Crime Against Peace

Crime against peace is a category of international criminal liability formally defined in Article 6(a) of the Charter of the International Military Tribunal (the Nuremberg Charter), annexed to the London Agreement of 8 August 1945. It covers "planning, preparation, initiation or waging of a war of aggression, or a war in violation of international treaties, agreements or assurances, or participation in a common plan or conspiracy for the accomplishment of any of the foregoing."

The concept was the most novel of the three Nuremberg offences (alongside war crimes and crimes against humanity), and the Tribunal called it "the supreme international crime" in its 1946 judgment because it contained "within itself the accumulated evil of the whole." Twelve defendants, including Hermann Göring, Joachim von Ribbentrop, and Alfred Jodl, were convicted on counts relating to crimes against peace. A parallel definition appeared in Article 5(a) of the Charter of the International Military Tribunal for the Far East (Tokyo, 1946).

The United Nations General Assembly affirmed the Nuremberg principles in Resolution 95(I) of 11 December 1946, and the International Law Commission codified them in 1950 as the Nuremberg Principles, with Principle VI(a) restating the offence.

In contemporary practice, the offence has largely been absorbed into and renamed the crime of aggression. The Rome Statute of the International Criminal Court included aggression as a listed crime in 1998 but left it undefined; states parties adopted a definition at the Kampala Review Conference in June 2010 (Article 8 bis), and the ICC's jurisdiction over the crime was activated on 17 July 2018.

Key features:

• It targets leadership conduct, not ordinary soldiers — the "leadership clause" limits liability to those who effectively control a state's political or military action.
• It is distinct from jus in bello violations (war crimes), which concern conduct during hostilities rather than the decision to resort to force.
• It presupposes a breach of the jus ad bellum, particularly Article 2(4) of the UN Charter.