staggering. Yet, Russia has justified some of its operations as retaliatory responses to alleged Ukrainian misdeeds. For instance, concerning its unlawful attacks on Ukraine’s power infrastructure (see my analysis here and here), President Putin quipped, “Yes, we are doing this. But who started it? . . . Who struck the Crimean Bridge? Who blew up the power lines of the Kursk nuclear power station?” He warned, “To leave such acts without a response is simply impossible.” Claims that the attacks on Ukrainian cities were launched as retaliation for the Kerch bridge attack (see Milanovic & Schmitt) and other Ukrainian strikes have drawn praise from Russia’s hardliners.

The false narrative that Russian operations are justified as revenge for Ukrainian abuses has seeped down to the tactical level. Recall the horrific April 2022 Russian attack on the Kramatorsk train station, which was being used by civilians fleeing the hostilities. Fifty-eight people died, and more than a hundred were wounded. Investigation revealed that the cluster bomb used in the attack had been spray-painted with the message “payback for our children.”

At times, Russia’s allegedly retaliatory attacks have been directed at members of Ukraine’s armed forces. For instance, in January 2023, the Russian Defense Ministry claimed a missile strike that supposedly killed 600 Ukrainian soldiers in Kramatorsk was a revenge attack for a New Year’s Day Ukrainian attack on a facility housing Russian troops in the so-called Donetsk People’s Republic (on Ukraine’s response see here). Indeed, even Russia’s current offensive campaign has been labeled “big revenge” for Ukrainian resistance to the February 2022 invasion.

This post examines when retaliatory strikes, including those that might violate IHL, are lawful. In IHL terms, this is the law of reprisal, a fraught topic on which the United States and some of its closest allies part legal ways. Discussion begins with a brief mention of the history of reprisals. The post then lays out the general conditions applicable to reprisals that are not prohibited by treaty or customary law. A catalog of treaty prohibitions on reprisals follows; of particular importance are those contained in Additional Protocol I to the 1949 Geneva Conventions, which binds both Parties to the conflict in Ukraine. The post concludes with a discussion of the customary status of the reprisal rules, a subject of great importance to the United States and other non-Parties to the Protocol.

History of the Prohibition on Reprisals

As a general matter, “tu quoque” (you too) arguments, by which the enemy’s IHL violation justifies one’s own, have no place in international humanitarian or international criminal law (the principle of non-reciprocity). Moreover, a material breach of an IHL treaty obligation does not excuse termination or suspension of the treaty in question (ICTY, 2000, Kupreškić, ¶¶ 511, 515-20; Vienna Convention on the Law of Treaties, art. 60(5)). Yet, in one situation, IHL countenances violations of its rules based on the enemy’s violation, albeit for a single purpose and with strict limitations – qualification as a reprisal.

A reprisal is an act or omission that would otherwise violate IHL, like the prohibition on attacking civilian objects. Still, it is permitted in order to compel the enemy to desist in its own unlawful conduct (see DoD Law of War Manual, § 18.18.1). The acceptance of reprisal as a self-help tool is a historical response to the absence of a reliable and timely IHL enforcement mechanism. In theory, the availability of reprisals will both deter future IHL violations and compel the termination of those that are underway. However, as reprisals involve an intentional breach of an IHL prohibition or obligation by the victim State, strict conditions are imposed on them.

The 1863 Lieber Code highlighted both points.

Art. 27. The law of war can no more wholly dispense with retaliation than can the law of nations, of which it is a branch. Yet civilized nations acknowledge retaliation as the sternest feature of war. A reckless enemy often leaves to his opponent no other means of securing himself against the repetition of barbarous outrage.

Art. 28. Retaliation will, therefore, never be resorted to as a measure of mere revenge, but only as a means of protective retribution, and moreover, cautiously and unavoidably; that is to say, retaliation shall only be resorted to after careful inquiry into the real occurrence, and the character of the misdeeds that may demand retribution.

Unjust or inconsiderate retaliation removes the belligerents farther and farther from the mitigating rules of regular war, and by rapid steps leads them nearer to the internecine wars of savages.

Accordingly, for example, reprisals against Confederate soldiers for murdering and enslaving Union soldiers were authorized by the United States during the Civil War (DoD Law of War Manual, § 18.18.1). The permissibility of reprisals was later recognized in Article 86 of the non-binding 1880 Brussels Manual. Indeed, the various Hague Conventions of 1899 and 1907 are silent on the issue, thereby implicitly acknowledging their acceptability in certain situations. And the utility of reprisals was even conceded in the post-Second World War trials of war criminals, in which those accused tried to justify their horrific abuses on that basis. For instance, the French Permanent Military Tribunal at Dijon observed, “It was admitted that ‘reprisals between belligerents cannot be dispensed with, for the effect of their use and of the fear of their being used cannot be denied.’ It would thus appear that, in the present stage of its growth, international law still recognises reprisals, admittedly within certain conditions and limitations.” (Trial of Franz Holstein and Others at 28).

But over time, States began to impose prohibitions and limitations on reprisals. For example, Article 2 of the 1929 Geneva Convention on Prisoners of War prohibited reprisals against POWs. Two decades later, all four of the 1949 Geneva Conventions included prohibitions on reprisals, as did the 1977 Additional Protocol I to those instruments (see discussion below).

Reprisals Generally

General international law countenances certain violations by a State in the face of violations by another State. The law of State responsibility, for instance, allows for non-forcible and proportionate countermeasures (formerly known as peacetime reprisals), which are acts or omissions that would be unlawful but for the fact that they are designed to directly or indirectly compel another State to desist in its own unlawful conduct or secure any reparations that may be due (Articles on State Responsibility, arts. 22, 49). The wartime analog to a countermeasure is a reprisal calculated to cause the enemy to cease an IHL violation.

The IHL rules permitting reprisals apply only during international armed conflict. They do not govern responses to international law violations in non-international armed conflicts (see discussion below) or peacetime. Nor are reprisals available during an international armed conflict in response to breaches of rules other than those found in IHL.

For the sake of clarity, a lawful action taken in retaliation for enemy operations is not a reprisal. Thus, for example, an operation targeting a valid military objective – including combatants, members of organized armed groups, and civilians directly participating in hostilities – that complies with IHL rules such as proportionality and the requirement to take precautions in attack is not a reprisal. Relatedly, responses to the enemy’s lawful military operations cannot qualify as reprisals. Accordingly, the Russian operations against Ukrainian troops purportedly in response to the New Year’s Day attack would not need to qualify as a reprisal to be lawful, for enemy troops, so long as not hors de combat, are targetable. Similarly, Russia’s “big revenge” cannot be styled as a reprisal because it is neither in response to Ukrainian IHL violations nor per se unlawful under IHL (although individual aspects of the operation may be and it surely is a continuation of the unlawful use of force against Ukraine under the jus ad bellum).

Widespread agreement exists that certain conditions attach to reprisals. Most importantly, the sole permissible purpose of a reprisal is to compel the enemy into compliance with IHL (DoD Law of War Manual, § In particular, revenge or punishment cannot justify reprisal, an important point with respect to the Russian attacks. This limitation on purpose also means that IHL violations unlikely to have that effect cannot qualify as reprisals. It also necessarily implies that reprisals cannot be launched in anticipation of enemy violations and cannot occur in the absence of a reasonable belief that a violation(s) that has taken place is but one in a related series of violations, as is the case with Russian attacks against civilians, civilian objects, and other protected persons and objects. As soon as the enemy complies with IHL, the right to engage in reprisals expires (Kupreškić, ¶ 535).

Considering the coalition operations that characterize much of modern warfare, the purpose limitation raises the question of which party to the conflict is entitled to engage in reprisal and against which of its adversaries. Professor Yoram Dinstein suggests that any member of a coalition or alliance may engage in a reprisal against an enemy violating IHL “if such an action is perceived to be an effective deterrence in the common interest of the allies” (Conduct of Hostilities, 4th ed., at 341). This is a sensible conclusion for several reasons, not the least of which is that the State that has been the target of the enemy IHL violations may lack the means to effectively conduct a reprisal (e.g., air assets capable of penetrating enemy air space or artillery systems with the necessary range).

However, Professor Dinstein goes on to suggest that reprisals may be conducted against an ally of the offending State. While acknowledging historical practice supporting the position (Cysne arbitration and practice in the Second World War), the International Committee of the Red Cross (ICRC) is of the view that “resort to such reprisals is no longer valid” (Customary IHL Study, Rule 145 commentary).  It points to the limitation of countermeasures to the responsible State and to numerous military manuals that either disallow reprisals against other than the offending State or define reprisals as actions taken against an offending State. In my view, support for the ICRC’s argument is somewhat weak as a strict matter of law, especially in light of most States’ failure to take a position on point. That said, given the general trend against reprisals outlined below, it is the approach likely to prevail over time.

There is universal consensus, however, that neutral States may neither engage in reprisals on behalf of the victim State nor be the target of them by that State. This was the issue in the 1930 Cysne arbitration, which held that Germany’s destruction of a Portuguese (neutral) vessel as reprisal for the United Kingdom’s violation of international law was unlawful (p. 1056).

A second condition is that a reprisal must be the last resort of the victim State, that is, resort to an otherwise unlawful act or omission is the only measure available to put an end to the enemy’s violation(s). For instance, the DoD Law of War Manual cites the possibility of “protests and demands, retorsion, or reasonable notice of the threat to use reprisals before resorting to reprisals” (§ Indeed, a warning of some sort is required to establish that the reprisal is the last resort (1928 Naulilaa arbitration at 1025-26; Kupreškić, ¶ 535). As indicated by the use of “or” in the DoD Law of War Manual, the requirement is less a formal warning than one means of ensuring that the offending State understands it faces reprisals unless it desists. This point is also indicated in the Manual’s requirement to make public the reprisal to dissuade the enemy from additional IHL violations (§

Further, a reprisal must be proportionate to the enemy’s violation. This has long been a cornerstone requirement in the law governing reprisals (1880 Oxford Manual, art. 86; Naulilaa arbitration, 1996 Nuclear Weapons Advisory Opinion, art. 46; Kupreškić, ¶ 535). Proportionality, however, does not require reprisals to be in-kind with respect to the IHL rule that is being violated, the means used to violate it, or the nature of the violation. Instead, as noted in the DoD Law of War Manual, proportionality is a question of harm caused by the enemy’s breach: “A reprisal should not be unreasonable or excessive compared to the adversary’s violation” (§

Of course, unreasonableness and excessiveness are highly subjective thresholds. Sometimes, the disproportionate nature of operations is evident, as in the case of the German Einsatzgruppen killing 2,100 Jews in alleged reprisal for the killing of 21 German soldiers (U.S. v. Ohlendorf et al., U.S. Military Tribunal, 1949, at 493-94). However, given the admissibility of reprisals that are not in-kind, and the difficulty in quantifying most forms of harm, the DoD approach is operationally sound. As its Law of War Manual notes in explaining the term “excessive” in the context of the proportionality rule, the determination “involves both professional military judgments as well as moral and ethical judgments” (§ 5.12.3). To illustrate, even if Ukraine had violated IHL, the scale and scope of the Russian responses preclude them from qualifying as lawful reprisals.

Finally, only those at the highest levels of government are entitled to authorize reprisals. The 1880 Oxford Manual, for instance, required a decision by the “commander in chief” (art. 86). In Kupreškić, the International Criminal Tribunal for the Former Yugoslavia (ICTY) explained that reprisals “may be taken only after a decision to this effect has been made at the highest political or military level; in other words they may not be decided by local commanders” (¶ 535). The DoD Law of War Manual similarly states, “authority to conduct reprisal is generally held at the national level. Service members and units are not to take reprisal action on their own initiative” (§, while the United Kingdom’s Manual Law of Armed Conflict provides, “commanders and commanders-in-chief are not to take reprisal action on their own initiative. Requests for authority to take reprisal action must be submitted to the Ministry of Defence and require clearance at Cabinet level” (§ 16.19.2). Thus, to be lawful as reprisals, the Russian actions would need to have been approved by President Putin, Minister of Defence General Sergei Shioigu, or someone else at the highest level of government.

Specific Treaty Law Prohibitions

The four 1949 Geneva Conventions, which bind States Party like Ukraine and Russia, prohibit reprisals against the following specified protected persons and objects. The prohibitions unquestionably reflect customary law that is binding on all States.

1. Personnel, buildings, or equipment protected by Geneva Convention I on the Wounded and Sick in the Field (art. 46). These include the wounded and sick (art. 13), the dead (art. 15), medical and religious personnel attached to the armed forces (art. 24), personnel of aid societies (art. 26), and medical personnel of societies of neutral countries (art. 27). Protected property includes fixed medical establishments and mobile medical units (arts. 19, 33, and 34); hospital ships (art. 20); and medical transport, including aircraft (arts. 35 and 36).

2. Personnel, vessels, or equipment protected by Geneva Convention II on the Wounded, Sick, and Shipwrecked at Sea (art. 47). These include the wounded, sick, and shipwrecked (arts. 12 and 13); the dead (art. 18); religious, medical and hospital personnel of hospital ships and their crews (art. 36); and religious, medical and hospital personnel assigned to the medical or spiritual care of the persons designated in Articles 12 and 13 (art. 37). Protected objects include hospital ships (arts. 22, 224, 25, 33); neutral vessels assisting the rescue effort (art. 21); coastal, rescue craft, and their coastal installations (art. 27); sick bays (art. 28); and medical transport, including aircraft (arts. 38 and 39).

3. Prisoners of War (GC III, 13).

4. Persons and their property protected under Geneva Convention IV on Civilians (art. 33). This prohibition applies to all protected persons, whether in occupied territory or the territory of a party to the conflict (see 1958 ICRC Commentary). On the subject of protected persons, see Articles of War, Mačák and Orkin)

Additional Protocol I develops the prohibition on reprisals in Article 20 for Parties to the instrument (including Russia and Ukraine) by prohibiting reprisals against any persons or objects protected by its Part II, which deals with the wounded, sick, shipwrecked, medical personnel, religious personnel, and medical units. It is, in part a gap-filler for the failure of the 1949 Geneva Conventions to encompass certain categories, such as civilian wounded and sick and civilian medical facilities and transports. Other provisions of the instrument bar reprisals against civilians (art. 51(6)), civilian objects (art. 52(1)), cultural objects and places of worship (art. 53(c)); objects indispensable to the survival of the civilian population (art. 54); the natural environment (art. 55); and works and installation containing dangerous forces (art. 56 – dams, dykes, and nuclear electrical generating stations). The U.S. Army/Marine Corps Commander’s Handbook on the Law of Land Warfare emphasizes that buildings and materiel used for civil defense purposes are civilian objects and, therefore, cannot be the subject of reprisal by Parties to Additional Protocol I (FM 6-27/MCTP 11-10C, ¶ 5-60).

Interestingly, the United Kingdom, which is a Party, issued a reservation to the Additional Protocol I prohibitions, noting, “[i]f an adverse party against which the United Kingdom is engaged makes serious and deliberate attacks, in violation of Article 51 or Article 52 against the civilian population or civilians or against civilian objects, or, in violation of Articles 53, 54 and 55, on objects or items protected by those Articles, the United Kingdom will regard itself as entitled to take measures otherwise prohibited by the Articles in question….” It went on to acknowledge that such a response, which would clearly be a reprisal action, is subject to the various conditions described above.

Certain other treaty law rules prohibit reprisals. Article 4(4) of the 1954 Convention for the Protection of Cultural Property prohibits them against cultural property “of great importance to the cultural heritage of a people.” Article 3(7) of the 1996 Protocol II to the Convention on Certain Conventional Weapons bars the reprisal use of mines, booby-traps, and other devices against civilians (see also Amended Protocol II, art. 3(7), which further encompasses non-international armed conflict).

Customary Status

It must be recalled that the foundational premise of reprisals is that they afford parties to a conflict a means of self-help enforcement in the face of IHL violations. However, as the ICTY noted in Kupreškić,

It should be added that while reprisals could have had a modicum of justification in the past, when they constituted practically the only effective means of compelling the enemy to abandon unlawful acts of warfare and to comply in future with international law, at present they can no longer be justified in this manner. A means of inducing compliance with international law is at present more widely available and, more importantly, is beginning to prove fairly efficacious: the prosecution and punishment of war crimes and crimes against humanity by national or international courts (¶ 530).

This reality, inter alia, has led to increasing acceptance of customary law limitations and prohibitions on reprisals.

As noted, the 1949 Geneva Conventions prohibitions are well-recognized as reflecting customary international law. Thus, for instance, those who are hors de combat because they are wounded or prisoners of war may not be the object of reprisal action. The question today is whether the additional reprisal rules found in Additional Protocol I and elsewhere have attained customary law status (a topic that merits far greater analysis than is possible here). Some States are skeptical. For example, the DoD’s Law of War Manual notes that the United States “has expressed the view that AP I’s provisions on reprisal are counterproductive and that they remove a significant deterrent that protects civilians and war victims on all sides of a conflict” (§, citing State Department Legal Adviser Abraham Soafer’s 1987 comments on AP I).

On the one hand, it must be acknowledged that there has been very little practice of reprisal since 1949. A notable exception was the Iran-Iraq War of the 1980s, during which both sides attacked cities claiming a right to reprisal (see, e.g., UN Doc. S/15743, (4 May 1983); Doc. S/18704 (18 Feb. 1987); Doc. S/18648 (2 Feb. 1987); Doc. S/18721 (25 Feb. 1987); Doc. S/18728 (27 Feb. 1987); Doc. S/18945 (24 June 1987)). A few other examples are set forth in the late Frits Kalshoven’s classic work, Belligerent Reprisals (ch. VI). Overall, though, reprisals are rare.

But on the other hand, there appears to be continuing acceptance that reprisals are not forbidden altogether. In 2007, for instance, the ICTY Trial Chamber affirmed the position taken in Kupreškić that certain reprisals (albeit not against civilians) continued to be permissible subject to very stringent conditions (Martić ¶¶ 465-67, confirmed in 2008 by Appeals Chamber, ¶¶ 263-67). As noted, the United States agrees (DoD Law of War Manual, § 18.18). To illustrate a reprisal that would not be prohibited, both the U.S. Navy/Marine Corps/Coast Guard Commander’s Handbook on the Law of Naval Operations and the Commander’s Handbook on the Law of Land Warfare cite the “use of weapons forbidden by the 1907 Hague Regulations to counter the use of the same weapons by an enemy on combatants who have not yet fallen into the hands of the enemy.” (¶ 8-80 and § 6.2.4, respectively).

But which particular prohibitions beyond those in the Geneva Conventions have achieved customary law status? The most important of the reprisal rules in Additional Protocol I is that forbidding reprisals against civilians. In its Customary International Humanitarian Law study, the ICRC observed (commentary to Rule 146),

[I]t is difficult to conclude that there has yet crystallized a customary rule specifically prohibiting reprisals against civilians during the conduct of hostilities. Nevertheless, it is also difficult to assert that a right to resort to such reprisals continues to exist on the strength of the practice of only a limited number of states, some of which is also ambiguous. Hence, there appears, at a minimum, to exist a trend in favour of prohibiting such reprisals.

Accordingly, the ICRC only asserted that reprisals against persons protected by the Geneva Conventions are prohibited under customary law.

Yet, in Kupreškić, the ICTY Trial Chamber held that the customary prohibition of reprisals against civilians in the hands of the adversary that is reflected in Geneva Convention IV has broadened to include all civilians (see also Martić, ICTY 1996, Rule 61 Decision, ¶¶ 15-17). The Tribunal opined, “[i]t is difficult to deny that a slow but profound transformation of humanitarian law under the pervasive influence of human rights has occurred. As a result, belligerent reprisals against civilians and fundamental rights of human beings are absolutely inconsistent legal concepts” (¶ 529). It further noted that “principles of international humanitarian law may emerge through a customary process under the pressure of the demands of humanity or the dictates of public conscience, even where State practice is scant or inconsistent” (¶ 528). Thus, while the Additional Protocol I, Article 51(6), prohibition may not have been customary in 1977, two decades later, it purportedly had achieved that status. In 2011, the International Criminal Court found that the prohibition equally applies in non-international armed conflict (Mbarushimana, Decision on Confirmation of Charges, ¶ 143).

The ICTY’s assertion of customary law status drew a sharp rebuke from the United Kingdom in its Manual of the Law of Armed Conflict, which asserts, “the court’s reasoning is unconvincing and the assertion that there is a prohibition in customary law flies in the face of most of the state practice that exists. The UK does not accept the position as stated in this judgment” (§ 16.20). And the U.S. Commander’s Handbook on the Law of Naval Operations takes the position that  “[u]nder customary international law, members of the enemy civilian population, other than protected persons covered under the Fourth Geneva Convention, may be legitimate objects of reprisal” (§ 6.2.4).

Yoram Dinstein has split the baby, and appropriately so. He suggests that the fact that a State has violated IHL does not mean that the rights of individuals are lost because their State of nationality is breaching an IHL obligation (¶ 1044). By his approach, civilians (and others enjoying individual rights like POWs) remain safeguarded against reprisals even beyond the protections resident in treaty law. But Professor Dinstein distinguishes such reprisals from those directed at civilian objects: “The exclusion of civilian persons from the lawful scope of belligerent reprisals, spurred by basic precepts of human rights law, does not imply that every inanimate civilian object must be equally protected” (¶ 1059).

I agree on the basis that the logic outlined in Kupreškić is far less compelling in the case of objects. It also merits noting that in the Martić case, the shelling of Zagreb was considered unlawful as a reprisal because it was disproportionate, not because it targeted civilian objects (Judgment, ¶¶ 467-468). And the ICRC’s Customary IHL study’s Rule 147 only asserts that the prohibitions on reprisals against objects cited in the 1949 Geneva Conventions and 1954 Hague Cultural Property Convention enjoy customary law status.

Professor Dinstein also suggests that all of mankind has an interest in protecting the environment. This being so, “the fact that State A has caused unlawful damage to the natural environment cannot possibly justify compounding the injury by State B” (¶ 1045). Again, I find merit in the argument, for to argue otherwise would be to permit reprisal-related harm to States that are not violating IHL, including neutrals.

The status of reprisals against cultural property for States that are neither Party to Additional Protocol I nor the Cultural Property Convention is less well established. Professor Dinstein accurately notes that the prevailing view is that they are prohibited under customary law (¶ 1047). One prominent source taking that position is UNESCO’s Military Manual on Protection of Cultural Property, which labels such reprisals “absolutely prohibited” (p. 47).  While the Tallinn Manual experts, including me, could not achieve consensus on the matter, I believe that States are likely to view any future reprisal attack on cultural property as both a treaty and customary law violation. So does the ICRC (see commentary accompanying ICRC Customary IHL Study, Rule 147).

Reprisals during Non-international Armed Conflicts?

Treaty law does not directly address reprisals during non-international armed conflict, such as that which occurred in eastern Ukraine prior to Russia assuming “overall control” of the insurgent forces in the area. However, the ICRC asserts that the parties to such a conflict “do not have the right to resort to belligerent reprisals” (ICRC, Customary IHL Study, Rule 148). As support, it points to Common Article 3 of the 1949 Geneva Conventions, which prohibits violence to life and person, taking hostages, outrages on personal dignity, and the denial of a fair trial. It also requires humane treatment of those not directly participating in the hostilities. The provision undoubtedly reflects customary law.

More broadly, the ICRC argues,

There is insufficient evidence that the very concept of lawful reprisal in non-international armed conflict has ever materialized in international law. All practice describing the purpose of reprisals and conditions for resort to them refers to inter-State relations and originates from practice in the 19th and early 20th centuries. Recent practice relating to non-international armed conflicts has in no way supported the idea of enforcing the law in such conflicts through reprisals or similar countermeasures, but, on the contrary, has stressed the importance of the protection of civilians and persons hors de combat, of respect for human rights law and of diplomatic means to stop violations (Rule 148 commentary).

I find this argument compelling. It must be remembered that reprisal operates as a circumstance precluding the wrongfulness of an otherwise unlawful act or omission under IHL. Thus, this is not a case of needing to find State practice and opinio juris to establish crystallization of a prohibition. After all, that which is not prohibited is generally lawful in international law. Instead, they relate to the existence of an exception to extant IHL prohibitions. In the absence of State practice and opinio juris, therefore, conventional legal reasoning would support the ICRC position (see also Sassoli, International Humanitarian Law at 83-84).

Concluding Thoughts

It goes without saying that there is no justification for Russia’s cacophony of IHL violations in the law of reprisal. As a Party to Additional Protocol I, it is bound by robust limitations therein. But even if it were not, its operations do not satisfy the strict conditions applicable to whatever reprisals remain permissible in customary law. Any attempt by Russia to legally style its purported retaliatory operations as reprisals is untenable.

But the Russian claims of retaliation should cause States to pause when considering their position on reprisals. Those States that maintain reprisals are permissible in certain circumstances seek to preserve their supposed deterrent utility. In doing so, however, they leave the door open to claims by malevolent States like Russia, unfounded though they might be, that their IHL violations are justified as reprisals.

And there is always a risk that reprisal actions will lead to an escalatory spiral. Indeed, the State against which a reprisal is taken might believe in good faith that its original conduct was lawful and, in turn, conclude that it is entitled to engage in reprisals based on the enemy’s unlawful response. This risk was tragically illustrated during the air war of Second World War, which included target area bombing of civilian population centers (see discussion in Kalshoven, ch. V). Thus, the DoD Law of War Manual requires reprisals to be “resorted to only after a careful inquiry into the facts to determine that the enemy has, in fact, violated the law” (§; see also FM 6-27, ¶ 8-82).

Finally, the DoD Law of War Manual wisely cautions that even lawful reprisals might lead to adverse political and operational consequences (§ 18.18.4.). It warns that they can,

– “Divert valuable and scarce military resources from the military struggle and may not be as effective militarily as steady adherence to the law;”

– “Usually have an adverse impact on the attitudes of governments not participating in the conflict;”

– “Only strengthen enemy morale and will to resist;”

– “Frequently lead only to further unwanted escalation of the conflict by an adversary or a vicious cycle of counter-reprisals;” and

– “Render resources of an adversary less able to contribute to the rehabilitation of an area after the cessation of hostilities.”

States considering their position on any remaining right to reprisal in IHL would be well-advised to consider these realities carefully.


Michael N. Schmitt is the G. Norman Lieber Distinguished Scholar at the United States Military Academy at West Point. He is also Professor of Public International Law at the University of Reading and Professor Emeritus and Charles H. Stockton Distinguished Scholar-in-Residence at the United States Naval War College.


Photo credit: Pieter Bruegel the Elder via Wikimedia Commons


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Neutrality in the War against Ukraine

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The Russia-Ukraine War and the European Convention on Human Rights

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Deefake Technology in the Age of Information Warfare

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Ukraine and the Defender’s Obligations

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Are Molotov Cocktails Lawful Weapons?

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Russian Troops Out of Uniform and Prisoner of War Status

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On War

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The Other Side of Civilian Protection: The 1949 Fourth Geneva Convention

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Ukraine’s Legal Counterattack

by Michael Kelly

March 17, 2022

The ICJ’s Provisional Measures Order: Unprecedented

by Ori Pomson

March 17, 2022

Displacement from Conflict: Old Realities, New Protections?

by Ruvi Ziegler

March 17, 2022

A No-Fly Zone Over Ukraine and International Law

by Michael N. Schmitt

March 18, 2022

Time for a New War Crimes Commission?

by Diane Marie Amann

March 18, 2022

Portending Genocide in Ukraine?

by Adam Oler

March 21, 2022

Are Mercenaries in Ukraine?

by Robert Lawless

March 21, 2022

Abducting Dissent: Kidnapping Public Officials in Occupied Ukraine

by Katharine Fortin

March 22, 2022

Are Thermobaric Weapons Unlawful?

by Matt Montazzoli

March 23, 2022

A Ukraine No-Fly Zone: Further Thoughts on the Law and Policy

by Terry D. Gill

March 23, 2022

The War at Sea: Is There a Naval Blockade in the Sea of Azov?

by Martin Fink

March 24, 2022

Deportation of Ukrainian Civilians to Russia: The Legal Framework

by Michael N. Schmitt

March 24, 2022

Weaponizing Food

by Michael N. Schmitt

March 28, 2022

Command Responsibility and the Ukraine Conflict

by Noëlle Quénivet

March 30, 2022

The Siren Song of Universal Jurisdiction: A Cautionary Note

bySteve Szymanski and Peter C. Combe

April 1, 2022

A War Crimes Primer on the Ukraine-Russia Conflict

by Sean Watts and Hitoshi Nasu

April 4, 2022

Russian Booby-traps and the Ukraine Conflict

by Michael N. Schmitt

April 5, 2022

The Ukraine Conflict, Smart Phones, and the LOAC of Takings

by Gary Corn

April 7, 2022

War Crimes against Children

by Véronique Aubert

April 8, 2022

Weaponizing Civilians: Human Shields in Ukraine

by Michael N. Schmitt

April 11, 2022

Unprecedented Environmental Risks

by Karen Hulme

April 12, 2022

Maritime Exclusion Zones in Armed Conflicts

by Raul (Pete) Pedrozo

April 12, 2022

Ukraine’s Levée en Masse and the Obligation to Ensure Respect for LOAC

by Jann K. Kleffner

April 14, 2022

Cultural Property Protection in the Ukraine Conflict

by Dick Jackson

April 14, 2022

Results of a First Enquiry into Violations of International Humanitarian Law in Ukraine

by Marco Sassòli

April 14, 2022

Comprehensive Justice and Accountability in Ukraine

by Chris Jenks

April 15, 2022

Maritime Neutrality in the Russia-Ukraine Conflict

by David Letts

April 18, 2022

Cyber Neutrality, Cyber Recruitment, and Cyber Assistance to Ukraine

by Nicholas Tsagourias

April 19, 2022

Defiance of Russia’s Demand to Surrender and Combatant Status

by Chris Koschnitzky and Steve Szymanski

April 22, 2022

The Montreux Convention and Turkey’s Impact on Black Sea Operations

by Adam Aliano and Russell Spivak

April 25, 2022

Lawful Use of Nuclear Weapons

by Jay Jackson and Kenneth “Daniel” Jones

April 26, 2022

Litigating Russia’s Invasion of Ukraine

by Lawrence Hill-Cawthorne

April 27, 2022

Military Networks and Cyber Operations in the War in Ukraine

by Heather Harrison Dinniss

April 29, 2022

Building Momentum: Next Steps towards Justice for Ukraine

by Philippa Webb

May 2, 2022

Counternormativity and the International Order

by Dan E. Stigall

May 3, 2022

Destructive Counter-Mobility Operations and the Law of War

by Sean Watts and Winston Williams

May 5, 2022

Are We at War?

by Michael N. Schmitt

May 9, 2022

The Ukraine Conflict and the Future of Digital Cultural Property

by Ronald Alcala

May 13, 2022

Neutral State Access to Ukraine’s Food Exports

by James Kraska

May 18, 2022

Negotiating an End to the Fighting

by Michael N. Schmitt

May 24, 2022

Is the Law of Neutrality Dead?

by Raul (Pete) Pedrozo

May 31, 2022

Effects-based Enforcement of Targeting Law

by Geoff Corn and Sean Watts

June 2, 2022

U.S. Offensive Cyber Operations in Support of Ukraine

by Michael N. Schmitt

June 6, 2022

War Sanctions Steadily Degrade the Russian Maritime Sector

by James Kraska

June 7, 2022

The Atrocity Crimes Advisory Group & Ukrainian Prosecutions of Russian POWs – Part 1

by Chris Jenks

June 22, 2022

The Atrocity Crimes Advisory Group & Ukrainian Prosecutions of Russian POWs – Part 2

by Chris Jenks

June 24, 2022

The Atrocity Crimes Advisory Group & Ukrainian Prosecutions of Russian POWs – Part 3

by Chris Jenks

June 28, 2022

Putting “Overall Control” to the Test of the Third Geneva Convention

by Alessandra Spadaro

July 6, 2022

The Risk of Commercial Actors in Outer Space Drawing States into Armed Conflict

by Tara Brown

July 8, 2022

The Release of Prisoners of War

by Jeroen van den Boogaard

July 8, 2022

The Attack on the Vasily Bekh and Targeting Logistics Ships

by James Kraska

July 11, 2022

Lessons from Syria’s Ceasefires

by Marika Sosnowski

July 12, 2022

Documentation and Investigation Responses to Serious International Crimes

by Brianne McGonigle Leyh

July 13, 2022

Rebel Prosecutions of Foreign Fighters in Ukraine

by René Provost

July 15, 2022

Forced Civilian Labor in Occupied Territory

by Michael N. Schmitt

August 2, 2022

Forced Conscription in the Self-Declared Republics

by Marten Zwanenburg

August 8, 2022

Amnesty International’s Allegations of Ukrainian IHL Violations

by Michael N. Schmitt

August 8, 2022

Oil Tankers as “Environmental Time Bombs,” or Not

by Mark Jessup

August 12, 2022

The Escalating Military Use of the Zaporizhzhia Nuclear Plant

by Tom Dannenbaum

August 22, 2022

Protected Zones in International Humanitarian Law

by Michael N. Schmitt

August 24, 2022

Photos of the Dead

by William Casey Biggerstaff

August 19, 2022

Deception and the Law of Armed Conflict

by William Casey Biggerstaff

September 8, 2022

Data-Rich Battlefields and the Future of LOAC

by Shane ReevesRobert Lawless

September 12, 2022

Russian Crimes Against Children

by Oleksii KaminetskyiInna Zavorotko

September 14, 2022

Targeting Leadership

by Mehmet Çoban

September 16, 2022

Illegality of Russia’s Annexations in Ukraine

by Lauri Mälksoo

October 3, 2022

Russia’s Forcible Transfer of Children

by Alison Bisset

October 5, 2022

The Kerch Strait Bridge Attack, Retaliation, and International Law

by Marko MilanovicMichael N. Schmitt

October 12, 2022

Russian Preliminary Objections at the ICJ: The Case Must Go On?

by Ori Pomson

October 13, 2022

The Complicity of Iran in Russia’s Aggression and War Crimes in Ukraine

by Marko Milanovic

October 19, 2022

Attacking Power Infrastructure under International Humanitarian Law

by Michael N. Schmitt

October 20, 2022

Dirty Bombs and International Humanitarian Law

by Michael N. Schmitt

October 26, 2022

Doxing Enemy Soldiers and the Law of War

by Eric Talbot JensenSean Watts

October 31, 2022

Are Civilians Reporting With Cell Phones Directly Participating in Hostilities?

by Michael N. SchmittWilliam Casey Biggerstaff

November 2, 2022

Using Cellphones to Gather and Transmit Military Information, A Postscript

by Michael N. Schmitt

November 4, 2022

State Responsibility for Non-State Actors’ Conduct

by Jennifer Maddocks

November 4, 2022

Reparations for War: What Options for Ukraine?

by Luke Moffett

November 15, 2022

Further Thoughts on Russia’s Campaign against Ukraine’s Power Infrastructure

by Michael N. Schmitt

November 25, 2022

Russia’s Allegations of U.S. Biological Warfare in Ukraine – Part I

by Robert Lawless

December 2, 2022

Russia’s Allegations of U.S. Biological Warfare in Ukraine – Part II

by Robert Lawless

December 9, 2022

The THeMIS Bounty Part I: Seizure of Enemy Property

by Christopher Malis and Hitoshi Nasu

December 12, 2022

Classification of the Conflict(s)

by Michael N. Schmitt

December 14, 2022

The THeMIS Bounty Part II: Stealing Enemy Technology

by Christopher Malis, Hitoshi Nasu

December 16, 2022

The “I Want to Live” Project and Technologically-Enabled Surrender

by David Wallace, Shane Reeves

January 13, 2023

UN Peacekeepers and the Zaporizhzhia Nuclear Plant

by Alexander Gilder

January 20, 2023

What’s in a Name? Getting it Right for the Naval “Drone” Attack on Sevastopol

by Caroline Tuckett

January 23, 2023

Ukraine’s “Suicide Drone Boats” and International Law

by Charles M. Layne

January 25, 2023

The Impact of Sanctions on Humanitarian Aid

by Alexandra Francis

January 27, 2023

A Wagner Group Fighter in Norway

by Camilla Cooper

February 1, 2023

The Legal and Practical Challenges of Surrendering to Drones

by William Casey Biggerstaff,Caitlin Chiaramonte

February 8, 2023

Field-Modified Weapons under the Law of War

by Ronald Alcala

February 13, 2023

The Wagner Group: Status and Accountability

by Winston Williams, Jennifer Maddocks

February 23, 2023

The Law of Crowdsourced War: Democratized Supply Chains – Part I

by Gary Corn

March 1, 2023