Over the last eight months, a series of surprise rulings at the international war crimes tribunal for the former Yugoslavia has sparked extraordinary controversy in the staid world of international law.

Critics say the decisions weakened World War II-era precedents that hold commanders responsible for war crimes. Supporters say their impact is being exaggerated and the judge associated with them is being unfairly maligned.

In interviews, two former tribunal officials said the decisions reversed years of progress in the field and endangered the recent war crimes convictions of former Liberian President Charles Taylor. They said they feared that the United States and Israel pressured judges to reverse precedents that could limit both countries’ counter-terrorism operations.

“We are taking steps back,” said one of the former officials.

The epicenter of the controversy – and a mystery –  is Judge Theodor Meron, the 83-year-old president of the U.N. tribunal. A holocaust survivor, Meron has worked for decades to create international war crimes tribunals.

But Meron is being harshly criticized for writing recent appeals court decisions that overturned the convictions of two top Croatian and a senior Serbian general for aiding and abetting war crimes. After Meron’s rulings, other tribunal judges acquitted two top Serbian secret police officials, Jovica Stanisic and Franko Simatovic, of aiding and abetting war crimes as well.