The court said Dario Kordic, a leader of the nationalist Croatian Democratic Union and of the Croatian Defense Council, helped plan and organize a campaign to drive Muslims from an area the Croats wanted to join to the newly created state of Croatia. Kordic, 40, was sentenced to 25 years imprisonment.
The tribunal also convicted Mario Cerkez, 41, a Croat military commander, of war crimes in leading attacks against Muslim villages during the Bosnian war in 1993-94. He received a 15-year sentence.
Kordic, a politician, was found innocent of being among those who set the policy of ethnic cleansing, but was "enthusiastic" in carrying out the campaign "and played an instrumental part," the judgment said.
"You played your part as surely as the man who pulled the trigger," May told Kordic.
The worst of the massacres was in Ahmici on April 16, 1993, when Croatian militiamen stormed into Muslim homes. Entire families were gunned down and houses set ablaze. Survivors of the bullets were burned alive.
Before the attack, 356 Muslims and 87 Croats lived in the village. Immediately afterward, no Muslims remained. Croat homes were left untouched.
The court found that Kordic was involved in planning that raid.
Kordic and Cerkez were charged with a total of 44 counts of murder, persecution, plunder and other war crimes or crimes against humanity, and could have been sentenced to life imprisonment. But the court found that their responsibilities were less than described by the prosecution during the 20-month trial.
Kordic was convicted on 12 counts, and Cerkez on 15. The more than three years they have been in custody will be counted toward their terms, the court said.
Both suspects turned themselves in to the tribunal in 1997, two years after being indicted.
The proceedings against Kordic, the most influential political figure brought to trial, were seen as a test case for political responsibility for atrocities on the battlefield.
But the court was cautious in applying the rule of command responsibility against him. It said Kordic was not in "the highest echelons" of policymking, and he "did not possess the authority to stop the crimes or punish the perpetrators."
Both men were found to have organized "a pattern of plunder" in which mosques were deliberately targeted.
As part of an "ethnic cleansing" campaign, Bosnian Croat forces murdered hundreds of Muslims from a string of villages, used women and the elderly prisoners as human shields during enemy bombing raids and forced thousands of others to flee, the indictment says.
Prosecutors say the massacres were so effective and systematic that they effectively destroyed or removed almost the entire local Muslim population.
"The number of dead may never be known," May said, but they were surely in the hundreds, with thousands more expelled.
The tribunal, established in 1993 to try those responsible for atrocities in the Balkans, has publicly indicted 98 individuals. Some of those still at large include former Yugoslav President Slobodan Milosevic, ex-political leader Radovan Karadic and military chief Ratko Mladic.
By Anthony Deutsch
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