The United Nations has said “there is already clear evidence that war crimes may have been committed” by Hamas and the Israeli military since 7 October and that it is gathering evidence for potential prosecutions.
Which laws apply to the Israel-Hamas war?
All parties involved in the conflict are governed by a body of law drawn from a system of conventions, treaties and war crimes tribunal rulings known as “international humanitarian law” (IHL) or the “law of armed conflict”.
IHL has two key elements. The protection of non-combatants such as civilians or soldiers who have surrendered, and restrictions on the type of warfare employed by a belligerent.
The rules are rooted in treaties going back to the 19th century but these days IHL is built around the 1949 Geneva conventions signed after crimes against humanity committed in the second world war, with a new focus on the protection of civilians. Additional protocols have been added over the years covering the use of certain types of weapons.
There is also case law from various international tribunals, such as the international criminal tribunal that tried the perpetrators of the 1994 genocide of 800,000 Tutsis in Rwanda, which was the first to rule that rape had been used as a weapon of war and genocide.
Israel has not ratified certain protocols in the conventions covering areas such as collective punishments, but the US and other countries regard these provisions as having entered customary international law and therefore binding on all states.
Is there evidence of war crimes in the fighting between Israel and Hamas?
The UN said that Hamas’s indiscriminate killing of hundreds of noncombatants, including children, and the abduction of about 200 others as hostages and human shields in Gaza, is a crime under international humanitarian law.
“Reports that armed groups from Gaza have gunned down hundreds of unarmed civilians are abhorrent and cannot be tolerated. Taking civilian hostages and using civilians as human shields are war crimes,” it said.
Legal experts said that Hamas and other groups such as Islamic Jihad may also be guilty of war crimes for firing thousands of rockets from Gaza into Israel.
The UN also said that Israel may be committing the war crime of collective punishment through its siege of the Gaza territory. The International Committee of the Red Cross agreed.
“The instructions issued by the Israeli authorities for the population of Gaza City to immediately leave their homes, coupled with the complete siege, explicitly denying them food, water and electricity are not compatible with international humanitarian law,” it said.
Amnesty International said it has “documented unlawful Israeli attacks, including indiscriminate attacks, which caused mass civilian casualties and must be investigated as war crimes”.
Human Rights Watch said that “multiple war crimes have been and continue to be committed in Israel and Palestine, with grave concerns that Israeli forces and Palestinian armed groups are carrying out unlawful indiscriminate attacks harming civilians”.
The Palestinian health ministry in Gaza, which is run by Hamas, said more than 8,000 people have been killed in the Israeli assault, including more than 3,000 children.
Some groups have gone further and accused Israel of genocide, although lawyers said that is a harder crime to prove under international law.
Who would prosecute?
The international criminal court (ICC) in The Hague, the permanent court with jurisdiction over war crimes and other crimes against humanity such as genocide, steps in when local jurisdictions fail to prosecute.
The ICC recognised Palestine as a member in 2015. The Palestinians then asked the court to investigate Israel’s assault on Gaza the previous year, and the continued construction of Israeli settlements in the occupied West Bank and East Jerusalem.
The Palestinians have argued that the presence of about 750,000 settlers is in breach of a Geneva conventions requirement that “the occupying power shall not deport or transfer parts of its own civilian population into the territory it occupies”.
Israeli legal and human rights groups also said that Israel is committing the “crime of apartheid” in the occupied territories in breach of international laws specifically barring the practice.
Israel has said it is not subject to the ICC’s authority because it did not sign the Rome statute that established the court and came into force in 2002. The US has backed this position, saying that it “firmly opposes” any investigation on the grounds that “Israel is not a party to the ICC” and that “the Palestinians do not qualify as a sovereign state”.
In response, Fatou Bensouda, then the ICC’s prosecutor, asked the court’s chamber of judges to rule on the issue. The chamber decided that the ICC does have jurisdiction in the West Bank, Gaza and occupied East Jerusalem.
Bensouda then launched a formal investigation after conducting a “painstaking preliminary examination” lasting five years.
“I am satisfied that war crimes have been or are being committed in the West Bank, including East Jerusalem, and the Gaza Strip,” she said.
But after Bensouda left office in June 2021, the ICC went quiet on the investigation.
What is the international criminal court’s stance now?
Karim Khan, the British barrister who is the current ICC prosecutor, visited Gaza’s Rafah border crossing with Egypt on Sunday and said “we have active investigations ongoing in relation to the crimes allegedly committed in Israel on the 7 of October and also in relation to Gaza and the West Bank in our jurisdiction going back to 2014”.
Khan invoked the image of “the terrible gas chambers and the Holocaust, the razing of cities” to argue that governments need to stand behind the international legal architecture that was “built on the rubble of the second world war”.
Khan specifically warned that “there should not be any impediment to humanitarian relief supplies going to children, to women and men – civilians”.
“These rights are part of the Geneva conventions, and they give rise to even criminal responsibility when these rights are curtailed under the Rome statute,” he said.
Khan said the ICC would pursue its investigations with “determination” in the face of Israel’s refusal to cooperate with the court and its block on ICC investigators travelling to the country or the occupied territories.
Khan said he would also investigate “current events in the West Bank”, adding that he was “very concerned also by the spike of the number of reported incidents of attack by settlers against Palestinian civilians”.
Are other countries backing the court’s prosecutor?
Only three countries have formally called for the ICC to become involved: South Africa, Switzerland and Liechtenstein. Micheál Martin, Ireland’s deputy prime minister and foreign minister, said in a radio interview that it was for the ICC to determine if war crimes are being committed.
Human Rights Watch noted that the silence from other countries is in contrast to the wide demands from European governments for the ICC to investigate Russian war crimes in Ukraine.
Does Israel appear worried by talk of an investigation?
Yes, very. When the ICC launched its full investigation in 2021, the prime minister, Benjamin Netanyahu, said Israel was “under attack”.
“The ICC, which was established to prevent a repeat of the horrors the Nazis instigated again the Jewish people, now turns against the state of the Jewish people,” he said. “I promise you we will fight for the truth until we will annul this scandalous decision.”
Israel is worried that its military officials and politicians could be detained under international arrest warrants if they travel abroad and face trial at The Hague.
Israel has typically relied on the US’s protection in international bodies, such as vetoing resolutions at the UN security council. But Washington’s influence over the ICC is limited by the fact that the US has itself refused to sign the Rome statute.
In 2020, President Trump revoked Bensouda’s US visa and imposed financial sanctions on her and another senior prosecutor because of the ICC’s Israel-Palestine investigation and a separate investigation into the US’s actions in Afghanistan.
In response, 67 countries, including close US allies such as the UK, France and Germany, made a statement expressing “unwavering support for the court as an independent and impartial judicial institution”.
Joe Biden has been more cooperative with the ICC, ordering the US to share evidence of Russian war crimes in Ukraine with its investigators. But his administration steadfastly opposes the Israel-Palestine probe.
Even if the ICC were to prosecute Israeli officials, it relies on foreign governments to enforce warrants and arrest the accused. Member countries may well feel obliged to cooperate given the continued support for the court, particularly because of Russia’s crimes in Ukraine.
What about the Palestinians?
Although Hamas’s cross-border attack from Gaza on 7 October was in Israel, it still falls within the ICC’s jurisdiction because the Palestinian armed group operates from within the area under the court’s purview.
But questions remain about the legal status of non-state groups such as Hamas, which is a proscribed terrorist organisation in many countries. After 9/11, the George W Bush administration claimed that al-Qaida and the Taliban were “illegal combatants” and therefore not protected by the Geneva conventions, opening the way for captives to be tortured by the CIA and US military. The US supreme court overturned that interpretation of international law in 2006 and said the Geneva conventions did apply.
Some international legal scholars have said that as Hamas is the de facto governing authority in Gaza, and Palestine has ratified the Geneva conventions, it is bound by their requirements but also protected by them.
The West Bank is partly governed by the Palestinian Authority. Its foreign minister, Riyad al-Maliki met Khan in The Hague last week and effectively endorsed any ICC investigation.
• This article was amended on 31 October 2023 to clarify a reference to the number of “noncombatants” that the UN has said were killed by Hamas in Israel.
