Dec. 5 (Bloomberg) -- U.S. Supreme Court justices signaled they are divided over a law that bars Guantanamo Bay inmates from challenging their detention in federal court.

The court today in Washington debated whether the 2006 statute, enacted at President George W. Bush's urging, infringed on the constitutional power of the federal courts to consider so-called habeas corpus petitions from Guantanamo inmates.

Justice Anthony Kennedy, who has been the court's swing vote on terrorism cases, directed questions at both sides and didn't tip his hand. Other justices, particularly David Souter and Stephen Breyer, voiced impatience with the government, which has held many of the inmates for almost six years.

``It has been six years,'' Breyer said. ``Habeas is supposed to be speedy.''

The case gives the court a chance to assert a powerful wartime role for the judiciary -- one that even Congress and the president together can't take away. The outcome will help determine the fate of the 300 inmates at Guantanamo's Camp Delta, set up in 2002 to detain accused al-Qaeda fighters captured after the Sept. 11 attacks.

The Bush administration contends that the Constitution and its guarantee of habeas rights don't cover enemy prisoners held outside the country, in this case on Cuban territory that the U.S. occupies under a 1903 lease. Habeas corpus is a legal device that dates back to 14th century England and lets inmates claim they are being wrongfully held.

The cases are Boumediene v. Bush, 06-1195, and Al-Odah v. United States, 06-1196.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net

Last Updated: December 5, 2007 11:53 EST