Official Secrets Act 1989

1 Security and intelligence

(1) A person who is or has been—

(a) a member of the security and intelligence services; or

(b) a person notified that he is subject to the provisions of this subsection,

is guilty of an offence if without lawful authority he discloses any information, document or other article relating to security or intelligence which is or has been in his possession by virtue of his position as a member of any of those services or in the course of his work while the notification is or was in force.

(2) The reference in subsection (1) above to disclosing information relating to security or intelligence includes a reference to making any statement which purports to be a disclosure of such information or is intended to be taken by those to whom it is addressed as being such a disclosure.

(3) A person who is or has been a Crown servant or government contractor is guilty of an offence if without lawful authority he makes a damaging disclosure of any information, document or other article relating to security or intelligence which is or has been in his possession by virtue of his position as such but otherwise than as mentioned in subsection (1) above.

(4) For the purposes of subsection (3) above a disclosure is damaging if—

(a) it causes damage to the work of, or of any part of, the security and intelligence services; or

(b) it is of information or a document or other article which is such that its unauthorised disclosure would be likely to cause such damage or which falls within a class or description of information, documents or articles the unauthorised disclosure of which would be likely to have that effect.

(5) It is a defence for a person charged with an offence under this section to prove that at the time of the alleged offence he did not know, and had no reasonable cause to believe, that the information, document or article in question related to security or intelligence or, in the case of an offence under subsection (3), that the disclosure would be damaging within the meaning of that subsection.

(6) Notification that a person is subject to subsection (1) above shall be effected by a notice in writing served on him by a Minister of the Crown; and such a notice may be served if, in the Minister’s opinion, the work undertaken by the person in question is or includes work connected with the security and intelligence services and its nature is such that the interests of national security require that he should be subject to the provisions of that subsection.

(7) Subject to subsection (8) below, a notification for the purposes of subsection (1) above shall be in force for the period of five years beginning with the day on which it is served but may be renewed by further notices under subsection (6) above for periods of five years at a time.

(8) A notification for the purposes of subsection (1) above may at any time be revoked by a further notice in writing served by the Minister on the person concerned; and the Minister shall serve such a further notice as soon as, in his opinion, the work undertaken by that person ceases to be such as is mentioned in subsection (6) above.

(9) In this section “security or intelligence” means the work of, or in support of, the security and intelligence services or any part of them, and references to information relating to security or intelligence include references to information held or transmitted by those services or by persons in support of, or of any part of, them.