Justice in action: Five lessons for Ukraine from the conviction of Kosovo’s former president

On 16 September 2026, a verdict was delivered in The Hague against one of the most prominent political figures in post-war Kosovo. Former Kosovo President Hashim Thaçi and three other former leaders of the Kosovo Liberation Army (KLA) – Kadri Veseli, Rexhep Selimi and Jakup Krasniqi – were found guilty of war crimes committed during the 1998–1999 armed conflict.

Thaçi and Krasniqi were sentenced to 25 years' imprisonment, Veseli to 18 years and Selimi to 13 years. The Court found them criminally responsible for the unlawful or arbitrary detention of 385 people, the torture of 303, the cruel treatment of 49 and the murder of 96 people.

More than a quarter of a century passed between the crimes and this first-instance judgment. During that time, Thaçi went from being one of the KLA's leaders to Prime Minister and later President of Kosovo. Political circumstances, the international environment and institutions all changed. At the time of the war, there was no mechanism capable of providing a legal assessment of these crimes. This differs from the situation in Ukraine, where we are building such a mechanism amid the realities of an ongoing war.

This is one of the most interesting features of the case. The Kosovo Specialist Chambers were established only in 2015. Their structure combines national and international components. The Chambers were established under Kosovo's Constitution and legislation, are integrated into the different levels of its judicial system, and apply Kosovo law alongside international law. At the same time, they are based in The Hague, while their judges, prosecutors and staff are international. The Specialist Prosecutor's Office is also based in The Hague and operates independently of other Kosovo institutions.

In practice, this is a hybrid justice mechanism that combines national jurisdiction with international participation and allows particularly complex cases to be heard outside Kosovo.

In my view, such a model could also be appropriate for Ukraine. This does not, of course, mean replicating the Kosovo model. Ukraine has its own Constitution and judicial system, a significantly greater volume of proceedings concerning international crimes, and an already established system of cooperation with international institutions. At the same time, combining national jurisdiction with international expertise and participation could strengthen Ukraine's capacity to adjudicate the most complex cases while keeping such proceedings within the Ukrainian justice system.

The trajectory of the Thaçi case itself illustrates how long it can take for such an opportunity to emerge. The indictment was confirmed in 2020. Thaçi subsequently resigned as President, was taken into custody and transferred to The Hague. The trial began in April 2023. The evidentiary proceedings concluded at the end of 2025, and in February 2026 the parties presented their closing arguments. The Court heard evidence from 273 witnesses, admitted 5,467 items of evidence, and the trial transcript ran to 29,238 pages.

The indictment contained ten counts. Six concerned crimes against humanity and four concerned war crimes. The outcome of the proceedings was significant not only because of the severity of the sentences imposed.

The accused were acquitted on all counts of crimes against humanity. The Court concluded that the prosecution had failed to prove beyond a reasonable doubt the existence of a widespread or systematic attack directed against a civilian population.

This is precisely why the Thaçi case is far more relevant to Ukraine than simply as the story of one former president. It shows what happens to information about a war decades later, when the political context has already changed and every allegation must withstand judicial scrutiny.

What of the material collected today will withstand such scrutiny in ten, twenty or thirty years? Is it enough to have thousands of documented incidents? Where is the line between information and evidence? How do we move from a specific crime to the responsibility of a particular commander or political leader?

The Thaçi case offers at least five lessons that Ukraine should take into account today.

Lesson One. It Is Necessary to Prove Not Only the Crime, but Also the Responsibility of a Specific Individual

International criminal justice does not put positions or titles on trial.

It is not enough to establish that a person was a commander, minister, general or political leader at the time the crimes were committed.

In the Thaçi case, the Court separately examined the role of each accused, their powers, specific actions, involvement in decision-making and contribution to the common criminal purpose. The Court examined their actual influence. This is fundamentally important for Ukrainian cases concerning Russia's military and political leadership.

A chain of command positions does not in itself establish a chain of criminal responsibility. It is necessary to determine who made decisions, who issued orders, who received reports, who had information about the consequences, what measures were taken after such information was received, and what the actual contribution of a particular individual was to the commission of the crime. This is why proving international crimes requires more than documenting a crime scene. An evidentiary link must be established between a specific incident and a specific individual.

Lesson Two. The Number of Crimes Does Not in Itself Prove the Existence of Crimes against humanity

This is perhaps one of the most important conclusions from the case for Ukrainian investigations.

The Court established that hundreds of people had been victims of murder, torture, cruel treatment and unlawful deprivation of liberty.

Yet this was insufficient to secure convictions for crimes against humanity.

The reason lies in the legal structure of this international crime. It is not enough to prove numerous individual murders, acts of torture or unlawful detentions. The contextual elements must be established separately, including the existence of a widespread or systematic attack directed against a civilian population and the connection between the specific act and that attack.

In the Thaçi case, the prosecution, in the Court's assessment, failed to meet this standard.

For Ukraine, this has direct practical significance. When documenting Russian crimes, it is not enough to accumulate individual incidents. At the same time, material must be collected that makes it possible to identify and prove the broader system: recurring patterns of conduct, their geographical and temporal dimensions, categories of victims, methods of committing crimes, patterns in target selection, command links, orders, internal documents, policies and practices, as well as the leadership's response to crimes of which it was aware.

It is possible to have thousands of well-documented incidents and still have a weak evidentiary basis for establishing the contextual elements of crimes against humanity.

Numbers matter. But arithmetic is no substitute for proof.

Lesson Three. Information Is Not Yet Evidence

Another important aspect of the case concerns information about individuals whom the KLA regarded as opponents.

The Court examined the activities of the KLA's intelligence structures and the role of Kadri Veseli. The judges found that the four accused had made substantial contributions to a common criminal purpose directed against individuals regarded as opponents of the KLA's political and military objectives. These included Kosovo Albanians affiliated with other political or military forces, individuals suspected of links to the Serbian or Yugoslav authorities, and members of national minorities.

For Ukraine, a broader principle is important here.

Intelligence, operational, military or open-source information may be extremely valuable in criminal proceedings. It may help formulate an investigative hypothesis, indicate a direction for the investigation, and assist in identifying witnesses, documents, locations or other sources of evidence.

But information and a proven fact are not the same thing.

For Ukraine, which is currently accumulating a vast body of information about the war, including operational, digital and intelligence data, not least through the work of the newly established Directorate for Documentation of Violations of the Law of Armed Conflict Committed during Hostilities within the Military Law Enforcement Service of the Armed Forces of Ukraine, the question of verification has very practical significance. Such information must be cross-checked against other sources, its provenance and authenticity established, and only then can its evidentiary value be assessed.

Lesson Four. The Legality of War and the Rules Governing Its Conduct Are Assessed Separately

The proceedings in The Hague were not an assessment of the political objectives of the Kosovo Liberation Army or of the idea of Kosovo's independence itself. The Court considered a different question: whether specific individuals bore individual criminal responsibility for specific acts committed during the armed conflict.

This legal distinction is also important for Ukraine. Ukraine is defending itself against Russian aggression, exercising its inherent right of self-defence under the UN Charter. At the same time, international law separately regulates the legality of a state's resort to force and the rules governing the conduct of hostilities.

Accordingly, the legal assessment of a specific incident during the war concerns compliance with international humanitarian law. It neither changes nor calls into question Ukraine's legal status as a state exercising self-defence against armed aggression.

This is why credible information about possible violations by the Ukrainian side must also receive proper legal assessment. This in no way equates the aggressor with the state defending itself. These are different questions of international law and involve different matters to be proved.

Moreover, a state's ability to examine the conduct of its own military personnel and, where sufficient evidence exists, ensure accountability demonstrates the capacity and resilience of its legal system. For Ukraine, this also has very practical significance. Proper domestic investigations allow the state itself to establish the facts, distinguish substantiated violations from unsubstantiated allegations, and examine its own mistakes in order to prevent their recurrence.

This is also important at the international level. Genuine and good-faith criminal proceedings at the national level are relevant to the principle of complementarity on which the jurisdiction of the International Criminal Court is based. At the same time, it protects the state from situations in which third countries initiate investigations under the principle of universal jurisdiction.

There is another aspect that is particularly important in the context of information warfare. If the state itself does not establish what happened in a particular incident, the resulting vacuum is filled by unverified reports and manipulation, which the Russian authorities use to construct their own narrative. A professional investigation helps prevent this.

Legal assessment of possible violations by one's own side therefore demonstrates the ability of the legal system to function even under the most difficult conditions of war, to establish facts regardless of whom they concern, to learn from its own mistakes, and to ensure accountability where evidence exists.

Lesson Five. Evidence Must Outlast the War

More than a quarter of a century passed between the events at issue in the Thaçi case and the first-instance judgment.

But these were not 27 years of a single trial. The trial itself began only in 2023. Before that came years of accumulating information, international investigations, establishing a specialised mechanism, setting up the prosecution office, working with witnesses and preparing the case. The Specialist Chambers were established only in 2015, many years after the events they are now adjudicating.

In 1998, no one could have known that Hashim Thaçi would become Prime Minister, then President of Kosovo, and that two decades later he would leave office and appear before a court that did not even exist at the time of the events.

Likewise, today we do not know what the political circumstances will be in ten or twenty years, or when particular individuals suspected of crimes against Ukraine may actually appear before a court.

But there are things Ukraine can influence now. Will the evidence be preserved? Will it be possible, twenty years from now, to establish its provenance? Will it be clear who obtained a particular digital file or physical object, when and where it was obtained, and under what circumstances? Will the chain of custody be preserved? Will it be possible to reconstruct command relationships and decision-making processes?

The Thaçi case therefore does not provide grounds for mechanically transplanting the Kosovo experience to Ukraine. The conflict is different, the scale is different, the jurisdictional framework is different, and the factual circumstances are different.

But it demonstrates something universal. Political circumstances change far more quickly than the question of individual criminal responsibility disappears. In ten, twenty or thirty years, governments, international relations, official positions and individuals' status may all have changed. A judicial mechanism that does not yet exist today may emerge. New legal avenues for holding particular individuals accountable may become available.

For Ukraine, therefore, the central question today is not only when and where future trials will take place. More important is what we will bring to those trials. Will we have evidence of individual crimes and of their broader context?

The political window for justice may open years from now. More than a quarter of a century passed between the crimes for which Hashim Thaçi and the other KLA leaders were convicted and the first-instance judgment. During that time, political circumstances, individuals' status and institutions changed.

The question of individual responsibility did not disappear.

For Ukraine, this may be the central lesson of the case. Justice may come decades later, but the case that it will one day adjudicate begins today.