The International Criminal Court (ICC) recently issued an arrest warrant for Russian President Vladimir Putin for war crimes committed in the abduction of Ukrainian children and their transfer to Russia for adoption by Russian parents. Unfortunately, because of the way the 2010 Aggression Amendment to the Rome Statute is drafted, the ICC cannot prosecute Putin for the crime of aggression. The European Parliament, nongovernmental organizations, academics, and members of the United Nations have made various proposals to create a tribunal to prosecute Russian aggression to fill the gap in the ICC’s jurisdiction.  Ukrainian President Volodymyr Zelenskyy said he favors a hybrid tribunal established by a vote of the U.N. General Assembly.

Last July, the Public International Law and Policy Group (PILPG) made one such proposal in the form of model legislation to establish a Ukraine High Court for War Crimes, which we discussed in Opinio Juris. The model legislation – which PILPG developed in partnership with Ukrainian and international experts, including the law firm Weil, Gotshal & Manges – would create an “internationalized” domestic court modelled on the existing High Anti-Corruption Court of Ukraine to prosecute high-level cases of war crimes, crimes against humanity, and aggression. 

For over a year, the United States appeared skeptical about efforts to address the crime of aggression. But on Mar. 27, U.S. Ambassador for Global Criminal Justice, Beth Van Schaack, announced that the United States supports the creation of an internationalized domestic court in Ukraine to prosecute the Russian crime of aggression. The U.S. proposal hues closely to the model set forth last summer by PILPG and its partners.

Following Ambassador Van Schaack’s announcement, Professor Rebecca Hamilton wrote an essay critiquing the U.S. plan in Just Security. The essay described two downsides to an internationalized domestic tribunal, which we would like to specifically address here.

The Ukrainian Constitution is Not an Insurmountable Obstacle

First, Article 125 of the Ukraine Constitution prohibits the establishment of “special and extraordinary tribunals.” Ukraine judicial experts have explained to us that this provision is intended to prohibit temporary courts created by executive authority.  The prohibition would not likely apply to an internationalized domestic court like the United States is suggesting if created through the normal legislative processes. In 2018, Ukraine established the High Anti-Corruption Court, which includes international advisers of the type envisioned by internationalized tribunal dedicated to prosecuting the crime of aggression against Ukraine. Ukraine could presumably use the same model and legal pathway to create an internationalized tribunal without running afoul of its Constitution. 

While Ukraine is fairly unique in its prohibition of special and extraordinary tribunals, it is worth noting there are ample comparative state practice precedents for creating internationalized domestic courts throughout the globe, including the Regulation 64 Panels of Kosovo, the War Crimes Chamber of the Court of Bosnia and Herzegovina, the Special Department for Adjudicating Trials Against Perpetrators of War Crimes of the Belgrade District Court, and the Iraqi High Court, whose prosecutors were assisted by U.S. Department of Justice attorneys, whose defense counsel were foreign attorneys, and whose judges were assisted by foreign judges associated with the International Bar Association.

Head of State Immunity Would Not Block All Prosecutions for Those Responsible for the Crime of Aggression

Second, there is concern that, unlike a hybrid tribunal created through an agreement between Ukraine and the United Nations General Assembly, an internationalized domestic tribunal would not be able to prosecute the two Russian leaders who may be most responsible for the Russian Aggression – President Vladimir Putin and Foreign Minister Sergei Lavrov – under existing International Court of Justice (ICJ) precedent regarding domestic prosecution of heads of state and foreign affairs ministers. But in announcing the new U.S. policy, Ambassador Van Schaack pointed out that an internationalized domestic court could nevertheless prosecute others responsible for the planning and execution of the crime of aggression against Ukraine. Such persons might include certain members of the Russian parliament,  the Minister of Defense, and the Chiefs of the General Staff. Even if Putin and Lavrov are out of reach, an indictment of such persons for the crime of aggression could be an important symbolic and strategic development. 

Moreover, head of state immunity is a complex legal doctrine and its contours have never been fully tested against a sitting head of state.  In the Belgium Arrest Warrant case, the ICJ stated that head of state immunity does not apply to proceedings before international courts.  What makes a court international enough for this purpose remains an open question. While Ambassador Van Schaack said the United States did not favor an effort to obtain an initial authorization from the United Nations General Assembly because of difficulties in obtaining a sufficiently large majority vote, in response to evolving events on the ground it is plausible that U.N. politics will make it possible to get a General Assembly endorsement after the Court is established, which along with imbedded international advisers might render the institution international enough to pierce head of state immunity under the precedent of the Special Court for Sierra Leone.

In addition, if Putin and Lavrov one day relinquish their positions, they could potentially be tried by an internationalized domestic court since their personal immunity (ratione personae) ends when they leave office, and functional immunity (ratione materiae) may not apply to the crime of aggression. In 1999, the U.K. House of Lords ruled that former Chilian President Augusto Pinochet was not immune from prosecution for the international crime of torture. With no precedent on the application of head of state immunity to former leaders accused of the crime of aggression, it is possible that a former President Putin or a former Foreign Minister Lavrov could be prosecuted in an internationalized domestic court once out of office.  

Ambassador Van Schaak’s announcement was a game changer. As documented in Michael Scharf’s article in the Harvard Journal of International Law, since the conclusion of the Nuremberg trials, the United States had opposed the creation of an international court with jurisdiction over the crime of aggression as well as the use of universal jurisdiction to prosecute the crime in domestic courts. Whatever shape an aggression tribunal ultimately takes, we applaud the new U.S. position which is likely to generate momentum for the prosecution of Russia’s crime of aggression against Ukraine. 

IMAGE: From left, Ambassador-at-Large for Global Criminal Justice Beth Van Schaack, State Department interim spokesman Vedant Patel, Acting Assistant Secretary, Bureau of Democracy, Human Rights, and Labor, and Coordinator for Global Democratic Renewal Under Secretary for Civilian Security, Democracy, and Human Rights Erin Barclay, listens as Secretary of State Antony Blinken speaks at a briefing on the 2022 Country Reports on Human Rights Practices at the State Department in Washington, Monday, March 20, 2023. (AP Photo/Andrew Harnik)