s 63 Additional restrictions on grant of authorisations under section 61
(1) A designated senior officer may not grant an authorisation under section 61 for the purposes of a specific investigation or a specific operation if the officer is working on that investigation or operation. (2) But, if the designated senior officer considers that there are exceptional circumstances which mean that subsection (1) should not apply in a particular case, that subsection does not apply in that case. (3) Examples of exceptional circumstances include— (a) an imminent threat to life or another emergency, (b) the investigation or operation concerned is one where there is an exceptional need, in the interests of national security, to keep knowledge of it to a minimum, or (c) there is an opportunity to obtain information where— (i) the opportunity is rare, (ii) the time to act is short, and (iii) the need to obtain the information is significant and in the interests of national security. (d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .