The Special Tribunal for Ukraine: Turning the Wheels of International Justice

On 15 May 2026 in Chișinău, Moldova, 34 member states of the Council of Europe, plus Australia, Costa Rica, and the EU (as an institutional body), adopted the resolution establishing the Enlarged Partial Agreement on the Steering Committee of the Special Tribunal for the Crime of Aggression against Ukraine. As Ukrainian Minister of Foreign Affairs Andrii Sybiha stated, “The special tribunal has become a legal reality.”

Previously, Poland and Iceland’s April announcement of their readiness to join the agreement to create a Special Tribunal for the Crime of Aggression against Ukraine (Special Tribunal) enabled the minimum number of states necessary for further steps to be taken. Andrii Sybiha remarked on this occasion: “[…] we have officially crossed the bare minimum required by the Council of Europe for member states to put the agreement to a vote.”[3] This next stage was successfully completed with the adoption of the Enlarged Partial Agreement in May. This key text serves as the basis for establishing the Special Tribunal’s administrative committee and funding mechanism. Secretary General of the Council of Europe, Alain Berset, said that “the time for Russia to be held to account for its aggression is fast approaching.”[4] 

The creation of the Special Tribunal marks the beginning of a new era for Ukraine and an important milestone towards upholding international justice.

The Special Tribunal’s Statute has been drafted with great care to ensure its functions are as effective as possible while limiting the political and legal issues arising, in particular, from the fact that Russia is not involved in the mechanism, even though some of its nationals will be tried.[5] The creation of the Special Tribunal marks the beginning of a new era for Ukraine and an important milestone towards upholding international justice. The law Professor, Mathilde Philip, highlighted that, ironically, the Special Tribunal has been established to try a crime originally formulated by the Russian legal expert Aron Trainin.[6] This Soviet representative at Nuremberg convinced the Allies to ensure that senior Nazi officials were tried for having launched an illegal war, an act now called the crime of aggression.

Overcoming the Legal Gap

The International Criminal Court (ICC) is not legally able to examine acts of aggression committed against Ukraine. It is, nevertheless, important to prosecute those in positions of power who made or facilitated the decision to go to war, in violation of the UN Charter. During the creation of the ICC in 1998, the States-Parties decided that the competence to deal with the crime of aggression would be determined by an amendment to the ICC Statute, adopted at the Kampala Conference in 2010.[7] A new article, Article 15bis of the Rome Statute, was added, which allows the exercise of jurisdiction over the crime of aggression, but only in a limited way. Indeed, the ICC has jurisdiction only over individuals who are nationals of, or present on the territory of, a state that has accepted the amendment, or when the United Nations Security Council (UNSC) refers the situation to the Court. However, neither Ukraine nor Russia has ratified this amendment, and Russia would never allow the UNSC to refer the matter to the ICC. Following the annexation of Crimea in 2014, Ukraine submitted a declaration in 2015 to accept the jurisdiction of the ICC over any acts of genocide, crimes against humanity or war crimes that may be committed within the territory of Ukraine since 20 February 2014 onwards.[8] The Prosecutor of the ICC has, nevertheless, noted that this does not apply to the crime of aggression, given the special conditions required to recognise the Court’s competence.[9]

To sue Russia against its acts of aggression, another path was thus needed. A group of politicians and jurists signed a combined statement calling for a “Special Tribunal for the punishment of the crime of aggression against Ukraine.”[10] In fact, this procedure has already been used: the International Criminal Tribunal for Rwanda or the Special Court for Sierra Leone. Even after the creation of the ICC, the ad hoc court mechanism has continued to be used, as in the case of the Special Tribunal for Lebanon.

Ukraine itself supported the idea of creating a tribunal. A Core Group of involved states—mainly European but non-exclusively—was established in 2023 to develop the precise form of a special jurisdiction.[11] On 25 June 2025, Kyiv and the Council of Europe signed an agreement in Strasbourg to establish a Special Tribunal for the Crime of Aggression against Ukraine.[12] Article 1 of the Special Tribunal’s Statute grounds jurisdiction in Ukraine’s sovereign right to prosecute the crime of aggression committed on its territory. Other states will support the effort through participation in the Enlarged Partial Agreement signed in May by 36 states—including non-member states of the Council of Europe—plus the EU. Estonia was the first country whose parliament officially confirmed its readiness to support the Special Tribunal’s administrative functioning and financing in February 2026.[13]

Reliability in the Tribunal’s Statute

The Special Tribunal’s Statute makes numerous references to other international declarations, conventions, and jurisprudence to demonstrate its legitimacy and knowledge of international law.[14] For instance, the definition given of “crime of aggression” in Article 2(1) of the Special Tribunal’s Statute draws extensively from Article 8bis of the Rome Statute but does not replicate it in whole. The detailed list of constitutive acts enumerated in Article 8bis(2) of the Rome Statute is omitted, to instead direct the Special Tribunal to take into account United Nations General Assembly (UNGA) Resolution 3314 (XXIX), which contains that list and other guidance on assessing aggression.[15] Political assessments made by the UNGA, as well as customary law emanating from the Nuremberg and Tokyo Tribunals, will be taken into account by the Special Tribunal to provide a wider scope than that provided for in the Rome Statute.

The Special Tribunal’s Statute also respects the jurisprudence of the European Court of Human Rights (ECHR), such as the Sejdovic vs Italy Case,which recognises the compatibility of in absentia proceedings with the right to a fair trial under Article 6 of the European Convention on Human Rights, as long as procedural guarantees are rigorously upheld and a right to retrial is preserved.[16] Article 28 allows the trial and conviction of an accused who is not present, under several conditions. The authors of the Statute drew on lessons from prior institutional experience, most notably the Special Tribunal for Lebanon (STL), which conducted its main trial and rendered its final judgment in the absence of the accused.[17] Although arguably procedurally compliant with applicable international human rights law, the STL’s in absentia model was widely perceived as lacking sufficient legitimacy, undermining public confidence in its authority and contributing to perceptions of limited deterrence. The Special Tribunal’s Statute reflects a framework informed by that precedent, allowing proceedings to continue in the absence of the accused, but it embeds rigorous procedural protections and avoids any presumption that in absentia trials are a preferred or default mode of ruling.

The Special Tribunal will not be able to hold the incumbent heads of state, heads of government, and foreign ministers, the so-called ‘troika’, accountable.

Another issue the authors had to address was immunity. The Special Tribunal will not be able to hold the incumbent heads of state, heads of government, and foreign ministers, the so-called ‘troika’, accountable. Indeed, under customary international law, such officials enjoy personal immunity (immunity ratione personae) while they are in office. Article 23(5) of the Statute makes clear that when the indictments concern a member of the troika, the procedure shall be suspended until the person no longer holds office or an appropriate waiver has been presented to the Special Tribunal. In this way, the Statute affirms the principle of individual accountability while respecting the jurisdictional limits imposed by international law on the prosecution of sitting troika members, as explained by the International Court of Justice in the Arrest Warrant Case.[18] Personal immunity is only temporary, while functional immunity (immunity ratione materiae) is unlimited. However, it is difficult to shield international crimes behind the veil of official office. Draft Article 7 of the UNILC seems to suggest this by specifically targeting functional immunity in the context of international crimes, thereby allowing it to be waived in such cases.[19] The crime of aggression is, nevertheless, not mentioned as an exception, but the Special Tribunal’s future decisions could enable it to be included in the Commission’s forthcoming work.

It is important for Ukraine that the Special Tribunal is seen as credible and unbiased as possible, in order to further emphasise the difference with the Russian approach. The international community’s recognition and support are crucial to the tribunal’s future influence. Indeed, for these decisions to be effective, they will need to be recognised as widely as possible by other countries. Chapter III, Section 1 of the Special Tribunal’s Statute provides general principles to respect, in accordance with human rights, such as the right to defence, the ne bis in idem principle, and the right to a fair trial. The protection of fundamental rights is, therefore, a key aspect of the future Special Tribunal’s procedures.

A Milestone for International Justice

The next step for the Special Tribunal is June 2026, when the States-Parties meet again to establish the tribunal’s governing body, comprising representatives from all participating states. They have to elect judges, appoint a prosecutor, and approve the Special Tribunal’s budget. Once the judges have been elected and the prosecutor appointed, the first indictments will be issued. The entire procedure may take six months or more. Although this may seem like a long time, it must be acknowledged that the establishment of the Special Tribunal is progressing rapidly and will be able to begin its work in 2027.

A precedent is being set, sending a clear message far beyond Russia’s actions: the crime of aggression will not go unpunished.

Even if some criticism is valid—regarding the partial retention of immunities, the possibility of trying cases in absentia, and the tricky future cooperation with the ICC—the establishment of the Special Tribunal for Ukraine signifies a historic turning point. A precedent is being set, sending a clear message far beyond Russia’s actions: the crime of aggression will not go unpunished, even if justice is pursued in a regional rather than global format due to the ICC pathway being blocked. Indeed, the entire international community will have its eyes fixed on this tribunal, which will thus be under a duty to set an example. To minimise accusations of bias from Russia and counter potential hostility toward international justice mechanisms from powerful states like the US, the Special Tribunal will need to demonstrate that it is fair and that its actions are guided solely by the duty to deliver justice.

[1] Council of Europe, Resolution establishing the Enlarged Partial Agreement on the Management Committee of the Special Tribunal for the Crime of Aggression against Ukraine (Adopted by the Committee of Ministers on 15 May 2026 at the 135th Session of the Committee of Ministers, in accordance with its decision CM/Del/Dec(2026)135/2a), CM/Res(2026)5 (Council of Europe, 15 May 2026).

[2] Ulyana Krychkovska, “Council of Europe approves decision to launch special tribunal for Putin,” European Pravda, 15 May 2026.

[3] Kateryna Serohina, “Iceland and Poland take key step toward tribunal against Ukraine – Ukrainian FM,” RBC-Ukraine, 15 April 2026.

[4] “36 countries approve creation of special Ukraine tribunal to prosecute Russia”, France 24 with AFP, 15 May 2026.

[5] Russia has already introduced asymmetric measures to counter this mechanism, notably with the Duma’s recent adoption in May of a law authorising Vladimir Putin to deploy armed forces abroad to protect Russian citizens facing detention or prosecution by foreign or international courts not recognised by Moscow. See: Sasha Vakulina, “Russian parliament approves law allowing Putin to invade other countries.” Euronews, 14 May 2026.

[6] Mathieu Dejean, interview with Mathilde Philip, “Un tribunal spécial pour juger Vladimir Poutine,” Mediapart, 16 May 2026. 

[7] International Criminal Court, Rome Statute of the ICC (ICC, adopted on 17 July 1998).

[8] “Ukraine Accepts ICC Jurisdiction Over Alleged Crimes Committed Since 20 February 2014,” ICC, 8 September 2015.

[9] Statement of ICC Prosecutor, Karim A.A. Khan QC, “On The Situation In Ukraine: “I Have Been Closely Following Recent Developments In and Around Ukraine With Increasing Concern,” ICC, 25 February 2022.

[10] “A criminal tribunal for aggression in Ukraine,”Calling for the creation of a special tribunal for the punishment of the crime of aggression against Ukraine Statement (Chatham House, 4 March 2022).

[11] “Dmytro Kuleba: Coalition for the establishment of a Special Tribunal for the crime of aggression of the Russian federation against Ukraine will continue to grow,” Ministry of Foreign Affairs of Ukraine, 27 February 2023.

[12] “Agreement between the Council of Europe and Ukraine on the Establishment of the Special Tribunal for the Crime of Aggression against Ukraine,” Council of Europe, 25 June 2025.

[13] “Estonia becomes the first country whose parliament has approved the agreement stablishing the management committee of the Council of Europe’s special tribunal for the crime of aggression,” Ministry of Foreign Affairs of Estonia, 11 February 2026.

[14] Council of Europe, Statute of the Special Tribunal for the Crime of Aggression against Ukraine (Adopted with the Agreement between the Council of Europe and Ukraine on 25 June 2025).

[15] United Nations General Assembly, Definition of Aggression, Resolution 3314 (XXIX). (UNGA, 14 December 1974).

[16] European Court of Human Rights, Case of Sejdovic v. Italy (Application no. 56581/00) (ECHR, 1 March 2006).

[17] For more details: United Nations Security Council, Resolution 1757 (2007) (UNSC, 2007), Agreement between the United Nations and the Lebanese Republic on the establishment of a Special Tribunal for Lebanon, 30 May 2007.

[18] International Court of Justice, Case concerning the arrest warrant of 11 April 2000 (Democratic Republic of the Congo v. Belgium) (ICC, 14 February 2002).

[19] United Nations International Law Commission, Draft articles about immunity of State officials from foreign criminal jurisdiction (United Nations International Law Commission, 2022).

Views expressed in ICDS publications are those of the author(s).