Since we conclude that the legitimate needs of the judicial process may outweigh the judicial process may outweigh Presidential privilege, it is necessary to resolve those competing interests in a manner that preserves the essential functions of each branch. ...
The expectation of a President to the confidentiality of his conversations and correspondence, like the claim of confidentiality of judicial deliberations, for example, has all the values to which we accord deference for the privacy of all citizens and, added to those values, is the necessity for protection of the public interest in candid, objective, and even blunt or harsh opinions in Presidential decision-making. A President and those who assist him must be free to explore alternatives in the process of shaping policies and making decisions and to do so in a way many would be unwilling to express except privately. These are the considerations justifying a presumptive privilege for Presidential communications. The privilege is fundamental to the operation of Government and inextricably rooted in the separation of powers under the Constitution.
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No case of the Court, however, has extended this high degree of deference to a President's generalized interest in confidentiality. Nowhere in the Constitution, as we have noted earlier, is there any explicit reference to a privilege of confidentiality, yet to the extent this interest relates to the effective discharge of a President's powers, it is constitutionally based.
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In this case we must weigh the importance of the general privilege of confidentiality of Presidential communications in performance of the President's responsibilities against the inroads of such a privilege on the fair administration of criminal justice. The interest in preserving confidentiality is weighty indeed and entitled to great respect. However, we cannot conclude that advisers will be moved to temper the candor of their remarks by the infrequent occasions of disclosure because of the possibility that such conversations will be called for in the context of a criminal prosecution.
On the other hand, the allowance of the privilege to withhold evidence that is demonstrably relevant in a criminal trial would cut deeply into the guarantee of due process of law and gravely impair the basic function of the courts. A President's acknowledged need for confidentiality in the communications of his office is general in nature, whereas the constitutional need for production of relevant evidence in a criminal proceeding is specific and central to the fair adjudication of a particular criminal case in the administration of justice. Without access to specific facts a criminal prosecution may be totally frustrated. The President's broad interest in confidentiality of communications will not be vitiated by disclosure of a limited number of conversations preliminarily shown to have some bearing on the pending criminal cases.
We conclude that when the ground for asserting privilege as to subpoenaed materials sought for use in a criminal trial is based only on the generalized interest in confidentiality, it cannot prevail over the fundamental demands of due process of law in the fair administration of criminal justice.
