Following our extended series on the crime of aggression and the recently concluded ICC Review Conference, this post discusses several "understandings" added to the final package of amendments concerning the definition of the crime of aggression and its impact outside the Court.
By the time the Review Conference opened in Kampala, delegates had arrived at a consensus definition of the crime of aggression that was loosely based on General Assembly Resolution 3314 but contained subtle yet significant departures from that text. As it turned out, the definition was the only component of the initial Conference Room Paper that was entirely unbracketed. Even the so-called P-2 (France and the United Kingdom) had accepted the definition prior to Kampala, although in a later intervention, France insisted that its approval was tied to the existence of a Security Council filter.
In prior diplomatic meetings and again in Kampala, the United States made overtures to revisit the definition of aggression, but achieved little traction. Delegates were simply too invested in the definition and its provenance to reopen the debate at such a late date. In its second formal intervention (above, photo mine), the United States stated its view that the definition itself was “flawed” and that the apparent consensus on the definition of the crime may actually mask significant disagreements. At the same time, it acknowledged that it might be possible to address these concerns without revisiting the definition itself.
From that point, the United States focused on achieving key “understandings” to be inserted into the amendment package at Annex III, which contained a number of other draft and consensus understandings. These understandings sought to
- reshape the definition and its future interpretation to a certain degree,
- tie the definition more closely to Resolution 3314—from which it derived—and to the UN Charter framework governing lawful uses of force, and
- preserve an opening for claims about the legality of humanitarian interventions and other arguably legitimate yet potentially unlawful uses of force.
- language on complementarity and jurisdictional competence (deemed Understanding 4bis),
- an understanding addressed to the threshold for prosecution (deemed Understanding X), and
- an understanding mandating the cumulative interpretation of the factors of character, gravity, and scale in determining whether an act of aggression had occurred (deemed Understanding Y).
It is understood that the amendments address the definition of the crime of aggression and the conditions under which the Court shall exercise jurisdiction with respect to this crime for the purpose of this Statute only. The amendments shall, in accordance with article 10 of the Rome Statute, not be interpreted as limiting or prejudicing in any way existing or developing rules of international law for purposes other than this Statute. The amendments shall therefore not be interpreted as creating the right or obligation to exercise domestic jurisdiction with respect to an act of aggression committed by another State.
- the addition of a reference to “act of aggression” in the first sentence alongside “crime of aggression;”
- the inclusion of an assertion that the aggression amendments do not constitute a definition of these terms under customary international law; and
- a separation of the third sentence into a separate understanding (and a removal of the word “therefore”) to reflect the fact that it raises a different issue than the first two sentences of this text (definition versus jurisdictional competency).
The proposed language in 4bis met with little discussion or resistance, although ultimately the words "customary international law" were not included. Professor Kress forwarded the new language of Understanding 4bis to the Chair of the Working Group and it later appeared as follows in a Conference Room Paper:
4bis: Domestic jurisdiction over the crime of aggression
It is understood that the amendments that address the definition of the act of aggression and the crime of aggression do so for the purpose of this Statute only. The amendments shall, in accordance with article 10 of the Rome Statute, not be interpreted as limiting or prejudicing in any way existing or developing rules of international law for purposes other than this Statute. It is understood that the amendments shall not be interpreted as creating the right or obligation to exercise domestic jurisdiction with respect to an act of aggression committed by another State.
Very few states have a definition of aggression on the books. (The best study of this topic was done by Astrid Reisinger Coracini of the University of Graz (left), who attended the Kampala Conference on behalf of Austria.) Most of these definitions appear, perhaps not surprisingly, in the penal codes of the states of central Asia and Eastern Europe. Most statutes pre-date the ICC and are loosely premised on the definition of crimes against the peace in the Nuremberg/Tokyo Charters, are denominated as waging or planning a “war of aggression," or contain no definition whatsoever. Most do not subject the crime to universal jurisdiction, but rather premise domestic jurisdiction on principles of territoriality or nationality. Beyond the immediate post-WWII period, there is very little domestic jurisprudence on the crime of aggression, as we've discussed.