United Nations experts had sounded the alarm that Palestinians in Gaza faced a risk of genocide. The Israeli army was battering the coastal enclave, forcing most of the population from their homes and imposing a stringent blockade barring food, water and other supplies from getting in.

More warnings have since followed alongside calls for the international community to act.

Now, as the International Court of Justice (ICJ) is set to hear a case alleging Israel is committing genocidal acts in Gaza, global attention is again focused on what can — or should — be done to stop the war and prevent crimes like genocide.

South Africa, the country that brought the case to the ICJ, invoked in its decision an “obligation to prevent genocide” as a signatory to the United Nations Genocide Convention — something experts say is a critical step in such cases.

“Genocide is seen as having under international law this special character that it’s relevant to everyone,” explained Mark Kersten, assistant professor of criminology and criminal justice at University of the Fraser Valley in Canada.

“What South Africa is saying, amongst many other things, is that it has the obligation to prevent genocide under the Genocide Convention and therefore the obligation to do something about what it sees as genocide in Gaza,” he told Al Jazeera.

The convention

Signed in 1948 in the aftermath of World War II, the Convention on the Prevention and Punishment of the Crime of Genocide — the Genocide Convention — “codified for the first time the crime of genocide”.

It “signified the international community’s commitment to ‘never again’ after the atrocities committed during the Second World War”, the UN says on its website.

Today, 153 countries are parties to the convention, confirming “that genocide, whether committed in time of peace or in time of war, is a crime under international law which they undertake to prevent and to punish”.

States can meet their obligation to prevent genocide in several ways, including by appealing — as South Africa has done — to the ICJ, the UN’s top court.

In its filing, South Africa argued that Israel has not only “failed to prevent genocide”, but it also “engaged in, is engaging in and risks further engaging in genocidal acts against the Palestinian people in Gaza”.

“The acts in question include killing Palestinians in Gaza, causing them serious bodily and mental harm, and inflicting on them conditions of life calculated to bring about their physical destruction. The acts are all attributable to Israel, which has failed to prevent genocide and is committing genocide in manifest violation of the Genocide Convention,” the submission (PDF) reads.

“South Africa is acutely aware of the particular weight of responsibility in initiating proceedings against Israel for violations of the Genocide Convention. However, South Africa is also acutely aware of its own obligation — as a State party to the Genocide Convention — to prevent genocide.”

This goes further than other genocide cases previously heard by the court, said Kersten.

An important precedent, however, was a case (PDF) brought by The Gambia in 2019. It argued that Myanmar was committing genocide through actions “intended to destroy” the mostly Muslim Rohingya minority group “in whole or in part”.

The proceedings are ongoing, and Canada, France, the United Kingdom and other countries late last year filed a joint petition in support of The Gambia’s case.

“This case confirms that any contracting party can bring a case under the Genocide Convention,” said Amanda Ghahremani, an international criminal lawyer and research fellow at the Human Rights Center at the University of California, Berkeley, in the United States. “It doesn’t necessarily have to be a case between the states that are directly involved.”

‘Serious risk’ threshold

In 2007, the ICJ also laid out when states can act to uphold their obligation to prevent genocide, noting that their responsibility does not solely begin “when perpetration of genocide commences”.

“That would be absurd, since the whole point of the obligation is to prevent, or attempt to prevent, the occurrence of the act,” the court said (PDF) in a decision in a case brought by Bosnia and Herzegovina against Serbia and Montenegro over crimes committed in the former Yugoslavia.

Instead, the obligation arises “at the instant that the State learns of, or should normally have learned of, the existence of a serious risk that genocide will be committed”, the court explained.

“From that moment onwards, if the State has available to it means likely to have a deterrent effect on those suspected of preparing genocide, or reasonably suspected of harbouring specific intent … it is under a duty to make such use of these means as the circumstances permit.”

In the Gaza case before the ICJ, South Africa has asked the court to take provisional measures, including to urge Israel to end its attacks on the enclave, punish public incitement of genocide and lift restrictions on aid deliveries to Palestinians in the territory.

Kersten explained that South Africa does not have to immediately prove that genocide is happening to get those measures approved, but rather it must show that there is “a serious risk of genocide” — a lower threshold.

“We may differ on whether Israel as a state is committing genocide or has committed genocide,” he said.

“But we can definitely say, on the basis of all the statements and all of the violence and the starvation and the siege and the blockade and the expulsions and all of these things, that there is a serious risk of genocide, and if there’s a serious risk of genocide, the duty to prevent it exists.

“And that’s, to me, one of the more powerful things that South Africa has said.”

Political will and consistency

Meanwhile, if a state fails to comply with a ruling by the ICJ, the other party can go to the UN Security Council to enforce the decision, explained Ghahremani.

But even that path does not guarantee compliance. Ghahremani noted that the court last year issued (PDF) provisional measures in Ukraine v Russia, ordering Moscow to immediately suspend its military operation as it considered Kyiv’s case. Russia, which holds veto power at the Security Council, rejected the decision.

“In reality, you will see that states do fail to comply with legal rulings, but it’s still really important that an international institution like the ICJ adjudicates these cases and publicly validates international norms,” she told Al Jazeera.

Ghahremani acknowledged that Israel’s “consistent disregard for international law” over the past decades “doesn’t paint a great picture of the international legal system and the enforcement capabilities of international institutions”. Like Russia, the US — Israel’s main ally — also has a Security Council veto.

“There have been many legal interventions in the international sphere related to Israel’s conduct against Palestinians, and yet Israel continues to breach international law. When you see that level of impunity … you do lose a lot of hope in the international legal system to be able to halt and prevent genocide, amongst other atrocities,” she said.

Still, she said lawyers and rights advocates persist with new and creative ways to use international law to get justice and accountability.

“What’s interesting here to me, with this [South Africa] case, is seeing how precedents from the situations in Ukraine and Myanmar — where there was more political will — are now being used in this context,” Ghahremani explained.

“I’m very curious to see how that plays out and whether we’re going to see consistency in the positions that states take and in the positions of these international institutions… That will also be very telling and illuminating for all of us.”