RADOVAN KARADZIC will almost certainly spend the rest of his life in jail. On March 24th the 70-year-old Mr Karadzic was found guilty of genocide and other heinous war crimes by the International Criminal Tribunal for the Former Yugoslavia, based in The Hague. He was sentenced to 40 years in prison.

The leader of the Bosnian Serb side in the Bosnian war of 1992-95, Mr Karadzic is the most senior ex-Yugoslav leader to have been found guilty by the tribunal. His conviction is a landmark for international justice and a warning that leaders who commit appalling crimes face at least the possibility of punishment. Yet in Bosnia, where 21 years have elapsed since the end of the war (and since Mr Karadzic was indicted), the verdict only serves to entrench post-war divisions.

During Yugoslavia’s communist period, Mr Karadzic was a colourful Montenegrin poet and psychiatrist. While living in Sarajevo in 1984 he was arrested on charges of embezzlement, but the case never came to trial. As Yugoslavia began to crumble, he cast about for a political role. After flirting with the green movement he settled on Serbian nationalism, eventually emerging as the leader of the main Bosnian Serb party. In 1992, after Bosnia seceded from what was left of Yugoslavia, his party in turn declared the independence of the Republika Srpska, Bosnia’s Serb-dominated half.

Along with General Ratko Mladic, who led the Bosnian Serb army, Mr Karadzic presided over a murderous campaign of ethnic cleansing. With the support of Serbia, they drove Bosniak Muslims and Croats out of areas they wanted for their ultimate project of a so-called Greater Serbia. After failing to capture Sarajevo, their forces subjected the city to a deadly years-long siege. Towards the end of the war they overran the town of Srebrenica and murdered some 8,000 Bosniak men and boys.

The tribunal found Mr Karadzic guilty on ten of eleven indictments, including the genocide in Srebrenica. He was acquitted on only one count, genocide in other areas of Bosnia at the beginning of the war. Mr Karadzic claimed the numbers killed in Srebrenica were in the hundreds, and said he was legally responsible for nothing, though he did acknowledge “moral responsibility”. The Serbs had only defended themselves during the war, he argued. General Mladic is still on trial.

By the end of the war 100,000 were dead, about half of them civilians. Of those, 82% were Bosniaks, 10% Serbs and 6.5% Croats. Many Serbs see the tribunal as a political kangaroo court.

In the early years after the war the NATO forces that had come to pacify Bosnia refrained from arresting Mr Karadzic for fear of provoking political violence. When they did decide to apprehend him, he vanished. He was eventually arrested in 2008 on a bus in Belgrade, having grown a bushy beard and transformed himself into a spiritual healer going by the name of Dragan Dabic. (He told people his topknot acted as a radio receiver and insisted on protecting bees, which he claimed were “blessed living beings”.) After his arrest Mr Karadzic promptly chopped off the topknot, shaved the beard and returned to the persona familiar from his years in politics.

The Yugoslavia tribunal was the first of a series of international courts established since the 1990s in an attempt to replicate the post-war justice administered by the Nuremberg trials after the second world war. It has played a pioneering role in international justice. The tribunal indicted 161 people; while some had their cases withdrawn and others died before they could be remanded, the rest have all faced trial. (Slobodan Milosevic, Serbia’s leader during the war, died of a heart attack in his prison cell in The Hague in 2006 before the court could render a verdict in his trial.) The court has laid down precedents adopted by other international tribunals, such as those on Rwanda and Sierra Leone as well as the permanent International Criminal Court. Yet on one key issue, the doctrine of command responsibility (under which commanders can be sentenced for crimes committed by their subordinates), it has recently tightened its standards of proof in ways that critics argue make it difficult to convict some of the most senior accused war criminals. While Mr Karadzic was found guilty, others have been acquitted.

One of the Yugoslavia tribunal’s aims was to promote reconciliation in the region. In this it has failed. On March 20th Milorad Dodik, the current president of the Republika Srpska, dedicated a student dormitory in honour of Mr Karadzic in Pale, the small town that served as his self-proclaimed capital during the war. Mr Dodik openly states that he wants to finish what Mr Karadzic started: the destruction of the state of Bosnia.