Chapter III Belligerent Reprisals

The discussion of various rules of international humanitarian law in the previous chapters, particularly those norms existing prior to 1949, was almost invariably accompanied by reference to the perennial caveat of belligerent reprisals. Belligerent reprisals are deliberate violations of the laws of war, made by a party to a conflict in response to the prior violation of those same laws by the opposing party, and for the purpose of coercing the latter to cease its unlaw- ful action. More often than not, reprisals have been directed at persons other than those responsible for the initial wrongdoing and, as such, are based on a concept of collective responsibility whereby innocent persons are liable to suf- fer for the acts of others. Consonant with the progression of the law on col- lective punishment and hostage-taking, belligerent reprisals have been evolving from an accepted means of law enforcement to a prohibited practice, although, contrastingly, they have not been completely outlawed, and several States have expressly sought to retain the power to take certain reprisals. The question of belligerent reprisals, therefore, remains a contemporary one. The doctrine of belligerent reprisals has concerned scholars of the laws of war throughout history and has been the subject of much concerted study.1 For this reason, and owing to the unresolved nature of the reprisals question, the format of this chapter will depart somewhat from that of the preceding chap- ters. It will trace more briefly the evolution of the law of belligerent reprisals, following which consideration will be given to the customary status and scope of the more recent conventional laws on reprisals. Recourse will be made to the views of States who favor retention of the doctrine in certain instances and to the relevant jurisprudence of the International Criminal Tribunal for the Former Yugoslavia (ICTY). The applicability of this traditionally interstate doc- trine in the context of noninternational armed conflicts will also be considered. In challenging the legality of belligerent reprisals, measures that invariably tend to rely upon an outmoded notion of collective responsibility, the relationship between the laws of armed conflict and international law will also be analyzed. a. The Customary Law of Belligerent Reprisals Belligerent reprisals have acted as a sanction of the international laws of war, closely related to reprisals in peacetime2 and distinct from acts of

1 For the most comprehensive study of the subject, see Frits Kalshoven, Belligerent Reprisals, Leyden: A.W. Sijthoff, 1971. 2 These reprisals are measures of force, falling short of war, which are taken by one

131 132 • Collective Responsibility Under retorsion.3 Consequently, reprisal measures can only be taken in response to a prior violation of the laws of war and for the purpose of enforcing compliance with those laws. A number of other requirements, such as observance of the principles of proportionality and subsidiarity, have been established by custom and found expression in two early documents on the laws of war: the Lieber Code of 18634 and the 1880 Oxford Manual on the Laws of War on Land.5 The pertinent provisions of the Lieber Code read: The can no more wholly dispense with retaliation than can the law of nations, of which it is a branch. Yet civilized nations acknowl- edge 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. Retaliation will, therefore, never be resorted to as a measure of mere revenge, but only as a means of protective retribution, and more- over, 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 far- ther and farther from the mitigating rules of regular war, and by rapid steps leads them nearer to the internecine war of savages.6

State against another in response to a prior violation of international law by the latter. In addition to their law enforcement function, such reprisals are seen as being a forcible means of settling disputes between States and for securing redress from another State for its misdeeds. The legality of peacetime reprisals is governed by the jus ad bellum. See generally Yoram Dinstein, War, Aggression and Self-Defence, 2nd edn., Cambridge: Cambridge University Press, 1994, pp. 215–226; Derek Bowett, “Reprisals involving Recourse to Armed Force,” 66 American Journal of International Law 1 (1972) 1; H.W. Halleck, International Law; or Rules Regulating the Intercourse of States in Peace and War, San Francisco: H.H. Bancroft and Co., 1861, pp. 297–303. For an overview of the ancient practice, see Coleman Phillipson, The International Law and Custom of Ancient Greece and Rome, Volume II, London: Macmillan and Co., Ltd., 1911, pp. 353–364. 3 These are measures of a lawful nature taken in response to the prior unfriendly, yet lawful, acts of another State. Their aim is to induce the other State to cease its harmful conduct. Examples include the severance of diplomatic relations or the withdrawal of fiscal or trade concessions. See J.G. Starke, Introduction to International Law, 8th edn., London: Butterworths, 1977, p. 549. 4 Instructions for the Government of Armies of the United States in the Field, pre- pared by Francis Lieber, promulgated as General Orders No. 100 by President Lincoln, 24 April 1863, reprinted in Dietrich Schindler and Jirí Toman (eds.), The Laws of Armed Conflict: A Collection of Conventions, Resolutions and Other Documents, Dordrecht: Martinus Nijhoff, 1988, p. 3. 5 Oxford Manual on the Laws of War on Land, adopted by the British Institute of International Law, 1880 reprinted in Dietrich Schindler and Jirí Toman (eds.), The Laws of Armed Conflict: A Collection, p. 35. 6 Articles 27–28. Although Francis Lieber did not use the term reprisal, the language of the Articles strongly suggests that he sought to address the doctrine: retaliation had