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It’s a deep honor and a pleasure to address you today as the 6th Ambassador-at-Large for Global Criminal Justice. I was sworn in on March 17th of this year, amidst an extraordinary time of challenges and opportunities in the field of international justice.  My job and the mission of my office is to advise the U.S. government and engage in international diplomacy and programming to help prevent, mitigate, and redress atrocities through justice and accountability.

I’ve been asked today to speak about the crime of aggression in the context of proposals to address this crime as it pertains to Russia’s unjust and brutal invasion of Ukraine. Allow me to briefly recount a history of the crime, a topic I wrote extensively about in my previous role as a legal scholar, and which I have previous experience engaging on as an academic advisor to the U.S. delegation to the International Criminal Court Review Conference in 2010 in Kampala, Uganda. I should note at the outset that my remarks are intended to inform a robust discussion on the proposals for an international tribunal to address the crime of aggression, in the spirit of critical inquiry, and should not be understood as a formal position of the U.S. government on the proposals.

A Short History of the Crime of Aggression

The idea of prosecuting those who launch unjust wars has deep roots, although it was not until the post-World War II era that the international community identified the launching of an aggressive war as a criminal act. In the lexicon of the era, this was deemed a “crime against the peace.” Indeed, it was this crime—rather than genocide—that became the centerpiece of the Nuremberg trial, which was to be the “trial to end all wars.” This pride of place reflected the reasoning, set forth in the Judgment of the International Military Tribunal convened at Nuremberg, that a war of aggression was the proximate cause of all of World War II’s atrocities:

To initiate a war of aggression, therefore, is not only an international crime; it is the supreme international crime differing only from other war crimes in that it contains within itself the accumulated evil of the whole.

  1. Post World War II to Kampala
    Defining and prosecuting a war of aggression, although not uncontroversial, proved relatively easy following the complete defeat of the Axis states in WWII who were  responsible for acts of aggression in World War II. However, when the international community turned its attention to building what would eventually be known as the International Criminal Court, controversies emerged to stymie efforts to codify the crime for more general application in the future.The International Law Commission, the first body to undertake the effort, was unable to agree on a definition of the crime of aggression; this indecision ultimately delayed progress on the ICC project for years. Starting in 1967, the UN General Assembly tasked several special committees to define aggression. This effort eventually led to a consensus definition in General Assembly Resolution 3314 (1974) that was meant to guide the Security Council in implementing its peace and security mandate for “act[s] of aggression” under Article 39 of the U.N. Charter. After a period of Cold War quiescence, the ICC idea was revived and states again sought to define the crime. While influential, the definition of aggression in Resolution 3314 did not easily lend itself to a penal context, so other options were explored. Delegates attending six sessions of Preparatory Committees in 1996–1998 and the 1998 Rome Conference, where the ICC Statute was finally opened for signature, were again unable to agree on the definition of aggression or on a jurisdictional regime to govern the crime’s prosecution.And so, almost everyone agreed to list the crime within the court’s jurisdiction at the last minute, while delaying consideration of the remaining details to a mandatory Review Conference to be convened in seven years. The only guidance the negotiators in Rome offered their successors was the cryptic declaration in Article 5(2) of the ICC Statute that any preconditions for the exercise of jurisdiction over the crime of aggression should be “consistent with the relevant provisions of the Charter of the United Nations.” A series of Preparatory Commissions (1999–2002), Special Working Groups (2003–2009) and informal gatherings held at Princeton University (2004–2007) then took up the task in the period leading up to the planned 2010 Review Conference in Kampala, Uganda.Despite years of multilateral negotiations pre- and post-Rome, delegates arrived at the Review Conference with the most contentious issues still undecided, although the definition of the crime enjoyed a shaky consensus. The perennial difficulty of reaching consensus on when and how to prosecute the crime of aggression stemmed from the recognition that the crime by its nature involves both state action and individual conduct. From virtually the beginning of the negotiations, it was argued that an aggression prosecution should not go forward absent some definitive showing that a state had committed a predicate act of aggression. Where delegations diverged was in deciding which body should be empowered to make this determination: the Security Council, in keeping with its role under the UN Charter as the guarantor of peace and security, or a different body, including perhaps the Court itself. Because state action was a central element of an aggression prosecution, delegates also raised the question of whether it was necessary for some state—the putative aggressor state(s), the victim state(s) or all of the above states—to have consented to the court’s jurisdiction before a prosecution could proceed. Although these two issues—the role of the Security Council and state consent—were present in Rome, they emerged in starker relief in Kampala.

    Indeed, the negotiating dynamics in Kampala were considerably more complex than they had been in Rome, as has been set out at length in various scholarly articles by many of the U.S. participants, including then State Department Legal Adviser Harold Koh, then Assistant Legal Adviser Todd Buchwald, and myself.

    To a certain degree, the story of the aggression negotiations in Kampala is a story about jurisdiction rather than definition. Although all elements of the aggression provisions were open to negotiation in Kampala, the definition of the crime had strong support. Even France and the United Kingdom had ceased their efforts to revise the definition under consideration, although they later argued that their silence should not be construed to indicate support for the text. Accordingly, the negotiations up to and during the Review Conference focused almost exclusively on the jurisdictional regime to govern the crime, although the United States did seek some interpretative understandings to the definition.

    Essentially, the substantive outcome put in place two conditions, under the regime of state consent—a provision allowing for States Parties to “opt out” of jurisdiction; and the complete exclusion of the nationals of Non-Party States absent Security Council referral.

    Once the amendments entered into force, many wondered whether adding the crime to the Rome Statute was purely a symbolic exercise – completing unfinished business dating from World War II, and whether the crime of aggression would ever be prosecuted. I would observe  that one theory underlying the regime of state consent adopted at Kampala, rests on the observation that the crime of aggression implicates state sovereignty more than any of the other three crimes, because a state’s  aggression serves as a predicate for the prosecution of an individual for the crime of aggression. None of the other ICC crimes is so dependent on state action. The perceived exceptionality of the crime of aggression as a function of state action supported arguments in favor of premising jurisdiction on state consent.

  2. The Russian Invasion of Ukraine
    It was against this legal backdrop that Russia relaunched its invasion of Ukraine on February 24, 2022, a date that should live in infamy. It was unequivocally  aggression in manifest violation of the UN Charter. Unlike other contemporary conflicts, this conflict mirrors the archetypal international armed conflict without the complications posed by modern coalition warfare, a splintered opposition, or the participation of transnational terrorist organizations, although Russia has used private military contractors.We are now six months following the full-scale invasion of Ukraine, and President Putin’s war on Ukraine continues to result in climbing costs – thousands of civilians killed or wounded, 13 million Ukrainians forced to flee their homes, historic cities literally pounded to rubble, food shortages, skyrocketing food prices around the world – all because President Putin was determined to conquer another country.  Russia’s premeditated and unprovoked war is a manifest violation of the UN Charter.  The international community has repeatedly condemned the Russian Federation’s flagrant disregard for international peace and security.Furthermore, Russia’s  aggression has been accompanied by war crimes, and there continues to be mounting evidence of war crimes committed in every region where Russia’s forces are deployed. The horrifying litany of atrocities continues to grow: credible reports of Ukrainian citizens killed execution-style with their hands bound; bodies showing signs of torture; video showing civilians being shot in the back without justification; reports of detainee abuse and mutilation, including a video of a POW being castrated; and horrific accounts of gender-based violence, including sexual violence against women and children.  Bombardments hitting densely populated cities, including residential areas, causing thousands of civilian deaths and destroying civilian infrastructure, such as railway stations, rail lines and roads used for evacuations.   Dozens of men, women, and children crushed under a residential building and ripped apart in a recreation center hit by Russian X-22 missiles in Odesa Oblast.  Scores of shoppers in Kremenchuk incinerated by another X-22 missile launched from a Russian long-range bomber.  A seven-year-old girl pulled from the rubble of a Kyiv apartment block, destroyed by a Russian missile as she slept.  Her mother trapped under the building’s rubble for three more hours as rescuers desperately sought to save her.  Three-year-old twins wounded as a Russian missile slammed into their home outside Odesa. Russian missiles struck a music school in Zaporizhzhyia; a Moldovan children’s rehabilitation Center on the Black Sea coast; multi-story apartment blocks in Chernihiv, Dnipro, and Kharkiv; a recreation area and residential area in Mykolayiv; a car service center in Rivne, a hospital, cultural center, library, and school in Sumy; a subway station in Kharkiv; and a lakeside beach in Donetsk. We also have information to suggest that Russian Federation officials are taking steps to conceal Russia’s role in the death of detainees, likely as a result of violent interrogation methods.  There is a growing body of credible evidence that Russia’s forces in Ukraine are torturing and summarily executing Ukraine’s military personnel and noncombatants.The images, videos, and reports compiling witness accounts suggest these atrocities are not the acts of rogue units; they are part of a deeply disturbing pattern of reports of abuse across all areas where Russia’s forces are engaged. And they are consistent with what we have seen from Russia’s military engagements preceding the Kremlin’s further invasion and full-scale war against Ukraine.
  3. Efforts Towards Accountability
    Following a careful review of available information from public and intelligence sources, the United States assessed that members of Russia’s forces have committed war crimes in Ukraine. This was announced in a statement by Secretary Blinken, and in my first week as Ambassador-at-Large for War Crimes, I stepped to the podium of the State Department Press Briefing room to expound on this assessment.The international community, with a strong leadership role by the United States, has swiftly activated a range of accountability mechanisms in the global system of international justice. The United States supports all such international efforts to investigate  and examine atrocities in Ukraine, including the investigation by the International Criminal Court (ICC), the establishment of the UN Commission of Inquiry on Ukraine, the OSCE’s “Moscow Mechanism,” the UN Human Rights Monitoring Mission in Ukraine, and the Joint Investigative Team coordinated through Eurojust. We also welcome proceedings before the International Court of Justice (ICJ) and are tracking Ukraine’s case against Russia before the European Court of Human Rights.And there’s more to report on: recent amendments to Eurojust regulations allowing it to be a repository of evidence of core international crimes; the opening of national investigations in 14 states (and growing), evidencing the deepening state practice regarding the use of universal jurisdiction; the massive collective state referral to the ICC, evidencing enormous international political will; and Ukraine’s adept use of a broad range of legal forums to press its claims under the principle of state responsibility, including two cases at the ICJ (one under CERD and the Convention on Terrorist Financing, and the other under the Genocide Convention), as well as cases before the European Court of Human Rights. All this plus active documentation efforts by international mechanisms and civil society – Ukraine may overtake Syria as the most documented crime base in human history.In addition to supporting these international efforts, my office has deepened and expanded our pre-existing partnership with the Ukrainian Office of the Prosecutor General (OPG). Through a project led by former U.S War Crimes Ambassador Clint Williamson, we have deployed teams of international investigators and prosecutors to assist the Ukrainian Prosecutor General in documenting, preserving, and preparing war crimes cases for prosecution. This work is part of a multilateral initiative, the Atrocity Crimes Advisory Group for Ukraine (ACA), launched with the European Union and the United Kingdom to coordinate support and provide strategic advice and operational assistance to the OPG.

    The ACA consists of a multi-national team of experienced international prosecutors and other war crimes experts deployed now to the region. The initiative consists of two distinct components: the Advisory Board that provides direct advice and counsel to the OPG on international humanitarian law, building case files and prosecuting crimes, and the Mobile Justice Teams that will provide assistance and advice to Ukraine’s investigative and prosecutorial teams on the ground. The ACA is designed to ensure that we deploy our financial means wisely, avoid duplicating our efforts and recruit the best experts in the world to assist the OPG in its challenging, but crucial work as the sole domestic accountability mechanism for grave crimes.

    The Prosecutor General has already identified thousands of incidents that may constitute war crimes—and this without complete knowledge of what is unfolding in areas still under Russia’s control.  We expect that evidence of more atrocities will continue to emerge. International courts and multilateral institutions are complementary to national proceedings.  Ukraine’s OPG is therefore playing a crucial role in ensuring that those responsible for war crimes and other atrocities are held accountable through both its own efforts and in its coordination with multi-lateral institutions.

    The United States is using all of the tools at our disposal to further accountability in a broad sense. To impose costs and promote accountability for malign actors, we have used our sanctions authorities to designate a wide range of individuals and entities; and we have steadily declassified an unprecedented range of information to inform the world of Russia’s actions and counter intense Russian disinformation campaigns. This includes the release of a report by the [ODNI] on Russia’s horrifying “filtration” system–a benign-seeming term that masks a systemic effort that reportedly involves interrogating, abusing, and sometimes deporting, indefinitely detaining, or killing, people who Russia and its proxies perceive as opposed to their control.  The ODNI report assessed that “Russia with the help of proxy groups almost certainly is using so-called filtration operations to conduct the detention and forced deportation of Ukrainian civilians to Russia.”  Secretary of State Blinken released a similar statement on filtration noting that “Estimates from a variety of sources, including the Russian government, indicate that Russian authorities have interrogated, detained, and forcibly deported between 900,000 and 1.6 million Ukrainian citizens, including 260,000 children, from their homes to Russia – often to isolated regions in the Far East.”  In addition to detaining and reportedly torturing some of these individuals, there are reports that “some individuals targeted for “filtration” have been summarily executed…”  We have unsuccessfully called on Russia to immediately halt its systematic “filtration” operations and forced deportations in Russian-controlled and held areas of Ukraine.

    The State Department, led by GCJ’s sibling bureau, the Conflict and Stabilization Office, has established a “Conflict Observatory,” to leverage open-source data, including satellite imagery and social media, to document atrocities committed by Russia’s forces and harm to civilian infrastructure, including to Ukraine’s cultural heritage.  The Conflict Observatory shines a light on atrocities and is intended to contribute to eventual prosecutions in Ukraine’s domestic courts, courts in third-party countries, and other relevant tribunals.

    The Conflict Observatory recently released a new report detailing Russia’s methodical and far-flung “filtration” operations and reported forced transfers and deportations in Russian-controlled  areas of Ukraine.  The unlawful transfer and deportation of protected persons is a grave breach of the Fourth Geneva Convention on the protection of civilians.

    Given the justice and accountability imperatives Ukraine is facing, the U.S. government is investing in multiple lines of effort.  Beyond those outlined above, these include: training and technical assistance for civil society efforts to gather, document, and report on violations of international humanitarian law; expanding access to justice for victims and survivors of atrocities and other abuses; data collection, reporting, and information sharing on human rights abuses and atrocities including through analysis of satellite imagery and other data feeds; forensic assistance focused on the missing and disappeared, laying the foundation for restorative justice; and enhancing the ability of civil society, journalists, and other partners to safely and securely share information.

    Our Department of Justice has also undertaken important accountability efforts. In June 2022, I traveled with Attorney General Garland to the Polish-Ukrainian border, where, during a meeting with the erstwhile Ukrainian Prosecutor General, the Attorney General announced the launch of a War Crimes Accountability Team to centralize and strengthen the Justice Department’s ongoing work to hold accountable those who have committed war crimes and other atrocities in Ukraine.  The Attorney General has appointed Eli Rosenbaum to lead this initiative as Counselor for War Crimes Accountability, a formidable choice given Eli’s long and storied career in identifying, denaturalizing, and deporting Nazi war criminals from the United States.

    A plethora of international NGOs, media, and private citizens are documenting accounts of violations and abuses.  [Great courage and determination are being demonstrated in Ukraine on a daily basis and in many ways by such groups, and the challenges they face in their evidence-gathering and preservation activities in the midst of the brutal war of agression launched by Russia are formidable. These groups play an important role, but their work also carries risks – namely, evidence spoilation and the re-traumatization of victims through well-meaning but less than rigorous methodologies.

    I cannot underscore enough the importance of sustaining international alliances and partnerships and solidarity for the success of these accountability initiatives. All of you in this room know from experience the painstaking work, financial resources, institutional support, challenging legal waters, and diplomatic leadership required to ensure that accountability institutions are effective at delivering on the core mandate of justice.  In July, the United States co-sponsored the Ukraine Accountability Conference in The Hague.  This was a key moment for the international community to reinforce our collective efforts toward accountability for serious international crimes that have been committed in other parts of the world.  Representatives from 45 countries signed a Political Declaration strongly condemning the acts of aggression of the Russian Federation against Ukraine.  The statement notes that Russia’s blatant violations of the Charter of the United Nations threaten international peace and security, gravely damage the rules-based international order, and undermine democratic values.

    We are highly focused on supporting the mechanisms most likely to be effective in bringing perpetrators to justice.    Just as the Allies at the end of the Second World War advanced the imperative of justice and ushered in a new era of accountability for the worst imaginable crimes, it falls to us to ensure that those responsible for war crimes and other atrocities in Ukraine be held to account.  Jurists from the Soviet Union contributed to the very legal architecture used to prosecute those responsible for the gravest crimes at Nuremburg.  Tragically, President Putin has turned his back on this history and on Russia’s international and domestic legal obligations, including under the U.N. Charter and the Geneva Conventions.  Today, we must work together to ensure that the principles of justice and accountability championed at Nuremburg are maintained and strengthened.

    Moscow has taken aim not only at Ukraine, but at the principles of respect for sovereign equality and territorial integrity undergirding peace and security that were enshrined in the U.N. Charter in the wake of two World Wars.  In keeping with those principles, a country cannot change the borders of another by force, subjugate another sovereign country to its will, or dictate another country’s choices or policies.

    The rapidity, scope, and scale of the accountability response is truly unprecedented—and immense work lies ahead in making sure these mechanisms and initiatives are ‘inter-operable’ and maximally effective. Yet despite this, many contend that a juridical gap remains unfilled: [Ukraine’s ICJ case puts Russia’s aggression in issue, but] no international court has jurisdiction over the crime of aggression. This gives rise to a normative question: would atrocity crimes prosecutions be enough to capture the world’s opprobrium? Bearing in mind the expressive function of the law, could atrocity crimes charges alone redress the fundamental breach of international law occasioned by Russia’s blatant war of aggression?

A Tribunal for Aggression?

Which brings us to the various proposals to create a stand-alone international tribunal on aggression. Many of you in this room have contributed to such proposals, draft resolutions, and sample statutes, drawing on your considerable experience and knowledge of potential models. The government of Ukraine has asked the international community to establish such a tribunal on multiple occasions, including in its intervention at the Dutch-led Ukraine Accountability Conference in July.

Turning to the question of how to create such a tribunal, norm entrepreneurs (yes, even legal academics can be entrepreneurs) – are exploring a number of modalities for the creation of such an institution, including: a multilateral treaty that would pool national jurisdiction; an agreement with a regional body such as the EU or the Council of Europe; or an agreement with the UN, particularly given that action at the Security Council is foreclosed by Russia’s veto power. While precedents exist for some of these arrangements – including the Special Court for Sierra Leone, and the Extraordinary African Chambers of Senegal – many outstanding questions and issues remain in this context.  These include foundational questions regarding the authorities such mechanisms could wield, their envisioned efficacy given any limitations in authority, and the sequencing of institutional development.  They also include pragmatic considerations, like funding sources (e.g., voluntary vs. assessed contributions), and challenging legal questions such as the definition of the crime (and whether to include a leadership clause and how to interpret such a clause), the extent of immunities, or whether there should be pendent jurisdiction over other related crimes (such as an act of transnational bombardment that may constitute a war crime itself).

But there is also the essential predicate question of whether this is a necessary and valuable initiative.  There is no consensus at this point in the international community on the merits of a new international tribunal.  A tribunal on aggression would likely focus on political leaders and other decisionmakers, although it is important to note that most of these individuals are located in Russia and unlikely to appear before such a tribunal.  Accordingly, there may be certain limits on what a tribunal can achieve in this context, including with regard to enhancing normative principles of justice.

In addition, there are practical and financial considerations. Right now, our focus has been on maximizing the effectiveness of existing accountability mechanisms.  We are mindful that establishing a new tribunal would require significant resources, and could divert from support to other existing mechanisms, such as the ICC.

I also feel that it is important to recognize the growing perception by many States, especially from the Global South, that the concerted response to accountability for atrocities in Ukraine stands as a stark exception to an inconsistent and uneven response to atrocities in many other parts of the world.  My role as Ambassador-at-Large in the office of Global Criminal Justice – emphasis on the global – is to promote justice and accountability around the world, and as such, I must engage seriously with these perceptions of bias, double standards, and selective justice. To paraphrase my predecessor, Stephen Rapp, when it comes to international crimes, there is only some justice in some places for some people some of the time. All of us here have dedicated our careers to rectifying that reality, recognizing that there must be greater equality in the global distribution of accountability for international crimes.

In addition to the growing perception of bias that undermines the international political unity necessary to ensure the existing accountability mechanisms can successfully deliver, we also need to consider the priorities and needs of victims. This is not a new dilemma for justice advocates. Stephen often recounted that during his time as prosecutor in Sierra Leone he regularly encountered victims with amputated limbs and empty bellies, who supported retributive justice while also noting they could not “eat a court judgment.” We will not shy away from the imperative of justice, but sequencing and prioritization are also important elements. The government of Ukraine, while stating a desire for a mechanism to address Russia’s aggression, has also identified as a priority the need for war reparations and an international claims mechanism for Ukraine.

There are many gaps—including one on reparations and claims—and we must consider our resources and priorities.

It is timely for Ukraine and its partners to be thinking about claims and compensation resulting from Russia’s war against Ukraine.  Overall, we believe that starting to think about setting up some mechanism for registering claims as an initial first step makes sense.  However, there are a number of questions about the goals and practical elements of such a process that would need to be discussed and sorted out.

How do we prioritize efforts to establish a tribunal for aggression alongside other pressing needs?  Have we sufficiently listened to victims about their priorities?

Concluding Remarks and Directives to the Assembled Group

I raise these issues in the spirit of inquisitive neutrality, and a recognition that we must grapple with the complex political, legal, and normative questions around such a proposal. The danger, of course, is that Russia will wait us out; we saw it in Syria and we risk seeing it in Ukraine.  Time is Putin’s greatest weapon, and there is an urgent need to ensure the existing accountability mechanisms deliver on the promise of justice – for the victims and survivors, for the integrity of our cherished values, norms and principles, and for Ukraine.

As I said at the beginning of my remarks, I am not relaying a formal position of the U.S. Government.  The United States is examining these proposals and will continue to discuss them with Ukraine, other states and the international community.  I look forward to a robust dialogue on this topic.

In closing, I “charge” the participants in the Dialogue to examine these issues and questions, report back on the results of their discussion. I look forward to your thoughtful engagement and the discussions that lie ahead.

U.S. Department of State

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