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.

This surprise decision found that the two Serbian secret police leaders had trained, paid and supervised Serb paramilitary combat units that for years carried out widely-publicized war crimes across Bosnia and Croatia. Yet the judges said a conviction required evidence that the leaders "specifically directed" their aid be used to commit war crimes, something critics say virtually no commander is foolish enough to do.

A spokesperson for the tribunal said that Meron, like all judges at the tribunal, declined to comment on specific decisions.

Critics accuse Meron, who was born in Poland and worked as an Israeli diplomat before immigrating to the U.S. in 1977, of pressuring other judges to endorse legal precedents that make it virtually impossible to convict senior commanders for human rights abuses. Defenders say he exerted no such pressure and is being unfairly attacked for decisions reached by a majority of judges in each case.

In an extraordinary breach of protocol, a Danish judge who serves at the tribunal emailed a scathing letter criticizing Meron to 56 lawyers, friends and associates. In the letter, which was leaked to the Danish press, Judge Frederik Harhoff accused Meron of putting "tenacious pressure" on judges to acquit commanders and speculated that U.S. and Israeli military leaders could now "breathe a sigh of relief."

"Have any American or Israeli officials ever exerted pressure on the American presiding judge (the presiding judge for the court that is) to ensure a change of direction?" Harhoff wrote. "We will probably never know."

Before the acquittals were issued, the CIA and some former American military officials submitted letters of support for some of the defendants, citing their close work with the United States during or after the conflict. But U.S. officials denied pressuring Meron or other judges to make the rulings.

The two former tribunal officials said there was no evidence that Meron acted at the behest of American or Israeli officials. Instead, they argued, the judge was implementing his conservative view of international humanitarian law.

"It's about ego," one of the former tribunal officials said. "Leaving his mark on how the law will be interpreted for generations to come."

David Kaye, a University of California at Irvine law school professor who has worked with Meron, said it was unfair to label him "conservative." Kaye said Meron and his peers were interpreting laws crafted by states that wished to limit the court's reach.