Interception of Communications Act 1985
Report presented to parliament that deals with the Secretary of State's power to issue interception warrants at the request of the intelligence and security agencies.
http://www.archive.official-documents.co.uk/document/cm47/4778/4778.htm - Detail ...
Google PR

Security Service Act 1989
Report by the Security Service Commissioner, which examines the Secretary of State's powers to issue, renew, and cancel warrants. In addition, too investigating cases referred to the Commissioner by the Security Service Tribunal.
http://www.archive.official-documents.co.uk/document/cm47/4779/4779.htm - Detail ...
Google PR

Terrorism Act 2000
Act detailing the legal measures that are available in the prevention of terrorism.
http://www.opsi.gov.uk/acts/acts2000/ukpga_20000011_en_1 - Detail ...
Google PR

Regulation of Investigatory Powers Act 2000
Provides for the interception of user logs and e-mails of suspected criminals by the security and intelligence services.
http://www.opsi.gov.uk/acts/acts2000/ukpga_20000023_en_1 - Detail ...
Google PR