Wikipedia Deep Dive

War crime

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The First War Criminal

In 1474, a knight named Peter von Hagenbach stood before an unusual tribunal. The Holy Roman Empire had assembled judges to try him not for treason or rebellion, but for something that had no name yet: the crimes his soldiers had committed under his command.

Hagenbach's defense was simple. He was following orders. His superiors had told him what to do, and he did it.

The tribunal rejected this argument. As a knight, they ruled, he had a duty to prevent criminal behavior by the forces under his command. They found him guilty, condemned him to death, and cut off his head.

Five hundred years before the Nuremberg Trials, before the Geneva Conventions existed, before anyone had coined the phrase "crimes against humanity," this medieval court established a principle that would echo through centuries of warfare: following orders is not an excuse.

What Makes a War Crime?

War is, by its nature, violent. Soldiers kill other soldiers. Buildings get destroyed. Civilians die. So what separates the terrible-but-legal violence of warfare from the violence we call criminal?

The answer lies in a set of principles that have evolved over centuries, now codified in what lawyers call international humanitarian law. At its core, this body of law recognizes something counterintuitive: even in war, there are rules.

A war crime is a serious violation of these rules. Not just any violation—the kind that gives rise to individual criminal responsibility. The perpetrator can be arrested, tried, and punished.

The list of actions that qualify reads like a catalog of humanity's darkest impulses. Intentionally killing civilians. Torture. Taking hostages. Sexual violence. Using child soldiers. Destroying civilian property when military necessity doesn't require it. Ordering mass killings, including genocide or ethnic cleansing.

But perhaps the most important concept is this: causing more harm than military necessity demands. You can destroy an enemy ammunition depot even if a farmer is plowing a nearby field. But you cannot level an entire city to eliminate a single sniper.

The Principle of Distinction

One of the foundational rules of warfare is the principle of distinction. Combatants must distinguish between military targets and civilian objects. They must distinguish between enemy soldiers and non-combatants.

This sounds straightforward until you consider the complexities of modern warfare. What about a factory that makes both civilian goods and military equipment? What about a power plant that serves both a hospital and a military base? What about a building that houses both families and a weapons cache?

The law doesn't require perfection. It requires proportionality. An attack that might kill some civilians can still be lawful if the military advantage gained is significant enough. But there's a limit. If the expected civilian harm is "clearly excessive" compared to the military benefit, you've crossed into war crime territory.

The Fog of War Defense

In 1944, German General Lothar Rendulic ordered his troops to destroy civilian buildings and farmland across Finnish Lapland as they retreated. He believed Soviet forces were about to occupy the region, and he wanted to leave them nothing useful—a strategy called scorched earth.

After the war, Rendulic faced trial for this destruction. His defense? He had assessed the military necessity based on the information available at the time. Yes, he overestimated the threat. Yes, the destruction turned out to be unnecessary. But he couldn't have known that then.

The tribunal acquitted him. This decision established what's now called the Rendulic Rule: commanders must be judged based on what they knew when they made their decisions, not on information that came to light afterward.

This rule matters enormously in modern warfare. When a pilot drops a bomb on what headquarters says is a military target, but it turns out to be a civilian building, who bears responsibility? In the 1999 NATO bombing of Yugoslavia, alliance aircraft struck the Chinese embassy in Belgrade—a civilian object with no military significance whatsoever. But the pilots had been given incorrect targeting information. The investigators concluded that neither the pilots nor their commanders could be held criminally responsible for acting on bad intelligence provided by another agency.

The Birth of Modern War Crime Law

For most of human history, the rules of war existed only as customs and traditions. Soldiers understood that certain things simply weren't done. But there were no international treaties, no formal codes, no tribunals.

That began to change in the nineteenth century.

In 1863, in the middle of the American Civil War, President Abraham Lincoln issued General Order 100. Written by Franz Lieber—a German lawyer, philosopher, and veteran of the Napoleonic Wars—this document became the first attempt to codify the laws of war for a modern army.

The Lieber Code, as it came to be known, defined command responsibility for war crimes. It established the military responsibilities of Union soldiers fighting the Confederate States. It drew lines between legitimate military action and criminal conduct.

Decades later, representatives from nations around the world gathered in The Hague, Netherlands, for two peace conferences—in 1899 and 1907. The resulting Hague Conventions established formal international agreements about the conduct of war. They prohibited certain weapons, protected prisoners and civilians, and created the framework for prosecuting those who violated the rules.

The Geneva Conventions followed. First adopted in 1864, they were expanded in 1929 and again in 1949. Today, every member of the United Nations has ratified them. They represent the legal foundation for the conduct of war under international law.

Victor's Justice

Here's an uncomfortable truth about war crimes: throughout history, the winners have mostly judged the losers.

After World War Two, the Allies established tribunals at Nuremberg and Tokyo to try the leaders of Nazi Germany and Imperial Japan. These trials established crucial precedents—that individuals could be held criminally responsible for violations of international law, that following orders was not a defense, that aggressive war itself could be a crime.

But they also raised troubling questions about fairness.

The attack on Pearl Harbor was declared a war crime at Tokyo. Japan attacked while officially at peace with the United States, without just cause for self-defense. The tribunal ruled this went beyond any justification of military necessity.

Yet the Allies were never prosecuted for their own attacks on cities. The firebombing of Dresden. The Operation Meetinghouse raid on Tokyo—the single most destructive bombing raid in history. The atomic bombings of Hiroshima and Nagasaki.

How did these escape prosecution? The uncomfortable answer: at the time, no international treaty explicitly protected civilians from aerial attack. The law hadn't caught up to the technology. Technically, bombing cities from aircraft wasn't officially a war crime—even though similar destruction by other means would have been.

The Allies never prosecuted German commanders for their bombing raids on Warsaw, Rotterdam, or British cities during the Blitz. They never prosecuted the indiscriminate attacks with V-1 flying bombs and V-2 rockets. If they had, their own bombing campaigns might have faced equivalent scrutiny.

After the war ended, controversy erupted over the treatment of German prisoners. The Allies reclassified many of them from "Prisoners of War" (protected by the 1929 Geneva Convention) to "Disarmed Enemy Forces" (allegedly not protected). Many were then used for forced labor, including the incredibly dangerous work of clearing minefields. By December 1945, six months after hostilities ended, French authorities estimated that 2,000 German prisoners were still being killed or maimed each month in mine-clearing accidents.

The 1949 Geneva Convention was deliberately reworded to close this loophole. Now, soldiers who "fall into the power" of an enemy through surrender or mass capitulation receive the same protections as those captured in active combat.

The Architecture of Accountability

For decades after World War Two, the international community lacked permanent institutions to prosecute war crimes. The Nuremberg and Tokyo tribunals were one-time affairs, established for specific conflicts.

That changed in the 1990s, when brutal conflicts in the former Yugoslavia and Rwanda demanded a response.

The United Nations Security Council established the International Criminal Tribunal for the Former Yugoslavia and the International Criminal Tribunal for Rwanda. These ad hoc courts prosecuted some of the worst atrocities of the late twentieth century, including genocide, systematic rape, and ethnic cleansing.

In 2002, the International Criminal Court came into existence. Established by the Rome Statute, this permanent court has jurisdiction over war crimes, crimes against humanity, and genocide. Article 8 of the Rome Statute provides the most comprehensive modern definition of war crimes, including:

Willful killing of protected persons
Torture or inhuman treatment, including biological experiments
Willfully causing great suffering or serious bodily injury
Extensive destruction of property not justified by military necessity
Compelling prisoners of war to serve in hostile forces
Denying prisoners fair trials
Unlawful deportation or confinement
Taking hostages

In 2008, the Security Council expanded this framework explicitly. Resolution 1820 declared that rape and other forms of sexual violence can constitute war crimes, crimes against humanity, or acts of genocide. Eight years later, the International Criminal Court convicted someone of sexual violence for the first time, adding rape to the war crimes conviction of Jean-Pierre Bemba Gombo, the former Vice President of the Democratic Republic of Congo.

The White Flag and Other Rules of Engagement

Some of the most specific rules of war concern the conduct of combat itself.

The white flag of truce is sacred. Attacking soldiers who display it is a war crime. So is using a white flag to trick enemy forces into lowering their guard, then attacking—a form of treachery called perfidy.

Wearing enemy uniforms or civilian clothes to infiltrate enemy lines is legitimate if you're gathering intelligence. But fighting in combat while so disguised? War crime. Assassinating individuals behind enemy lines while dressed as a civilian? Also a war crime.

Here's a rule that surprises many people: attacking soldiers as they parachute from a disabled aircraft is a war crime. The Geneva Conventions explicitly protect these parachutists while they're in the air and once they land—so long as they surrender. However, this protection doesn't extend to paratroopers being deployed for combat operations. The distinction matters: an ejecting pilot is essentially helpless, while an airborne soldier descending into battle is an active combatant.

Chemical and biological weapons are prohibited by a web of international agreements. The Chemical Weapons Convention and the Biological Weapons Convention establish these bans. Using them isn't just a violation of these specific treaties—it can constitute a war crime under the broader framework of international humanitarian law.

Even spies receive some protection. The 1907 Hague Convention explicitly forbids punishing captured spies without giving them a trial first.

The Gap Between Law and Reality

Reading the carefully worded provisions of international humanitarian law, you might imagine a world where clear rules govern even the chaos of armed conflict. Reality is messier.

Many of the states most frequently engaged in armed conflict have not ratified the most protective provisions. The Additional Protocols to the Geneva Conventions, adopted in 1977 and containing the most detailed protections for civilians and combatants in modern warfare, remain unratified by the United States, Israel, India, Pakistan, Iraq, Iran, and others.

Even when states accept these obligations in principle, enforcement remains sporadic. The International Criminal Court lacks its own police force. It depends on member states to arrest suspects and turn them over. When powerful states or their allies commit apparent violations, prosecution remains rare.

And the fundamental tension identified at Nuremberg persists. The crime of aggressive war—starting an unjust conflict in the first place—may be the greatest crime of all. But proving that a war violates international law, as opposed to being a legitimate exercise of self-defense, requires judgments that rarely command universal agreement.

Why It Matters

The laws of war may seem abstract until you consider the alternative. Without these rules, warfare would have no limits at all. Every weapon would be permissible. Every target would be fair game. Every prisoner could be executed. Every civilian could be enslaved.

The rules don't prevent all atrocities. They don't even prevent most of them. But they establish that certain acts are beyond the pale—that even in humanity's most extreme circumstances, some things remain unacceptable.

And they create the possibility of accountability. The leader who orders mass killings knows that, if his side loses, he may face trial. The soldier who commits torture knows that "following orders" may not save him. The nation that flouts the laws of war knows that its reputation—and its leaders' freedom—may eventually be at stake.

In 1474, a tribunal of the Holy Roman Empire beheaded Peter von Hagenbach for failing to prevent his soldiers' crimes. Five and a half centuries later, we're still grappling with the same questions: What limits apply even in war? Who bears responsibility when those limits are violated? And how do we build a world where the rules actually matter?

The answers remain imperfect. But the questions themselves represent something important—the stubborn human insistence that even in our darkest moments, law and morality cannot be abandoned entirely.