The U.S. Supreme Court dealt the Bush administration a major legal setback in connection with the war on terror Thursday. The high court ruled that President Bush had overstepped his authority in ordering military tribunals for terrorism suspects being held at the U.S. Naval base at Guantanamo Bay, Cuba.

US Supreme Court, Washington DC

By a vote of 5-3, the Supreme Court ruled against the Bush administration's plan to use military tribunals to try terror suspects at Guantanamo Bay.

The majority opinion was written by Justice John Paul Stevens, who said the proposed military commissions were illegal under U.S. law and the Geneva Conventions.

In a dissenting opinion, Justice Clarence Thomas wrote that the decision would sorely hamper the president's ability to confront and defeat a new and deadly enemy.

The legal challenge to the tribunals was brought to the high court by lawyers for Salim Ahmed Hamdan. Hamdan worked as a driver and bodyguard for Osama bin Laden and was to go on trial before a military tribunal on a charge of conspiracy.

One of Hamdans lawyers, Professor Neal Katyal of Georgetown University Law School in Washington, spoke outside the Supreme Court.

"It is certainly the case that the president has pushed the bounds of executive authority more so than previous presidents and the ruling today sounds a cautionary note in that regard," he said.

Geroge Bush during a news conference at the White House, June 29, 2006

There was quick reaction to the decision from President Bush as well during a news conference with Japanese Prime Minister Koizumi at the White House.

"We will seriously look at the findings, obviously, and one thing I am not going to do, though, is that I am not going to jeopardize the safety of the American people," he said. "I understand we are in a war on terror, that these people were picked up off a battlefield and I will protect the people and at the same time conform with the findings of the Supreme Court."

Thursday's Supreme Court decision dealt specifically with the issue of the military tribunals and did not address the question of the administration's right to hold the roughly 450 detainees now being held at Guantanamo or what should become of the detention camp there.

US soldier in guard tower over looking military-run Camp Delta prison in Guantanamo Bay US Naval Base, June 27, 2006

But lawyers for the detainees and longtime critics of Guantanamo took heart from the high court's ruling.

"This is a real victory for the rule of law and a clear assertion of the Supreme Court's own continuing role to police the role of the president in carrying out the war on terror," said Deborah Pearlstein, who is with Human Rights First.

The detention camp at Guantanamo Bay has become the focus of international criticism and even President Bush said recently he would like to close it down if he could find a way to keep dangerous terrorists in custody.

Thursday's decision was the second major Supreme Court ruling against the Bush administration's legal approach to those detained on the battlefield as part of the war on terror.

Two years ago, the high court rejected the president's claim to being able to hold terror suspects indefinitely without giving them access to lawyers and the U.S. civilian court system.

Legal analysts and members of Congress are already considering the impact of the Supreme Court ruling.

John Warner (file photo)

Republican Senator John Warner of Virginia says some of the cases involving suspected terrorists at Guantanamo may wind up in the U.S. civilian court system.

"We might look to the federal [court] system and other means by which to provide that. But there also could be an acceleration of efforts to return them to their native countries, to the extent those countries will accept them," he said.

Only eight of the nine Supreme Court justices took part in Thursday's ruling.

Chief Justice John Roberts did not participate because he had ruled in favor of the Bush administration on the issue when he was a federal appeals court judge prior to his appointment to the Supreme Court.

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