GENEVA — The United States and other countries that used torture in the war on terror seriously damaged respect for basic human rights, an international panel of legal experts said today.

The eight-member panel, led by former Irish President Mary Robinson, said the three-year investigation found the damage to human rights law was more severe than they had expected.

"The United States, one of the world's leading democracies, has adopted measures to counter terrorism that are inconsistent with established principles of international humanitarian law and human rights law," said the panel in its 199-page report.

It appealed to the new U.S. administration of President Barack Obama to take a leading role in restoring respect for human rights.

The report said the U.S. government applies rules of war to situations without armed conflict and that in cases of real combat it "distorts, selectively applies and ignores otherwise binding rules" of international humanitarian law, which includes the Geneva Conventions on the conduct of warfare.

"The panel has no doubt that there is a real and substantial threat from terrorism in different parts of the world and that governments are under a duty to take effective measures to counter that threat," the report said. "That does not mean that well-established principles of international law can or should be ignored."

The report singled out the United States for these actions.

"The U.S. has a major role to play in rolling back the damage done by its treatment of detainees in Abu Ghraib and Guantanamo Bay, but it is clearly not alone," it said.

The panel said, "It was particularly disturbing to learn in many hearings that governments in other parts of the world are relativizing or justifying their own wrongdoing by comparisons with the U.S."