Justice and Security Act 2013

2 Main functions of the ISC

(1) The ISC may examine or otherwise oversee the expenditure, administration, policy and operations of—

(a) the Security Service,

(b) the Secret Intelligence Service, and

(c) the Government Communications Headquarters.

(2) The ISC may examine or otherwise oversee such other activities of Her Majesty’s Government in relation to intelligence or security matters as are set out in a memorandum of understanding.

(3) The ISC may, by virtue of subsection (1) or (2), consider any particular operational matter but only so far as—

(a) the ISC and the Prime Minister are satisfied that the matter—

(i) is not part of any ongoing intelligence or security operation, and

(ii) is of significant national interest,

(b) the Prime Minister has asked the ISC to consider the matter, or

(c) the ISC’s consideration of the matter is limited to the consideration of information provided voluntarily to the ISC (whether or not in response to a request by the ISC) by—

(i) the Security Service,

(ii) the Secret Intelligence Service,

(iii) the Government Communications Headquarters, or

(iv) a government department.

(4) The ISC’s consideration of a particular operational matter under subsection (3)(a) or (b) must, in the opinion of the ISC and the Prime Minister, be consistent with any principles set out in, or other provision made by, a memorandum of understanding.

(5) A memorandum of understanding under this section—

(a) may include other provision about the ISC or its functions which is not of the kind envisaged in subsection (2) or (4),

(b) must be agreed between the Prime Minister and the ISC, and

(c) may be altered (or replaced with another memorandum) with the agreement of the Prime Minister and the ISC.

(6) The ISC must publish a memorandum of understanding under this section and lay a copy of it before Parliament.