Public Interest Immunity

What is Public Interest Immunity? 

During the course of an investigation, the police may come into possession of sensitive material. This material may potentially be reasonably considered capable of undermining the case for the prosecution against the accused and/or of assisting the case for the accused. Nonetheless it may be withheld by the Crown under the “public interest immunity” (“PII”) principles.

An application for PII made by the prosecution must be heard and decided upon by the court. if the court orders that the prosecution do not have to disclose material to the defence, the defence may challenge that decision and the court may then either uphold its original ruling or order disclosure pursuant to the defence application. Issues relating to PII arise in both the magistrates’ court and the Crown Court.

The statutory provisions and codes in this area are as follows:

  • Criminal Procedure and Investigations Act 1996 (CPIA 1996);

  • The Criminal Procedure Rules 2005, Part 25;

  • Disclosure: Court of Appeal protocol for the control and management of unused material in the Crown Court.

  • Attorney-General’s Guidelines: Disclosure of Information in Criminal Proceedings.

Non-Disclosure on Public Policy Grounds

A conflict exists between the general principle that the administration of justice requires that the defendant should have full access to all non-privileged, relevant material and the doctrine that provides that certain material may be withheld if it is not in the public interest to disclose it.

Material may only be withheld on the basis that a successful claim of PII has been made by the party seeking to prevent disclosure.

The test for disclosure where public interest immunity is claimed 

The CPIA  1996 s.21(1) abolished the old common law rules in relation to the prosecution duty of disclosure and put in its place a new statutory framework. S. 3(6) (in relation to initial disclosure) and s.7A(8) (in relation to the prosecutor’s continuing duty) state that “material must not be disclosed…to the extent that the court, on an application by the prosecutor, concludes it is not in the public interest to disclose it and orders accordingly.”           

The main categories of sensitive material:

  • National security/Affairs and interests of state

  • Journalists’ sources

  • The prevention, detection & investigation of crime

  • Material relating to children or young children

These are just the most commonly occurring examples and thus this list should not be regarded as exhaustive. It is also important to remember that each case turns on its own facts and even cases involving the same type of documents may result in different disclosure decisions.

National security/Affairs and interests of state

A claim may be justified on the grounds that disclosure of material be prejudicial to national security. The test is whether disclosure would cause real harm to the public interest. Where the government minister is advised that disclosure of the document would cause real harm or a threat to national security, s/he is obliged to sign a PII certificate to that effect. Once the risk to national security has been certified by an appropriate ministerial certificate, the court should not exercise its right to inspect as the certificate will be conclusive.

Journalists’ sources

In summary, s.10 of the Contempt of Court Act 1981 provides that a court may not require a person to disclose any source of information contained in a publication unless the court is satisfied that it is in the interests of justice or national security or for the prevention of disorder or crime to order disclosure. In the absence of one of these criteria, a person cannot be held in contempt of court for refusing to disclose. 

The prevention, detection and investigation of crime

In criminal cases, the following categories are the ones that will be encountered most often:

  • Informers

It is established law that there is a clear public interest in protecting the identity of those who give information to the police. A ruling on this basis prevents the disclosure of any material that might lead to the identity of an informer being revealed.

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For more information on:

  • Police observation posts
  • Police reports, manuals and methods
  • Information relating to children
  • Procedural considerations
  • Scheduling of sensitive unused material
  • Duties of the prosecutor
  • The procedural guidelines
  • The prosecution application
  • The procedure for making a defence application for disclosure under the CPIA 1996
  • Performing the “balancing exercise”
  • What happens if disclosure is ordered?