Is the Lieber Code Humanitarian?

by | Jan 7, 2021

LIeber Code


Some critics maintain that the Lieber Code is not humanitarian. They are surprised and disappointed that Francis Lieber—one of the fathers of the modern law of war and an inspiration for the Hague Conferences—fails to meet their expectations. But such indignation is misplaced. Moreover, it raises the issue of how we use the term “humanitarian.”

True enough, the Lieber Code valorizes military necessity, authorizes destruction of civilian infrastructure useful to the enemy’s war effort, and advocates intense fighting. And, Lieber was not a humanitarian in the sense of Jean-Henri Dunant—who in his 1862 A Memory of Solferino drew attention to the suffering of the wounded on the battlefield and inspired the formation of the International Committee of the Red Cross. Lieber admired Dunant’s work, but his project was different.

Lieber wrote to provide practical guidance to officers and men on the ground at a time when a number of conflicting ideas regarding the law of war contended in America. During the Civil War very real questions faced the army, such as the status of irregular fighters and what to do with escaped enslaved persons reaching Union lines.

When seen in this context, the Lieber Code has much to offer humanity. The Code sought to civilize armed conflict at a time when rules and restraint were very much needed.

Guidelines for the Troops

The chief source on the law of war, and the basis of teaching at West Point at the time, was Emer de Vattel’s The Law of Nations of 1758. Vattel, a product of the Enlightenment, held that the modern, rational man should wage war in a controlled and moderate manner, without personal passion, and the civilian population was to be spared entirely.

For Lieber, himself a combat veteran, Vattel’s approach was not realistic. But neither was the approach taken by the widely distributed Cromwell’s Soldier’s Bible—a reproduction of the 1643 pamphlet carried by Oliver Cromwell’s Puritan army in the English Civil War. Cromwell’s Bible presented an altogether different sort of Christian warrior-ethic. The enemy soldier, for example, was considered an enemy of God.

Moreover, it was unlikely that the non-professional Union soldier would have exposure to Vattel. In fact, they likely did not have any useful guide to behavior on the battlefield, aside from the orders of their commanding officers. Sir Walter Scott was widely read at the time, and probably inspired a romantic ideal of chivalric generosity and faithfulness in the warrior. However, Scott’s vision was not much use tactically. Men were sermonized in church to be good Christian soldiers, but what, exactly, did that mean in the field?[1]

It was in this context that President Lincoln issued the Lieber Code as a concise field manual, General Order No. 100 of 1863.

Humanizing the Law of War

A number of features of the Lieber Code sought to civilize armed conflict.

Constraint. The notion that war is not mere savagery but is subject to law, and that soldiers are expected to act with restraint and follow rules, is the foundation of the Lieber Code. Article 15 provides, “Men who take up arms against one another in public war do not cease on this account to be moral beings, responsible to one another, and to God.”

In elaboration of this principle, the Lieber Code summarizes humanitarian aspects found in customary law. Two such rules are the requirement to avoid cruelty and infliction of unnecessary suffering, and the injunction that a wounded soldier who is incapable of fighting should not be further injured, but given medical aid.

Combatant’s Privilege. Another principal feature of the Code is the recognition that enemy soldiers are nevertheless human beings just like us—fighting for a cause that they believe in and/or following the orders of their government. The combatant’s privilege of the Lieber Code (Article 57) deems an enemy soldier to be a lawful combatant, not a murderer. If captured, he is to be given the status and protection of a prisoner of war. While this was not a novel idea, it needed to be stated—especially in the context of civil wars.

Application of the Law of War to Civil War. The Code provides a solution to what seemed a great political conundrum at the outbreak of the Civil War. While the Union desired to grant rebel soldiers the traditional protections of the law of war, the Confederacy did not have the status of a sovereign State. The rules of war were understood at the time to function only between States. The United States could not be seen to recognize the Confederacy as a State, as that would effectively accept the South’s position that it had the lawful right to secede.

Article 152 provides, “When humanity induces the adoption of the rules of regular war towards rebels … it does in no way imply a partial or complete acknowledgment of their government, if they have set one up, or of them, as independent or sovereign power.” Thus, in an exercise in legal subtlety, Lieber said we could look at the war one way for humanitarian purposes and another way for diplomatic purposes, enabling the extension of combatant privileges to the rebels without injury to U.S. international relations.

Similarly, Lieber reserved the right to try lawful combatants for unlawful treason. Article 154 provides that the Code’s grant of the combatant’s privilege to rebels in the field does not preclude prosecuting them for treason afterwards. That is, treating them as lawful combatants does not make their rebellion itself lawful.

Military Necessity. The central element of Lieber’s unique brand of humanitarianism is the doctrine of military necessity. This may seem a surprising claim, as it is the broad license given in the Code to military necessity that draws the greatest criticism from its detractors. Yet military necessity, when properly understood, serves to limit the lawful actions of the army to those necessary or expedient to achieve stated purposes. This idea of the instrumentality of war thus contains a duality, in that it both authorizes stern measures (say, depriving a population of the means to support the army, as in Article 15) and limits measures to those tethered to the military mission. This would for example rule out gratuitous infliction of suffering and other depredations (Article 68).

Established Practices. Actions in furtherance of military necessity are also limited by Article 14’s qualification “and which are lawful according to the modern law and usages of war.” This proviso admits into the Lieber Code generally agreed restrictions—like a prohibition on poison—even if the logic of military necessity alone would not preclude or limit such practices.

Cultural Objects. Among the humanitarian elements of the Code is its treatment of cultural objects. Article 34 provides a special exemption for the property of churches, hospitals, universities, and museums from the license found in Article 31 for the conquering army to freely appropriate public property. Lieber went even further in Article 35, imposing a positive duty to take care of (not merely spare from destruction) classical works of art and valuable instruments like telescopes. These are to be protected from “all avoidable injury” even when located in a fortified place under bombardment.

This was not mere sentimentality. Lieber had explained in his Manual of Political Ethics that this was a measure to assure peace. He considered that if the victor would carry off works of art “it galls the conquered nation beyond the time of war, and, as peace requires mutual good will … the carrying off of these works would awaken feelings opposed to continued peace.” Likely, Lieber was remembering the bitterness that followed the Napoleonic acts of plunder in the French wars of his youth.

The “Naked” Soldier. Article 69 presents one of the most curious—and humanitarian— provisions to be found in the Code. It states, “Outposts, sentinels, or pickets are not to be fired upon, except to drive them in, or when a positive order, special or general, has been issued to that effect.” This is an exception to the general liberty to kill enemy soldiers—which sentinels plainly are. Lieber seems to be recognizing the noted reluctance of soldiers to shoot a quiet, solitary enemy soldier.

War Crime Prosecutions. Lieber did not use the term “war crime,” but his work laid the foundation for personal responsibility without the excuse that a soldier was “just following orders.” Article 71 of the Code contains the remarkable statement that not only an enemy soldier but also a friendly soldier is subject to the death penalty if he intentionally harms or kills a disabled enemy, or orders it done.

Lieber had earlier explained the principle of common law that “every officer remain[s] individually answerable for his acts … [N]o positive order by the supreme executive, even though this be a king, as in England, be allowed as a plea for impunity.” Together, as Gary Solis has pointed out, principles form the basis for the modern jurisprudence under which a soldier may be held personally liable for criminal behavior, and cannot assert as a defense that he was merely following (unlawful) orders. Lieber has been credited with being the first to point out this unique principle in Anglo-American jurisprudence. The opposite ethos was being developed at the same time in Prussia, where the “professionalism” of the modern soldier would lead him to be untroubled by matters of conscience.

Protecting the Soldier. Lieber understood that soldiers would not like to think themselves murderers. They would like to serve with professional honor and return home with a clear conscience. One enormous virtue of the Lieber Code was the guidance it provided to the conscientious soldier. Clarity about right and wrong in the midst of the confusion and horror of war is a great gift contained in the Lieber Code—and, a humanitarian benefit not only to civilians and prisoners, but also to the people who are called upon to deploy the violence.

Emancipation. Equality. Another humanitarian aspect of the Code is its radical grant of freedom to enslaved persons and its demand for equal treatment of African American soldiers. Article 43 declares that any enslaved person reaching Union lines becomes ipso facto free and can never be returned to slavery. (This actually went further than the Emancipation Proclamation, which limited liberation to persons in states in rebellion.) This was a novel addition to the law of war, and indeed contrary to the position taken by the United States when the British liberated American slaves. Articles 57 and 58 require that the South grant captured African American soldiers full prisoner-of-war status, regardless of their color or previous condition of servitude. The death penalty is specified for selling a captured soldier into slavery.  

Postscript: A Modest Proposal on the Term “Humanitarian”

We will have fewer arguments if we are more careful about using the term “humanitarian.” It has too many conflicting meanings. Primarily, it concerns the alleviation of human suffering. Yet, the law of armed conflict, also known as international humanitarian law, implicitly recognizes that the infliction of suffering during combat is lawful.

Some humanitarian work seeks to address the causes of suffering, such as pacifism (which seeks to alleviate suffering by preventing war in the first place). Its advocates might object to laws like the Lieber Code which, as Michael Walzer has said, serve “as a program for the toleration of war when what is needed is a program for its abolition.”

Another conflict is that humanitarianism is often at odds with seeking justice. The pursuit of justice may, and often does, require the use of force—with all of its attendant human misery (at least in the short term). The simple humanitarian impulse to stop the violence is unburdened with the problem of any predicate injustice.

My modest proposal is that we should think of the Lieber Code and LOAC generally as humanizing warfare. That means being sympathetic to people; adapting the subject to the various qualities and weaknesses of human nature; and, making it more understandable to human beings.


Richard Salomon is a Department of Law Visiting Lecturer at the United States Military Academy, West Point, New York, and is the author of The Unsuspected Francis Lieber (2018). Previously, Rick was in private law practice in New York City.


[1] Regarding the Fourth Commandment, “Thou shalt not kill,” Lieber had explained in 1838 that it should be considered in context as “Thou shalt not unjustly kill.”