Because we hold that appellee’s public affidavits sufficed to establish its FOIA exemption claim, we cannot accept appellant’s contention that the District Court was not entitled to review the agency’s nonpublic affidavits
in camera. While
in camera proceedings under FOIA “should be employed only where absolutely necessary,”
Allen v. CIA, 636 F.2d 1287, 1298 n.63 (D.C.Cir.1980), because they are “necessarily conducted without benefit of criticism and illumination by a party with the actual interest in forcing disclosure,”
Vaughn v. Rosen, 484 F.2d 820, 825 (D.C.Cir.1973), cert.
denied, 415 U.S. 977, 94 S.Ct. 1564, 39 L.Ed.2d 873 (1974), this court has recognized that, particularly in national security cases, resort to such proceedings may be necessary or desirable.
Ray v. Turner, 587 F.2d 1187, 1211 n.43 (D.C.Cir.1978);
Phillippi v.
CIA, 546 F.2d 1009, 1012-13 (D.C.Cir.1976). In the instant case, although resort to
in camera affidavits was not strictly necessary, the public affidavits being sufficient to support the agency’s claim, the District Court was within its discretion in recognizing that important rights were at stake, and in wishing to “confirm[ ]” what the public affidavits already indicated. J.A. at 72. Likewise, we find no error in the decision of the District Court to exclude appellant’s counsel from the
ex parte proceedings. In any FOIA case in which considerations of national security mandate
in camera proceedings, the District Court may act to exclude outside counsel when necessary for secrecy or other reasons. In the instant case, this discretion is strengthened by the optional nature of the
in camera proceeding, as noted above. Because the public explanation sufficed, the District Court was free to look at the affidavits
ex parte, and its reasons for excluding appellant’s counsel from such scrutiny — danger to the national security, delay, and ethical considerations — sufficed to justify its decision, particu*974larly as the Court found the presence of appellant’s counsel “not strictly necessary to the resolution of plaintiff’s claim.” J.A. at 75.
See Hayden v. NSA, 608 F.2d 1381, 1385-86 (D.C.Cir.1979), cer
t. denied, 446 U.S. 937, 100 S.Ct. 2156, 64 L.Ed.2d 790 (1980);
Haikin v.
Helms, 598 F.2d 1, 7 (D.C.Cir.1978). See
also Weberman v. NSA, 668 F.2d 676, 678 (2d Cir. 1982), (“The risk presented by participation of counsel ... outweighs the utility of counsel, or adversary process, in construing a [classified affidavit].”) (citation omitted).