36 CFR § 1256.54
Inter- and intra-agency memoranda (subject to privilege)
November 4, 2020
(a) In accordance with 5 U.S.C. 552(b)(5), NARA may withhold information found in inter-agency or intra-agency records if that information is subject to a legally recognized privilege, including the:
(1) Deliberative process privilege;
(2) Attorney work product privilege; and
(3) Attorney-client privilege.
(b) The Archivist of the United States may determine that this general restriction does not apply to specific records because enough time has passed that release of the information would not result in the harm that the privilege was intended to protect or confidential attorney-client communications.