Security of census data

You asked

1. Is the information in the following article correct: https://www.theregister.com/2011/03/25/confidentiality_of_census_data_not_guaranteed/?
2. Notwithstanding the article above, in any given scenario including terrorism and related legislation pertaining to police, government agencies (MI5/MI6 et al) and data collection, warrants. etc - can, has and will census data be used to 'catch terrorists' or be 'passed on' or 'collected' or 'shared' or 'distributed' with said agencies?

We said

Thank you for your request.

The Statistics and Registration Services Act 2007 (SRSA) makes it a criminal offence, subject to a maximum penalty of 24 months imprisonment and/or a fine, for a member or employee of the UK Statistics Authority (UKSA) (of which the Office for National Statistics (ONS) is the executive arm) to unlawfully disclose personal information held by the Authority in relation to any of its functions. As per government policy, personal census data remains in the custody and ownership of the UKSA for 100 years.

Although the Act allows disclosure of personal data in some circumstances, such as for the purposes of criminal investigations or proceedings, the key point to note is that the Act does not require this to happen. Therefore, whilst ONS has the powers to disclose data, it does not have an obligation to do so, and, indeed, maintains a strict policy of refusing requests to disclose such data. The UKSA's policy, and ONS practice, has been, and remains, that:

• The UKSA, the ONS and the National Statistician will never volunteer to disclose personal information for any non-statistical purpose;
• If disclosure is sought, such as through a court order, the UKSA and the National Statistician will always refuse to allow it, and will contest the case to the maximum extent possible under the law, using each stage of appeal in the Courts if necessary, in order to ensure statistical confidentiality; and will do so in an open, public and transparent manner, to the extent permitted under the law.

The UKSA has never passed information onto the security services.