Secrets of State and Other Official Information
(1) Secret of state. A "secret of state" is a governmental secret relating to the national defense or the international relations of the United States.
(2) Official information. "Official information" is information within the custody or control of a department or agency of the government the disclosure of which is shown to be contrary to the public interest and which consists of: (A) intragovernmental opinions or recommendations submitted for consideration in the performance of decisional or policymaking functions, or (B) subject to the provisions of 18 U.S.C. §3500, investigatory files compiled for law enforcement purposes and not otherwise available, or (C) information within the custody or control of a governmental department or agency whether initiated within the department or agency or acquired by it in its exercise of its official responsibilities and not otherwise available to the public pursuant to 5 U.S.C. §552.
(b) General rule of privilege. The government has a privilege to refuse to give evidence and to prevent any person from giving evidence upon a showing of reasonable likelihood of danger that the evidence will disclose a secret of state or official information as defined in this rule.
(c) Procedures. The privilege for secrets of state may be claimed only by the chief officer of the government agency or department administering the subject matter which the secret information sought concerns, but the privilege for official information may be asserted by any attorney representing the government. The required showing may be made in whole or in part in the form of a written statement. The judge may hear the matter in chambers, but all counsel are entitled to inspect the claim and showing and to be heard thereon, except that, in the case of secrets of state, the judge upon motion of the government, may permit the government to make the required showing in the above form in camera. If the judge sustains the privilege upon a showing in camera, the entire text of the governments statements shall be sealed and preserved in the courts records in the event of appeal. In the case of privilege claimed for official information the court may require examination in camera of the information itself. The judge may take any protective measure which the interests of the government and the furtherance of justice may require.
(d) Notice to government. If the circumstances of the case indicate a substantial possibility that a claim of privilege would be appropriate but has not been made because of oversight or lack of knowledge, the judge shall give or cause notice to be given to the officer entitled to claim the privilege and shall stay further proceedings a reasonable time to afford opportunity to assert a claim of privilege.
(e) Effect of sustaining claim. If a claim of privilege is sustained in a proceeding to which the government is a party and it appears that another party is thereby deprived of material evidence, the judge shall make any further orders which the interests of justice require, including striking the testimony of a witness, declaring a mistrial, finding against the government upon an issue as to which the evidence is relevant, or dismissing the action.