Counter-Terrorism Act 2008
I don't know if Sections 19 to 21 of the Counter-Terrorism Act 2008 are of any relevance, but subsection 19 (6) gives another good example of New Labour's attitude towards privacy and confidentiality, though Section 20 refers to the Data Protection Act 1998 in what appears to be a more reassuring way. I don't know if these Sections have ever been commenced, or how the Data Protection act 1998 interacts with these Sections. (Might the Data Protection Act offer no protection at all?)
http://www.legislation.gov.uk/ukpga/2008/28/part/1/crossheading/disclosure-of-information-and-the-intelligence-services
Here's some of Sections 19 and 20:-
"19 Disclosure and the intelligence services
(1) A person may disclose information to any of the intelligence services for the purposes of the exercise by that service of any of its functions.
(2) Information obtained by any of the intelligence services in connection with the exercise of any of its functions may be used by that service in connection with the exercise of any of its other functions.
...
(6) A disclosure under this section does not breach—
(a) any obligation of confidence owed by the person making the disclosure, or
(b) any other restriction on the disclosure of information (however imposed).
(7) The provisions of this section are subject to section 20 (savings and other supplementary provisions).
20 Disclosure and the intelligence services: supplementary provisions
...
(2) Nothing in that section authorises a disclosure that—
(a) contravenes the Data Protection Act 1998 (c. 29), or
(b) is prohibited by Part 1 of the Regulation of Investigatory Powers Act 2000 (c. 23).
..."
So, in light of that, what does "Your personal information is protected by law. Census information is kept confidential for 100 years" really mean? Does it mean census staff can disclose everything we put on the forms to the Security Service (MI5), Secret Intelligence Service (MI6) and GCHQ?