Understandably, much of the commentary following the release of the Supreme Court’s blockbuster decision in Trump v. Mazars USA, LLP has focused on the impact of the Court’s ruling on the long-running quest for the President’s tax returns and other financial records.  Buried in the Court’s opinion, however, is an easily overlooked aside regarding the attorney-client privilege that could have significant implications for private parties responding to requests from congressional investigators.

As our colleagues have explored in greater detail elsewhere, congressional investigators have long averred that they are not bound by judge-made common law privileges, including the attorney-client privilege and attorney work product doctrine.  Congress’s steadfast refusal to recognize privilege notwithstanding, serious privilege disputes between Congress and private parties are relatively rare, and the question of Congress’s ability to compel production of privileged material has remained largely unsettled by the courts.  Capitalizing on this uncertainty in the law, congressional investigators frequently rely on the implied or stated threat of a subpoena for privileged material as leverage to obtain sought-after non-privileged documents or testimony.

In Mazars, however, the Supreme Court may have dramatically weakened that leverage and tilted the scale in favor of parties resisting congressional demands for privileged material.  In effect, Mazars represents the Court’s effort to balance Congress’s investigatory prerogatives with countervailing separation-of-powers and related private interests.  In this vein, in discussing the limitations on Congress’s inherent investigative authority, Chief Justice Roberts’s opinion for the Court notes that recipients of congressional subpoenas “have long been understood to retain common law and constitutional privileges with respect to certain materials, such as attorney-client communications.”

In support, the Court points to an account of a famous privilege dispute arising out of the Senate Whitewater investigation.  There, congressional investigators issued a subpoena for notes from a meeting between the Clintons, White House lawyers, and the Clintons’ private counsel.  After a months-long standoff, the Clintons and Congress ultimately reached an agreement under which the Clintons would produce the requested documents in exchange for a concession from the Senate Whitewater Committee that such disclosure would not constitute waiver of attorney-client privilege.  Although the parties thus avoided a direct dispute on privilege, the Mazars Court cited this episode as evidence of a common understanding that parties responding to a congressional investigation have a right to withhold privileged material.

Of course, the question of the applicability of the attorney-client privilege to congressional investigations was not squarely before the Court in Mazars, and the Court’s brief aside on this subject may be easily cast as dicta.  Nonetheless, the Court’s approving recognition of the view that the privilege does apply to Congress will surely prove helpful to parties fighting efforts by congressional investigators to compel disclosure of privileged material.