In United States v. Nixon (1974), the U.S. Supreme Court unanimously ruled eight to zero that President Nixon did not have an executive privilege to ignore a subpoena from the Watergate special prosecutor to turn over the tapes. Nixon had installed an extensive audio taping system in the White House. The special prosecutor Leon Jaworksi proceeded to indict several individuals. Nixon refused to turn over the tapes, but would provide edited transcripts of numerous tapes. Nixon claimed that as president he did not have to turn over the tapes. The Supreme Court disagreed:

The President’s need for complete candor and objectivity from advisers calls for great deference from the courts. However, when the privilege depends solely on the broad, undifferentiated claim of public interest in the confidentiality of such conversations, a confrontation with other values arises. Absent a claim of need to protect military, diplomatic, or sensitive national security secrets, we find it difficult to accept the argument that even the very important interest in confidentiality of Presidential communications is significantly diminished by production of such material for in camera inspection with all the protection that a district court will be obliged to provide….

To read the Art. II powers of the President as providing an absolute privilege as against a subpoena essential to enforcement of criminal statutes on no more than a generalized claim of the public interest in confidentiality of nonmilitary and nondiplomatic discussions would upset the constitutional balance of “a workable government” and gravely impair the role of the courts under Art. III.