At stake are two open questions:
- whether the nationals of states parties that do not ratify the amendments may be prosecuted if such individuals commit the crime of aggression on the territory of any state; and
- whether a prosecution for the crime of aggression may go forward when the crime is committed on the territory of a state party that has not ratified the aggression amendments.
One approach relies on the plain language of Article 121(5) of the ICC Statute, which all states now agree governs the aggression amendments. Reflecting the regime set forth in Article 40(4) of the Vienna Convention on the Law of Treaties, this provision asserts that the Court cannot apply statutory amendments to a state party’s nationals or territory if that state party has not ratified them. Article 121(5) reads:
Any amendment to articles 5, 6, 7 and 8 of this Statute shall enter into force for those States Parties which have accepted the amendment one year after the deposit of their instruments of ratification or acceptance. In respect of a State Party which has not accepted the amendment, the Court shall not exercise its jurisdiction regarding a crime covered by the amendment when committed by that State Party's nationals or on its territory.
The second approach—articulated for the first time post-Kampala—is based on the argument that the adoption of the opt-out provision has over-ridden the amendment regime set forth in Article 121(5). The op- out appears in proposed Article 15bis(4), and reads:
The Court may, in accordance with article 12, exercise jurisdiction over a crime of aggression, arising from an act of aggression committed by a State Party, unless that State Party has previously declared that it does not accept such jurisdiction by lodging a declaration with the Registrar.This revisionist position is not supported by the text of the treaty or the amendments; rather, it depends upon the piecing together of snippets of text and the drawing of subtle assumptions from preambular references.
The plain-language reading of 121(5), by contrast, not only finds clear textual support, but it also reflects sound policy by enabling states parties to remain out of the aggression amendments altogether, both from the perspective of the possible prosecution of their nationals for the commission of aggression elsewhere and from the perspective of potential acts of aggression that may be committed on their own territories.
Lodging an opt-out declaration is no substitute for remaining outside the aggression provisions altogether. Such a declaration will only insulate the nationals of the putative aggressor state from prosecution; it will not prevent the Court from asserting jurisdiction over acts of aggression committed on the territory of states parties. There are a number of reasons why a victim state may not want the crime of aggression to be prosecuted before the ICC, not the least of which would be in circumstances in which an investigation or prosecution might antagonize the conditions on the ground. In addition, a victim state may oppose an aggression prosecution before the ICC when the dispute has already been satisfactorily resolved through diplomatic channels or when the process might risk the production of sensitive national security information.
These open issues reflect enduring confusion over how the treaty’s amendment provisions should apply to the codification of the crime of aggression. This confusion, in turn, threatens the very legality of the amendment package. It is important to gain precision on this point so that the world’s legislative bodies can make informed policy choices about the propriety of ratification.
Fortunately, additional post-Kampala discussions involving interested states are proceeding in informal settings in an effort to resolve this open issue in advance of 2017. This will ensure that the aggression amendments enjoy a genuine consensus—rather than just the illusion of consensus—before the first prosecutions commence. Otherwise, the entire aggression package will be subject to challenge in the first contentious aggression cases that appear before the Court. In such event, the interpretive sleights of hand necessary to sustain the revisionist interpretation should not fool the judges when confronted with the plain language of 121(5), the clear intent of the ICC Statute’s founders, and the principle of lenity.
(See here for Jennifer Trahan's response to this post)