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Twenty years after war in Croatia catapulted Goran Hadzic from warehouse worker to rebel Serb president, he is in the dock in the final trial of the tribunal set up to prosecute war crimes committed during the bloody conflicts in the former Yugoslavia.

His trial, in its second day Wednesday, underscores that international courts, often maligned for their failure to get suspects into custody, can bring to justice once-untouchable leaders accused of atrocities — given time and support from the international community.

Hadzic, an ethnic Serb, was arrested last year in northern Serbia after more than seven years on the run and has pled not guilty to involvement in the murder of hundreds of Croats and expulsion of tens of thousands more from their homeland. He is the last of the 161 suspects indicted by the Yugoslav tribunal to go on trial.

Param-Preet Singh of Human Rights Watch said the Hadzic trial is "the beginning of the end" for the tribunal, which is aiming to close its doors as it completes its final trials in coming years.

The fact that it took 20 years to reach the court's last trial, "is a good reminder that justice takes time, but it does catch up with perpetrators once states are willing to back it up," Singh added.

The International Criminal Tribunal for the Former Yugoslavia was the first war crimes court set up since the aftermath of World War II and helped lay the legal foundations for the permanent International Criminal Court.

The court has convicted 64 suspects, acquitted 13, sent 13 for trial in local courts and withdrawn indictments against 36, including 16 who died after being charged. Eighteen suspects are on trial and 17 are appealing their convictions.

The ICC, meanwhile, has issued 22 arrest warrants but only five suspects — one of them while he appeals his conviction — are in custody a decade after its establishment.

Spokeswoman Nerma Jelacic said Wednesday prosecutors plan to call 85 witnesses to testify against Hadzic and have been granted 175 hours to present their case.

As Hadzic's trial got under way Tuesday, former Bosnian Serb leader Radovan Karadzic began his defense case in a neighboring courtroom. Karadzic's wartime commander, Gen. Ratko Mladic, is also on trial. All three men were arrested in Serbia after years as fugitives from international justice.

Analysts say international pressure on Belgrade, which was blocked from European Union membership until it arrested all fugitives indicted by the tribunal — a policy known as conditionality — was key in getting the likes of Karadzic and Mladic into custody.

"It just goes to show that conditionality can deliver results when states stand firm and maintain pressure. It's not rocket science," said Singh.

The tribunal's president, Theodor Meron, conceded at the United Nations this week that the court was "little more than an ideal" when it was set up in 1993, "an expression of the outrage of the international community at the atrocities that were being broadcast on television screens" from the bloody Balkan wars.

But Meron said that from its humble beginnings the court had helped forge a new global legal order for perpetrators of atrocities in which, "the question is not if but when and where they will be called to account."

In many cases, the "where" is hoped to be the International Criminal Court, currently housed in a telecom company's former headquarters on the eastern outskirts of The Hague.

Like the Yugoslav court, it has no police force and has to rely on national police forces to arrest suspects.

That is part of the reason the ICC is still waiting for some of its key suspects, including Sudan's President Omar al-Bashir and Ugandan warlord Joseph Kony, to be detained and sent to The Hague for trial.

Singh said the Yugoslav tribunal's success should give the International Criminal Court hope it will eventually get its suspects.

"Sudan is going to be a longer process but these indictments can contribute to a marginalization of these actors which over the long term can ultimately lead to their arrest," she said.

Christophe Paulussen, a senior researcher into international humanitarian and criminal law at the Hague-based T.M.C. Asser Instituut, said he has a wanted poster from the Yugoslav tribunal showing 25 suspects still being hunted in 2000 that was updated in 2011 with the words "No fugitives."

"It is a clear sign that international justice, even though it is not perfect, is functioning," he said.