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Max Planck Encyclopedia of Public International Law [MPEPIL]

Lieber Code

Patryk I Labuda

1815 to World War I — Conduct of hostilities — Ius in bello

Published under the auspices of the Max Planck Foundation for International Peace and the Rule of Law under the direction of Rüdiger Wolfrum.

A.  Introduction

The Lieber Code is sometimes referred to as the first modern codification of the laws of war (Humanitarian Law, International). Promulgated at the height of the American Civil War (1861–65), it proposed a set of rules to govern the conduct of hostilities by the United States armies (‘Union’ or ‘North’) against the Confederate States of America (‘Confederacy’ or ‘South’). Named after its main author, Francis Lieber, the Code regulated a variety of legal issues, in particular the interplay between military necessity and the principle of humanity (Humanity, Principle of), the status of persons involved in armed conflict (Combatants; Civilian Population in Armed Conflict), as well as permissible methods and means of warfare (Warfare, Methods and Means). A concise restatement of then existing custom, Lieber’s work lies at the heart of many subsequent efforts to devise binding rules of international humanitarian law, including several countries’ manuals on the laws of armed conflict and at the Hague Peace Conferences (1899 and 1907).

B.  Historical Background

The civil war between the South and the North raised a variety of legal issues relating to non-international armed conflict (Armed Conflict, Non-International). Shortly after the outbreak of hostilities, the Union was confronted with the question of whether to treat captured Confederate soldiers as traitors, subject to the death penalty under domestic law, or rather as prisoners of war (‘POW’), under the international law of war. Given that it did not want to recognize the legality of the Confederacy’s secession, the North adopted pragmatic policies acknowledging the existence of hostilities, but without legitimizing the South’s claims to independence (Territorial Integrity and Political Independence; Self-Determination). For instance, two military orders issued in 1861 (General Orders 8 and 13) granted Confederate soldiers POW protections, thereby implicitly acknowledging the South’s belligerency. However, as the conflict festered, Union commanders, bereft of legal guidance, reached conflicting decisions on various legal questions. Subsequent military orders dealt with such questions on an ad hoc basis, but there was no generally applicable Union policy on the laws of war.

Cognizant of the problem, in late 1862, Henry W Halleck, general-in-chief of the Union armies, asked Francis Lieber, a Columbia Law School professor, to propose a set of detailed rules that could guide the Union’s war effort. Lieber, a native of Prussia who had fought in the Napoleonic Wars and later immigrated to the United States, was a respected scholar with strong pro-Union views. He had published on, inter alia, international law, and began teaching a course on ‘The Laws and Usages of War’ at Columbia in 1861. Hostile to slavery, despite living in South Carolina for 21 years, he had a deep personal investment in the Civil War, with two of his sons fighting for the Union and a third dying in combat for the South.

In early 1863, Lieber drafted a short manual restating the main principles and rules applicable in times of war. The text was endorsed by a committee of four generals and then promulgated, in May 1863, by the Union President, Abraham Lincoln, as ‘General Orders, No. 100: Instructions for the Government of Armies of the United States in the Field.’ Much to Lieber’s disappointment, the term ‘code’ was dropped from the document (a codification would have required legislative approval and Lincoln wanted to avoid a protracted debate in the US Congress). Issued as an executive order, the Instructions—referred to as the ‘Lieber Code’ since the end of the Civil War—were distributed to officers in the field, and served as the main authority on legal matters arising from the war until the end of hostilities in 1865. Though the South initially denounced the Code as ‘confused, unassorted, and undiscriminating’ (James Seddon to Robert Ould [24 June 1863] Official Records series 2 vol 6, 41), and continued to object to some of its provisions until the end of the war, the Confederate government did, in fact, endorse and apply many of its rules.

C.  The Code and Its Contents

The Lieber Code codified ‘that branch of the law of nature and nations which is called the law and usages of war on land’ regulating ‘action between hostile armies’ (Art. 40). A succinct compilation of then existing rules and custom, it addressed a wide range of topics. Several core principles of modern international humanitarian law are discernible in the text, albeit with significant differences as to their scope: the principles of humanity (Humanity, Principle of) and military necessity, the distinction between civilians and combatants, and certain inviolable rules such as the prohibitions of perfidy or torture (Torture, Prohibition of) (see below). Conversely, the Code also included norms that are no longer considered admissible in modern international humanitarian law, for instance giving no quarter to the enemy (Arts 61–63, 66), starvation of non-combatants (Art. 17), or executions of prisoners of war (Art. 59 in fine).

The Code consisted of just 157 provisions, subdivided into ten sections. Though the first section laid down a few general principles, the Code was not a systematic or comprehensive treatment of the law of war. Norms of general applicability frequently appeared alongside very detailed rules, and unlike the dry legalistic prose of modern codifications, many rules were explained in a vivid and verbose manner. Realizing that the Code would be distributed in the middle of an on-going war, Lieber wanted the text to be sufficiently self-explanatory to enable direct use. The brain child of one person, the Code’s style also reflected Lieber’s own involvement with the conflict and the battlefield realities of the American Civil War.

The Lieber Code is notable for not being confined to the law of war in the narrow sense (ius in bello; Lieber consistently used the term ‘law of war’, instead of its modern equivalents: international humanitarian law or the law of armed conflict). Writing in the just war tradition, Lieber incorporated ethical considerations into the text, which sometimes blurred the difference between ius in bello and ius ad bellum (Use of Force, Prohibition of). As a result, the Code regulated a number of familiar law-of-war topics, including the distinction between combatants and civilians, rules applicable to prisoners of war, proscribed methods of war, the treatment of irregular troops (Arts 81–104, 153–55), rules for the confiscation and destruction of property in enemy territory (Arts 31–33), and the protection of cultural property (Arts 34–36; Cultural Property, Protection in Armed Conflict). However, it also addressed broader issues, such as the nature of states and sovereignties, the nature of ‘public war’ (Art. 20), and the permissible ends of war (Arts 29–30).

D.  Specific Issues

1.  Military Necessity and Humanity

In a well-known passage, the Lieber Code defined military necessity as ‘… consist[ing] in the necessity of those measures which are indispensable for securing the ends of war, and which are lawful according to the modern law and usages of war’ (Art. 14). Depending on whether emphasis is placed on the first or second part of the sentence, the clause could be read as either a limitation of the methods of war or license for unbridled destruction. The Code’s norms reflected this tension between what Lieber perceived as the necessities and ends of war, on the one hand, and the principles of ‘justice, honor, and humanity’ (Art. 4), on the other.

The Code invoked the principle of humanity (Humanity, Principle of) in several provisions; most notably, it proclaimed that ‘military necessity does not admit of cruelty—that is, the infliction of suffering for the sake of suffering or for revenge … [and] does not include any act of hostility which makes return to peace unnecessarily difficult’ (Art. 16). Later it added: ‘Peace is [the] normal condition; war is the exception’ (Art. 29). The Code’s emphasis on the dictates of humanity was reflected in its provisions on the ethical and humane treatment of civilian populations (disclaiming a common pre-19th century norm that made all civilians enemies by association), the prohibition on the use of malice, poison and torture, (Arts 68, 22), and its detailed exposition of the rights and duties that prisoners of war and their captors possessed (Arts 49–80, 105–10).

10  Despite the humanitarian impulses of some provisions, the Code subordinated the principle of humanity to the overriding demands of military victory. ‘To save the country is paramount …’, the Code famously proclaimed (Art. 5), reflecting Lieber’s belief that nationalism was a supreme value in the conflict between the South and the North. Chief among Lieber’s sources of inspiration was Carl von Clausewitz, the renowned Prussian military theorist, whose imprimatur can be found in provisions such as: ‘The more vigorously wars are pursued the better it is for humanity. Sharp wars are brief’ (Art. 29). Nationalism, realism and Enlightenment principles formed the doctrinal fulcrum of the Code, which stood in stark contrast to the European tradition of humanitarianism epitomized by the codification efforts of the International Committee of the Red Cross (ICRC).

11  Thus, while the Code embraced humanity as a core tenet of the law of war, violations of humanitarian norms were justifiable in cases of military necessity, which Lieber appeared to assimilate with the righteousness of the cause of war. Because the Code conflated ius in bello and ius ad bellum principles, it implicitly justified both humane and cruel wars. In other words, though humanity remained a basic feature of the Code, every norm could be derogated from in times of military necessity. Distinct from their modern iterations, Lieber’s principles of humanity and military necessity are better understood as a validation of just war theory, in which the justness of the cause trumped, ultimately, all other considerations.

2.  The Principle of Distinction

12  The Lieber Code distinguished between ‘combatants’ and ‘non-combatants.’ Only the former were entitled to the privilege of belligerency, or—in modern parlance—the combatant’s privilege: ‘So soon as a man is armed by a sovereign and takes the soldier’s oath of fidelity he is a belligerent; his killing, wounding, or other warlike acts are no individual crimes or offenses’ (Art. 57). Soldiers were allowed to participate in combat, without being liable to criminal prosecution under national law, as long as they did not violate the laws of war (Arts 44 and 47). Upon capture, they were also entitled to prisoner-of-war treatment (see below).

13  Reflecting the realities of the Civil War, where various Confederate sympathizers operated behind enemy lines and engaged in the equivalent of modern ‘irregular and asymmetric’ warfare, the Code set out in great detail who enjoyed protected status as a combatant. Thus, partisans, or ‘soldiers armed and wearing the uniform of their army’ (Art. 81), and people participating in a levée en masse (Art. 51) enjoyed the privilege of belligerency. By contrast, guerrilla forces (Art. 82, the term did not appear in the Code itself, but is well known from Lieber’s other writings), scouts and single soldiers (Art. 83), armed prowlers (Art. 84), war rebels within occupied territory (Art. 85) and spies (Art. 88) did not qualify as combatants. Their actions were, in most cases, punishable by death.

14  The Code’s detailed regulation of combatancy contrasted with its terse rules on the status and rights of ‘non-combatants’ (Civilian Population in Armed Conflict). Influenced by the pre-modern tradition of the law of war, Lieber considered ‘[t]he citizen or native of a hostile country … an enemy, as one of the constituents of the hostile state or nation…’ (Art. 22). Although this norm appeared to validate the view that non-combatants were exposed to the hardships of war by virtue of their assimilation with the enemy (Enemies and Enemy Subjects), other provisions nuanced this position. For instance, the Code stated that ‘[i]n modern regular wars … protection of the inoffensive citizen of the hostile country is the rule …’ (Art. 25), adding elsewhere that ‘[p]rivate citizens are no longer murdered, enslaved, or carried off to distant parts …’ (Art. 23).

15  However, the Code also established a number of derogations from the principle that civilians should be spared from combat. Though it embraced the principle of distinction generally, and included a few protections for non-combatants, Union commanders were permitted to starve the unarmed belligerent if ‘it leads to the speedier subjection of the enemy’ (Art. 17), drive back non-combatants to a besieged area ‘so as to hasten on the surrender’ (Art. 18), and bombard cities without prior notification (Art. 19; Bombardment). The Confederacy denounced these aspects of the Code, anticipating presciently that it authorized Union commanders to engage in harsh combat. Arguably, General William T Sherman, in consultation with General Halleck, put into practice these very derogations during the evacuation of Atlanta’s civilian population and his ‘scorched earth’ campaign in Georgia in 1864 (known as Sherman’s ‘March to the Sea’).

3.  Prisoners of War

16  Besides defining who could benefit from prisoners of war (‘POW’) status (in principle, everyone entitled to combatant status), the Code contained detailed rules regarding their treatment. Thus, ‘[a] prisoner of war is subject to no punishment for being a public enemy, nor is any revenge wreaked upon him by the intentional infliction of any suffering, or disgrace, by cruel imprisonment, want of food, by mutilation, death, or any other barbarity’ (Art. 56). Further clauses addressed conditions of confinement (Arts 74, 75 and 76), methods of surrender (Art. 73) and how to perform prisoner swaps (Art. 105–10). Although both the Union and the Confederacy struggled to meet the Code’s requirements regarding POWs, Southern prison camps became especially infamous during the war due to their poor detention standards.

17  Despite its humanitarian protections for prisoners, the Code did not outlaw the possibility of retaliatory measures against POWs (Art. 59). In fact, the possibility of prisoner executions in retaliation for violations of the laws of war committed by the enemy was expressly permitted. The Union and the Confederate governments resorted to retaliation against POWs on a number of occasions. The Civil War’s horrors prompted efforts to ameliorate the protection of POWs, leading to the 1929 Geneva Convention relative to the treatment of Prisoners of War.

4.  Prohibited Methods of War

18  The Code appeared to lay down several peremptory prohibitions. It did not permit ‘the use of poison in any way’ (Art. 16), or resorting to torture (Arts 16 and 80; Torture, Prohibition of) or perfidy (Arts 16, 63, 65, 101 and 117). The use of enemy uniforms or enemy emblems was banned (Emblems, Internationally Protected). Abusing flags of protection (Flags of Truce) was considered an act of bad faith, which allowed a party to the conflict to stop recognizing their validity. It remains unclear whether Lieber’s doctrine of military necessity (see above) permitted derogations from these prohibitions, as no court cases tested their scope during the Civil War.

5.  Retaliation

19  Though Lieber acknowledged the ‘stern’ nature of belligerent reprisals, the Code proclaimed that ‘the law of war can no more wholly dispense with retaliation than can the law of nations….’ (Art. 27). It required only that retaliation (Lieber used this term, not the modern equivalent ‘reprisal’) be used as a last resort (‘unavoidably’) and ‘after careful inquiry into the real occurrence and the character of the misdeeds that may demand retribution’ (Art. 28). Though the Code did not actually define retaliation, both the Union and the Confederacy used a wide range of retaliatory measures to sanction prior violations of the laws of war, as an inducement to cease further violations, and as a bargaining chip in disputes over the legality of the opponent’s war methods. Confederate reprisals against black Union soldiers generated significant controversy during and after the war (see below).

6.  Slavery

20  The Union and the Confederacy disagreed profoundly over the status of slaves in the Civil War. Although the pre-Civil War US Constitution authorized and protected slavery, the legal status of slaves entering Union territory emerged as a highly contentious issue shortly after the outbreak of hostilities. Initially the Union had no unified policy on how to treat runaway slaves, which led to conflicting decisions by its generals. Some adhered to antebellum law and returned slaves to their Southern masters, others declared them contraband (confiscated property), while yet others set them free. In March 1862 Lincoln ordered runaway slaves to no longer be returned to their masters, and in January 1863, by way of the Emancipation Proclamation, all slaves in Confederate—but not Union—territory were declared free. This triggered the Union’s recruitment of large numbers of black soldiers, including many former slaves who had escaped from the South.

21  The Confederacy argued consistently throughout the war that the laws of war prohibited the freeing of enemy slaves, who—from a legal standpoint—remained their masters’ private property. Pre-Civil War American doctrine and practice supported this view, with the United States government denouncing the unlawful and uncompensated taking of slaves by the British during the Revolutionary War and the War of 1812 (Witt 70–79). Attempts to free and enlist slaves were an inducement to ‘servile insurrection’, which—according to the Confederate secretary of war, James Seddon—constituted ‘a departure from the usages of nations and an abandonment of the rules of civilized warfare’ (James Seddon to Jefferson Davis [3 November 1864 (Official Records series 4 vol 3, 769). The logical conclusion, argued the Confederacy, was that runaway slaves should be returned to their masters. As for runaway slaves already fighting on behalf of the Union, given that they lacked combatant status, the South argued they could be either lawfully re-enslaved or summarily executed as criminals.

22  Lieber waded into this fractious debate by arguing that the law of nations prohibited discrimination based on colour (Art. 58), and that, under the law of war, slaves who crossed into enemy territory became free (Arts 42 and 43). The Code required all soldiers—implicitly also black soldiers (whether former slaves or free blacks)—to be accorded combatant status, and thus POW protections upon capture. Thus, it also prohibited executions of black soldiers or their white commanders (Art. 57). Re-enslavement was explicitly prohibited (Art. 58). The South rejected these aspects of the Lieber Code and insisted that former slaves did not enjoy combatant status. This led to many disagreements. Rejecting the Confederacy’s policy of denying POW protections to black soldiers, the Union suspended prisoner exchanges on a few occasions. Confederate commanders refused to negotiate with blacks under a flag of truce. Most seriously, credible and well-documented reports emerged during the conflict of racial atrocities perpetrated by Confederate troops. Historians agree that executions of black troops occurred, though disagreement persists as to the scale and nature (in particular, whether the Confederacy actually endorsed a ‘no quarter’ policy for black Union troops) of the practice.

E.  Significance and Assessment

23  Historians agree that the Lieber Code’s impact during the Civil War was probably scant. Most commanders knew but ignored the Code. Though a few military commissions invoked the Code in trials involving the laws of war, its greatest influence came after the cessation of hostilities. Several militaries adopted Lieber’s rules (eg the Netherlands, Great Britain, Spain, Russia and France), initially with few amendments (eg the Prussian army translated and adopted the Code as such), and later with more substantial revisions that reflected the changing realities of war. According to one historian, Lieber’s codification was ‘the quarry from which all the subsequent codes were cut’ (Best 171).

24  The Code’s impact on the international community’s efforts to regulate warfare is equally noteworthy. It lies at the heart of several international projects to codify international humanitarian law at the turn of the 20th century, in particular the 1874 Brussels Conference (International Declaration concerning the Laws and Customs of War), the Institut de droit international’s 1880 Oxford ‘Manuel des lois de la guerre sur terre,’ the Hague Peace Conferences (1899 and 1907), and the Regulations respecting Laws and Customs of War on Land annexed to the fourth Hague Convention of 1907. Though traces of the Code are, arguably, still visible in the 1949 Geneva Conventions, the better view is that Geneva law departs considerably from Lieber’s conception of humanitarianism, marking a new chapter in the development of international humanitarian law (Giladi ‘A Different Sense of Humanity’ 81–116).

25  Although the Lieber Code was more ‘a persuasively written essay on the ethics of conducting war’ (Freidel 335) than a codification in the traditional sense of the term, Lieber’s greatest achievement was his ability to bring together various strands of international legal doctrine, just war theory and Enlightenment rationalism to produce a clear and comprehensible restatement of the law of war. Nothing like this had been tried before, and Lieber presciently anticipated many of the problems international humanitarian law grapples with to this day. Yet, despite all its strengths, the Code also contained weaknesses, some of which became apparent after Lieber’s death. For instance, the Code’s revised rules generated controversy during the Philippine–American War of 1899–1902, where US forces endorsed harsh military tactics, including torture of civilians, and ordered retaliation against Filipino prisoners (Witt 353–61). Reconciling the dictates of humanity and the realities of war, a struggle at the heart of Lieber’s codification, remained a challenge for his successors, and continues to be the greatest challenge facing modern international humanitarian law.

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