Greater Manchester Police v Andrews

Privilege against self-incrimination may arise when permission is sought to serve a disclosure notice under section 49 of the Regulation of Investigatory Powers Act 2000. Its engagement is limited where the notice requires disclosure of an encryption key, because the key itself is neutral and the encrypted material already exists independently of the suspect’s will. The court must assess proportionality, including the public interest in preventing or detecting crime. Permission may properly be granted where knowledge of the key could be incriminating, particularly because safeguards remain available at any subsequent trial.

The Chief Constable appealed by way of case stated against a Crown Court decision refusing permission to serve the respondent with a notice under section 49 of the Regulation of Investigatory Powers Act 2000. Encrypted data had been found on pen drives seized during an investigation into suspected child-image offences. The Crown Court considered that requiring disclosure of the encryption key might infringe privilege against self-incrimination because there was no independent evidence that the respondent knew the key.

The central issues were whether privilege could arise at the permission stage and, if so, whether requiring disclosure was proportionate.

1. The appeal was allowed. The matter was remitted to the Crown Court with a direction that written permission be given to serve the section 49 notice.
2. Privilege against self-incrimination may arise when an application for permission to serve a disclosure notice is made. It is not necessary to wait until the notice has been served and the recipient claims privilege. The court adopted the approach in R v S and Anr [2008] EWCA Crim 2177 and R v SF [2009] 1 WLR 1489.
3. The privilege was engaged only to a very limited extent. An encryption key, like the encrypted data, exists independently of the suspect’s will once created. The key is neutral, although knowledge of it may become incriminating.
4. The limited interference was proportionate under section 49(2)(c). The public interest in preventing or detecting crime supported disclosure, and it was a legitimate objective to make lawfully seized encrypted material intelligible. The judge had taken an unduly narrow view of the evidence when inferring that the respondent might know the relevant keys from the circumstances in which the pen drives were recovered.
5. Procedural safeguards remained available at any later trial. The trial judge could exclude evidence concerning the underlying material, the key or means of access, and the respondent’s knowledge of the key. Those safeguards supported the conclusion that permission should be granted.

• High Court (Administrative Court): Appeal by way of case stated allowed. The matter was remitted for written permission to be given under Schedule 2 of the Regulation of Investigatory Powers Act 2000.
• Crown Court: HHJ Steiger QC refused the application for permission on 18 November 2010. The stated case was dated 25 January 2011.