Crime of aggression in the context of "Crimes against humanity"

International criminal law (ICL) is a body of public international law designed to prohibit certain categories of conduct commonly viewed as serious atrocities and to make perpetrators of such conduct criminally accountable for their perpetration. The core crimes under international law are genocide, war crimes, crimes against humanity, and the crime of aggression.

Classical international law governs the relationships, rights, and responsibilities of states. After World War II, the Charter of the International Military Tribunal and the following Nuremberg trial revolutionized international law by applying its prohibitions directly to individuals, in this case the defeated leaders of Nazi Germany, thus inventing international criminal law. After being dormant for decades, international criminal law was revived in the 1990s to address the war crimes in the Yugoslav Wars and the Rwandan genocide, leading to the establishment of a permanent International Criminal Court in 2001.

In geopolitics, an invasion typically refers to a military offensive in which a polity sends combatants, usually in large numbers, to forcefully enter the territory of another polity, with either side possibly being supported by one or more allies. While strategic goals for an invasion can be numerous and complex in nature, the foremost tactical objective normally involves militarily occupying part or all of the invaded polity's territory. Today, if a polity conducts an invasion without having been attacked by their opponent beforehand, it is widely considered to constitute an international crime and condemned as an act of aggression.

Historically, invasions have variously been associated with conquest and annexation, self-defence (if the invader was attacked first), liberation of the invaded polity's people (or of territory that had been occupied by it), or the establishment or re-establishment of control or authority over a territory. Other common motives include forcing the partition of a polity, toppling or altering the established government of a polity or gaining concessions from said government, or intervening to support a belligerent in a polity's civil war.

An atrocity crime is a violation of international criminal law that falls under the historically three legally defined international crimes of genocide, war crimes, and crimes against humanity. Ethnic cleansing is widely regarded as a fourth mass atrocity crime by legal scholars and international non-governmental organizations (NGOs) working in the field, despite not yet being recognized as an independent crime under international law.

Crimes of aggression are considered by some to be mass atrocity crimes and they are included in the jurisdiction of the International Criminal Court. However, most legal scholars do not consider them to be mass atrocity crimes. While it is certainly a grave violation of international law and frequently the context in which mass atrocity crimes are committed, the crime of aggression is distinguishable because it is an attack on the territory, sovereignty, or political independence of a state rather than on individuals.

The Rome Statute of the International Criminal Court is the treaty that established the International Criminal Court (ICC). It was adopted at a diplomatic conference in Rome, Italy on 17 July 1998 and it entered into force on 1 July 2002. As of January 2025, 125 states are party to the statute. Among other things, it establishes court function, jurisdiction and structure.

The Rome Statute established four core international crimes: genocide, crimes against humanity, war crimes, and the crime of aggression. Those crimes "shall not be subject to any statute of limitations." Under the Rome Statute, the ICC can only investigate and prosecute the four core international crimes in situations where states are "unable" or "unwilling" to do so themselves. The provisions on the crime of aggression did not take effect until after it was defined at the 2010 Kampala Conference.

The International Criminal Court (ICC) is an intergovernmental organisation and international tribunal seated in The Hague, Netherlands. Established in 2002 under the multilateral Rome Statute, the ICC is the first and only permanent international court with jurisdiction to prosecute individuals for the international crimes of genocide, crimes against humanity, war crimes, and the crime of aggression. The ICC is intended to complement, not replace, national judicial systems; it can exercise its jurisdiction only when national courts are unwilling or unable to prosecute criminals. It is distinct from the International Court of Justice, an organ of the United Nations that hears disputes between states.

The ICC can generally exercise jurisdiction in cases where the accused is a national of a state party, the alleged crime took place on the territory of a state party, or a situation is referred to the Court by the United Nations Security Council. As of October 2024, there are 125 states parties to the Rome Statute, which are represented in the court's governing body, the Assembly of States Parties. Countries that are not party to the Rome Statute and do not recognise the court's jurisdiction include China, India, Russia, and the United States.

Territorial integrity is the principle under international law where sovereign states have a right to defend their borders and all territory in them from another state. It is enshrined in Article 2(4) of the UN Charter and has been recognized as customary international law. Under this principle, forcible imposition of a border change is an act of aggression.

In the post-World War years, there has been tension between this principle and the concept of humanitarian intervention under Article 73.b of the United Nations Charter "to develop self-government, to take due account of the political aspirations of the peoples, and to assist them in the progressive development of their free political institutions, according to the particular circumstances of each territory and its peoples and their varying stages of advancement."