Perhaps the action most likely to trigger a showdown over Bush's repeated claims of executive privilege was last month's House committee vote to launch contempt charges against former White House counsel Harriet Miers. Bush has asserted executive privilege in refusing to let her testify in Congress' probe of the firing of several federal prosecutors.
Legal scholars say executive privilege is an imprecise term asserted by several presidents but never fully settled by the courts. The Miers case, some say, could be a good test of how to balance a president's need for private advice against Congress's need to oversee executive branch actions that might include political abuses.
"There will be more courts," Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., said Friday. "This administration takes a position that no administration has, certainly since Marbury v. Madison, that somehow they are above the law," he said, referring to the 1803 Supreme Court decision establishing judicial reviews.
Bruce Fein, a Washington lawyer who was an associate deputy attorney general in the Reagan administration, fears Congress is not fighting hard enough to parry Bush's claims of executive privilege.
"The Bush administration is close to reducing Congress to wallpaper, when it comes to oversight, if Congress does not respond" more forcefully, he said.
Republicans, he added, may come to regret the precedents that Bush is asserting.
"I tell my Republican friends that Hillary Clinton will be the president some day," Fein said. "They just don't get it."