201.This section deals with authorisations for intrusive surveillance. Such authorisations may only be granted by the Secretary of State (see sections 41 and 42) and by senior authorising officers as defined in subsection (6). Sections 33(3) and (4) provide that a senior authorising officer may not grant an authorisation, except on an application by a member of his/her force, Service, Squad or organisation.
202.Again, intrusive surveillance authorisations cannot be granted unless specific criteria are satisfied, namely that, the Secretary of State or senior authorising officer believes that:
the authorisation is necessary on specific grounds; and
the authorised activity is proportionate to what is sought to be achieved by it.
203.An additional factor which must be taken into account when considering whether the requirements are satisfied, is whether the information which it is thought necessary to obtain by the authorised conduct could reasonably be obtained by other means.
204.The specific grounds in this case are that it is necessary:
in the interests of national security;
for the purpose of preventing or detecting serious crime; or
in the interests of the economic well-being of the United Kingdom.
205.Sections 33 to 40 only apply to intrusive surveillance authorisations for investigations carried out by the police, NCIS, the National Crime Squad and Customs & Excise. They outline very similar procedures to those set out in part III of the Police Act 1997 (interference with property and wireless telegraphy).