It is hardly news that top officials in the current Justice Department flout the law and make false statements to Congress, but the latest instance may be the most egregious. When Attorney General Alberto Gonzales wanted the USA Patriot Act renewed in the spring of 2005, he told the Senate, “There has not been one verified case of civil liberties abuse.” But The Washington Post reported yesterday that just six days earlier, the F.B.I. had sent Mr. Gonzales a report saying that it had obtained personal information it should not have.

This is hardly the first time Mr. Gonzales has played so free and loose with the facts in his public statements and Congressional testimony. In the United States attorneys scandal — the controversy over the political purge of nine top prosecutors — Mr. Gonzales and his aides have twisted and mutilated the truth beyond recognition.

Congress and the American public need to know all that has gone on at the Justice Department. But instead of aiding that search for the truth, President Bush is blocking it, invoking executive privilege this week to prevent Harriet Miers, the former White House counsel, and Sara Taylor, a former top aide to Karl Rove, from telling Congress what they know about the purge of federal prosecutors.

Mr. Bush’s claim is baseless. Executive privilege, which is not mentioned in the Constitution, is a judge-made right of limited scope, intended to create a sphere of privacy around the president so that he can have honest discussions with his advisers. The White House has insisted throughout the scandal that Mr. Bush — and even Mr. Gonzales — was not in the loop about the firings. If that is the case, the privilege should not apply.