The rules of war: The conflict between Israel and Hamas puts international law to the test

Both Hamas and Israel have been accused of violating international law during the conflict unleashed by the former’s surprise attack on the Jewish state on Oct. 7. The UN says it is gathering evidence of war crimes on both sides. Attacks like the one on the Al Ahli al Arabi hospital in Gaza on Tuesday test international law. Enforcing the law in the heat of conflict is difficult, but there are so-called rules of war, which in theory regulate the behavior of the warring parties. Most importantly, they protect the civilian population, which international humanitarian law says should never be a target of war or used as safeguards (human shields) by one of the parties to prevent an enemy attack.

According to local authorities, the attack on the Al Ahli al Arabi hospital in Gaza violates international law. The facility was full of patients as well as people taking shelter from Israeli shelling. Both sides accuse each other of responsibility for the attack: Hamas blames Israel, and Israel claims that the explosion was the result of a failed Islamic Jihad rocket launch.

Accountability for war crimes perpetrators is often elusive, which has led to the establishment of special tribunals such as those in the former Yugoslavia, Rwanda and Sierra Leone. Just three days after Hamas’s October 7 attack on Israel, the UN Human Rights Council announced that one of its independent commissions of inquiry had already gathered “clear evidence” of war crimes perpetrated by both sides. The forced displacement of civilians (as a result of Israel ordering the inhabitants to north Gaza to evacuate), their relocation to the south of the Gaza Strip and the denial of basic supplies (electricity, water, food) for Gazan civilians are also under investigation.

The International Criminal Court (ICC) was established in 2002 and is based in The Hague, Netherlands. It is the only body authorized to prosecute war crimes, international crimes of genocide and crimes against humanity. The ICC recognized Palestine as a member state in 2015. Israel, like the United States, China, Russia and Egypt, is not part of it, so they do not recognize its jurisdiction or abide by its judgments. Former ICC prosecutor Luis Moreno Ocampo said this week that the total blockade of Gaza is a crime against humanity and genocide; as such, the ICC could investigate it.

What are the rules of war?

The rules of armed conflict obey a set of internationally recognized laws and resolutions, including the United Nations Charter, which prohibits wars of aggression but grants countries the right to defend themselves. Conduct on the battlefield is governed by international humanitarian laws, including the Geneva Conventions, which were written after World War II. Almost all nations signed them.

Agreed to in 1949 in the Swiss city, the four conventions establish that civilians, injured parties and prisoners must be treated humanely in wartime. They prohibit murder, torture, hostage-taking and “humiliating and degrading treatment” and require combatants to treat the opposing side’s sick and wounded.

The rules apply to both wars between nations and asymmetrical conflicts, in which one of the parties is not a state, as in the war between Israel and Hamas.

What is a war crime?

A key document in the law of war is Article Eight of the Rome Statute, the founding of the International Criminal Court, which is based on the 1949 Geneva Conventions and defines war crimes as intentional attacks on civilians, civilian settlements or humanitarian workers, destruction of property when not militarily necessary, sexual violence and unlawful deportation.

“Intentionally attacking civilians and civilian targets without a necessary military reason for doing so is a war crime,” explains David Crane, the chief prosecutor of the U.N. Special Court for Sierra Leone, quoted by the AP. “And that is a standard that both sides must meet under international law.”

The legal concept of a “war crime” is separate from the concepts of “crimes against humanity” or “genocide.” While war crimes are limited to conflicts that occur internally or between two states, the latter two can also be committed in times of peace.

Are all attacks on civilians considered war crimes?

This is a controversial question. Classifying a military act as a war crime during a conflict depends on whether or not it was justified. Thus, the bombing of a school or a residential building cannot be classified as a war crime if it is considered militarily necessary. But what about Tuesday’s bombing of a hospital, such as the one attacked — intentionally or accidentally, according to different reports and version s—resulting in hundreds of deaths? According to most experts, it is impossible to bomb Gaza, one of the world’s most densely populated areas, without killing some of the 2.2 million civilians living there. In such circumstances, determining an attack’s intended target is key to establishing whether a war crime has been committed.

What principles should govern the use of force?

The fundamental guiding principle is proportionality, which prohibits parties from responding to an attack with excessive violence. The distinction requires that members of the military constantly try to differentiate between civilians and combatants. In addition, the so-called precautionary principle calls for doing everything possible to avoid harming civilians, and the principle of distinction calls for clearly distinguishing between targets (in short, excluding civilians).

Does the order to evacuate Gaza violate international law?

According to some experts, Israel’s order last Friday for the inhabitants of northern Gaza to move to the south of the Gaza Strip is simply a “precaution” — a warning to avoid harm — but most human rights groups, as well as the UN and the International Committee of the Red Cross (ICRC), believe it does violate international humanitarian law.

“A warning to flee when there is no safe place to flee and no safe way to move is not an effective warning,” the NGO Human Rights Watch criticized Friday. “The Israeli military should issue warnings to civilians in Gaza before an attack if doing so would actually allow them to leave for a safer area.”

The most critical observers claim that this is an attempt at forced displacement bordering on ethnic cleansing, akin to the one that occurred in the Balkans in the 1990s.

Has Hamas committed war crimes?

According to Israel, Hamas’s coordinated attacks on towns and cities have killed 1,400 people; in addition, 199 hostages were taken to Gaza and their whereabouts are unknown. According to the Geneva Conventions, “civilians should never be taken hostage. If that is done, the action can be considered a war crime,” says Jeanne Sulzer, a lawyer for Amnesty International France. Other experts also include the intentional massacre of civilians, such as the ones perpetrated at the music festival and on kibbutzim.

Has Israel committed war crimes?

Most consider Israel’s bombardment of Gaza, the order to evacuate the north Gaza Strip and the deprivation of basic supplies to be “collective punishment” of the area’s two million inhabitants. The International Committee of the Red Cross has stated that the evacuation order, “coupled with a complete siege that explicitly denies them [civilians] food, water and electricity, is not compatible with international humanitarian law.”

The Israeli military claims that it abides by international law and is only attacking legitimate military targets in its attempt to eradicate Hamas militiamen, whom it believes are hiding among the civilian population. Human Rights Watch has accused Israel of using munitions containing white phosphorus. That substance is not banned, but its use in densely populated areas is widely condemned. The Israeli Defense Forces (IDF) denies using it.

How are war crimes investigated?

A United Nations Commission of Inquiry is already “gathering evidence of war crimes committed by all parties.” This evidence could be added to an ongoing ICC investigation into the situation in the Palestinian territories. The ICC can prosecute officials of a country for human rights violations and order compensation for victims, but it does not have a police force to execute arrest warrants; instead, it relies on the police in countries that recognize ICC jurisdiction (Israel does not).

Can victims claim compensation?

While the ICC is the only permanent international tribunal established to prosecute war crimes, other courts, such as the International Court of Justice and the European Court of Human Rights, can prosecute cases of alleged war crimes. Domestic courts in Israel and other countries may also do so. Under U.S. law, American victims could seek to bring claims for compensation against Hamas in U.S. courts. French and dual French-Israeli victims of Hamas attacks have already filed claims in court in France.

Violations of international law can also lead to sanctions, such as those imposed on Russia by the United States, the European Union and other countries for its invasion of Ukraine. In exceptional cases, the UN Security Council can approve UN military intervention, although it can be blocked by the veto of any of its five permanent members, including the United States, Israel’s traditional ally.

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