The International Court of Justice in the Hague is best thought of as the United Nation’s court or, in simpler terms, the world’s court.
It was set up as a branch of the UN to settle disputes between states and to give advisory opinions on matters of international law.
The UN is made up of member states. If they have disagreements, it is the court’s job to resolve them and pronounce judgment.
It has 15 judges elected from member states by the UN General Assembly and UN Security Council.
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Is that the right place to bring a case about genocide?
Not necessarily, and that is part of what judges must decide.
The court is more used to considering disputes over land, boundaries, and sovereignty, between two member nations
However, it has considered allegations of genocide before.
Ukraine accused Russia of the crime in its invasion in 2022.
But this is South Africa, a third-party country bringing a case about Israel
A precedent has been set for that as well.
In 2019, Gambia brought a case against Myanmar, alleging it had committed genocidal acts against the Rohingya people.
The ICJ is expected to decide whether it does have jurisdiction in this new case being brought by South Africa.
Why is South Africa bringing this case?
South Africa says it is doing so because it is horrified by Israel’s conduct during this war and it must stop.
It hopes not least for an interim ruling that will demand a ceasefire.
But Israel says it is acting for political reasons.
The South African ruling party – the ANC – has long been a close supporter of the Palestinian Liberation Organisation (PLO) and South Africa sees the Gaza conflict as a colonial war with echoes of their own past conflict.
Israel says that is misleading nonsense.
Does South Africa have a case?
The South African case is that Israel has violated the Genocide Convention, to which it is a signatory.
It cites the huge number of Palestinians killed by Israel, and the deliberate restriction on supplies of water, food, fuel and medical supplies imposed by Israel.
And most worryingly for Israel, the inflammatory statements made by senior Israeli officials during the war dehumanising Palestinians and, the South Africans believe, inciting genocide.
What does Israel say in its defence?
The Israeli legal team is not saying much for now, saving it for the court.
But supporters and legal experts say there was no explicit command or programme of action conceived and executed to carry out a genocide – namely the destruction of an entire people.
And they say they have taken measures to avoid civilian casualties, which would be perverse if they were planning to wipe them all out.
Who is likely to win?
Genocide is one of the hardest allegations to prove in a court of law.
It requires a very high bar of proof.
Destroying an entire race or people requires the resources of a state.
South Africa must show that the government of Israel planned the annihilation of the people of Gaza, ordered it, and set in motion actions to achieve it.
Joining the dots between some inflammatory rhetoric and a lot of people dying will most likely not be enough.
So Israel has nothing to worry about?
It is fair to say that even if the court decides it has the jurisdiction to consider the case, reaching a firm conclusion either way will most likely take years.
But it can also make an interim judgement, and for that, the bar is much lower.
South Africa must only prove it is “plausible” that Israel plotted genocide.
For that to stick, the official statements, supply restrictions, and the extraordinary number of dead civilians may be enough.
And what would an interim judgment against Israel mean?
The court could then order action.
That could range from a demand Israel stop its inflammatory rhetoric, to an order that it ceases all military action until the case has been fully considered.
That would put Israel and its backers, the US, in a bind, because they believe the war must go on until Hamas is dismantled.
Would Israel have to comply?
Both America and Russia have ignored ICJ rulings against them in the past.
Israel may try to do the same.
But it would be hard for Israel to continue a war in the teeth of a ruling handed down by a universally recognised court.
And it would still have to live with a reputation tainted by allegations of one of the worst possible crimes.
For a country established in the wake of a genocide against its own people, that would be a very bitter outcome indeed.