46.—(1) A certificate signed by a Minister of the Crown certifying that disclosure of information to the public would, or would be likely to, adversely affect national security is conclusive evidence of that fact.
(2) A certificate under paragraph (1) may identify the information to which it applies by means of a general description and may be expressed to have prospective effect.
(3) A document purporting to be a certificate under paragraph (1) shall be received in evidence and deemed to be such a certificate unless the contrary is proved.
(4) A document which purports to be certified by or on behalf of a Minister of the Crown as a true copy of a certificate issued by that Minister under paragraph (1) shall in any legal proceedings be evidence (or in Scotland, sufficient evidence) of that certificate.
(5) The power conferred by paragraph (1) on a Minister of the Crown shall not be exercisable except by a Minister who is a member of the Cabinet or by the Attorney General, the Advocate General for Scotland or the Attorney General for Northern Ireland.