The U.N. court also significantly reduced the sentences of two other Bosnian Croats who had been convicted of involvement in the 1993 massacres in Ahmici, where more than 100 Muslim civilians, including women and children, were slaughtered.
Relatives of the defendants, watching from the public gallery, hugged each other and cried out in joy when presiding judge Patricia Wald announced the acquittals.
The five appellate judges criticized the prosecutors, calling the indictments "too general and vague," and said the trial court had been "critically flawed" in its assessment of the evidence.
The judgment was a severe setback for Chief Prosecutor Carla Del Ponte, who was in Yugoslavia Tuesday pressing the governments of Serbia and Montenegro to surrender more wanted war crimes suspects in the Balkan wars.
It was the most sweeping ruling yet by an appellate court. The case was one of the first brought to trial by the tribunal, which was created two years before the 1995 indictments. The trial concluded in January 2000.
Deputy Prosecutor Graham Blewitt told The Associated Press the prosecution had "come a long way" since the early indictments and "has learned a lot since then." He said the acquittal will enhance the court's image is fair and impartial.
The judges ordered the immediate release from detention of brothers Zoran and Mirjan Kupreskic and their cousin Vlatko Kupreskic. The two brothers have been in jail in The Hague since their surrender four years ago. They had been sentenced to 10, 8 and 6 years imprisonment respectively.
The appeals court also cut the 15-year sentence of Drago Josipovic to 12 years, and the 25-year sentence of Vladimir Santic to 18 years.
The court said the trial court had accepted the testimony of shaky witnesses who had identified the three Kupreskic relatives as participants in the dawn offensive on Ahmici and the surrounding villages in April 1983.
Prosecutors had built a weak case based on "unreliable witnesses," it said. The trial court had ignored the testimony of at least one witness that could have affected the verdict, and failed to address discrepancies between witness statements. "In doing so, the trial chamber fell into error," it said.
"The cases against them cannot stand," the ruling said. Reading the judgment for more than one hour, Wald said there had been "a miscarriage of justice."
By Anthony Deutsch
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