What crimes will the Court try?
The Court has a mandate to try individuals rather than States and to hold them accountable for the most serious crimes of concern to the international community - genocide, war crimes and crimes against humanity, and, eventually, the crime of aggression. A common misperception is that the Court will be able to try those accused of having committed such crimes in the past, but this is not the case. The Court will have jurisdiction only over crimes committed after 1 July 2002*, when the Statute entered into force.
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War crimes include grave breaches of the Geneva Conventions** and other serious violations of the laws and customs that can be applied in international armed conflict, and in armed conflict "not of an international character", as listed in the Statute, when they are committed as part of a plan or policy or on a large scale.
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What about aggression? Isn't it in the Statute?
Aggression has been included as a crime within the Court's jurisdiction. But first, the States Parties must adopt an agreement setting out two things: a definition of aggression, which has so far proven difficult, and the conditions under which the Court could exercise its jurisdiction. Several proposals have been considered. Some countries feel that, in line with the UN Charter and the mandate it gives to the Security Council, only the Council has the authority to find that an act of aggression has occurred. If this is agreed, then such a finding by the Council would be required before the Court itself could take any action. Other countries feel that such authority should not be limited to the Security Council. There are proposals under consideration that would give that role to the General Assembly or to the International Court of Justice, if an accusation of aggression were made and the Security Council did not act within a certain time. In September 2002, the Assembly of States Parties to the Court established a special working group, open to all States, to elaborate proposals for a provision on aggression. ***