Skip to main content

Accessibility controls

Main content area

Disclosure Manual: Chapter 34 - Handling National Security Related Claims for Public Interest Immunity

Refreshed: 21 October 2021|Legal Guidance


This guidance is intended to assist in the handling of PII applications in cases that involve sensitive material held by one of the intelligence and security agencies (the Security Service, the Secret Intelligence Service and GCHQ).

Prosecutors will be familiar with Part 1 of the Investigatory Powers Act 2016 (IPA), section 56 of which provides an exception to the disclosure regime under the common law and the CPIA. In dealing with this material, prosecutors should refer to their own internal guidance. The Attorney General's Section 18 RIPA Guidelines continue to be informative on this point.

In cases that involve agency material, the prosecutor with conduct of the case has the responsibility for instructing the prosecuting advocate. This guidance sets out agreed procedures for the revelation of agency material to the prosecutor, the procedure that the agency will adopt to obtain a ministerial certificate and emphasises the importance of making early contact.

Ministerial certificates

A ministerial certificate is the preferred means by which the agencies seek to claim PII before a court where there is agency material which:

  • is relevant to the case;
  • satisfies the disclosure test;
  • if disclosed, would cause a real risk of serious prejudice to an important public interest and;
  • the relevant agency's minister believes properly ought to be withheld.

If the case proceeds, the prosecution advocate will put the certificate before the trial judge in the same way as other prosecution material which is disclosable, sensitive and in respect of which a PII application ought properly to be made (see Chapter 13). Thus, where a PII claim may need to be made for agency material, the necessary preparatory work should, wherever possible, be carried out to an agreed timetable which accommodates the needs of the prosecutor, the agency, and any interested departments.

Liaison with the agency legal adviser

As soon as it appears to the officer in charge of investigation or the prosecutor that agency material may need to be considered for disclosure in the proceedings, arrangements for the viewing and handling should be done in accordance with Chapter 33.

If a PII claim may have to be made for agency material, the prosecutor should liaise with the agency legal adviser (and any other relevant department), to agree a timetable for the certificate process (with estimated/provisional timings) covering:

  • the anticipated date of the PII hearing (if possible). It is desirable to fix a date sufficiently far in advance of the trial for there to be time for the prosecutor to liaise appropriately about the future conduct of the proceedings should the judge order disclosure of material for which a claim is made, or indeed, in case of any other unexpected developments;
  • the latest date by which the signed PII Certificate should be obtained;
  • working back from this, and on the basis of guidance provided by the agency legal adviser, the latest realistic date by which the certificate and accompanying material should be submitted to the minister for consideration and signature; and
  • working back from this, and on the basis of any advice from the agency legal adviser, the latest realistic date by which the draft certificate and accompanying material should be submitted by the agency to the minster's department.

It is, of course, appreciated that time estimates are liable to change and that the timetable may have to be updated.

The agency legal advisor should also notify the Attorney General's Office (AGO) and the Government Legal Department's Litigation Division.

The prosecutor and the prosecution advocate, in liaison with the agency legal adviser, should ensure that all necessary information is provided in sufficient time to enable the agency to comply with its deadline for submitting the material and a draft certificate to the relevant minister's department. The prosecutor should ensure that the draft certificate sets out what material, in the opinion of the prosecutor, satisfies the disclosure test (and why), and whether, in the opinion of the agency, disclosure of the material would cause a real risk of serious prejudice to an important public interest.

Close liaison between the prosecutor and agency legal adviser is desirable to avoid delay. Generally, the prosecutor should supply the legal adviser with, as a minimum:

  • a case summary, and any communications from the defence or a copy of the CPIA defence statement if it has been received; and
  • advice from the prosecution advocate as to what agency material satisfies the disclosure test, thus identifying the material in relation to which PII needs to be considered.

The agency legal adviser will then take instructions from his or her respective agency as to whether disclosure of any of the identified material would cause a real risk of serious prejudice to an important public interest. The agencies will be anxious to avoid putting unnecessary claims before ministers or the courts.

If following this, if the agency considers that the identified material is both disclosable and sensitive, the legal adviser will liaise with the prosecutor and prosecution advocate to discuss whether the harm to the public interest in question can properly be avoided by the appropriate use of redactions, summaries or admissions. To assist this, the prosecutor should provide the legal adviser with an additional submission covering the information required by Chapter 13 of this manual. Where fairness can be maintained without damaging the public interest by providing a summary rather than the material in its entirety, the prosecutor should provide a suggested draft of that summary.

Where the agency wishes to redact certain passages, or withhold entire documents, because of their sensitivity, he or she will ask the prosecutor or prosecution advocate to advise on the impact of this on the fairness of the proceedings.

Special considerations apply to material obtained as a result of interception of communications pursuant to a warrant issued under Part 3 of RIPA. Section 56 of IPA largely excludes material obtained in this way from being adduced in any legal proceedings and material covered by section 56 should not be included in a PII claim. The interaction between Part 1 IPA and PII can, however, cause problems and this guidance should be read carefully, and be informed by the previous approach outlined in the Attorney General's Section 18 RIPA Guidelines.

Procedure for obtaining a ministerial certificate

If the agency legal adviser considers that a minister should be invited to sign a certificate in support of a claim for PII in proceedings before the court, they will submit the material, together with a draft certificate and the submissions or advice from the prosecutor and prosecution advocate, to the minister's departmental legal adviser. (He or she will also a copy to the AGO for information). When doing so, the agency legal adviser should ensure that the material is presented in a logical format, bearing in mind that the departmental legal adviser may not be familiar with either the background to the case or the techniques or other issues for which PII is being sought. For example, it may be helpful to group documents by individual topic rather than by date order. It is normally helpful if, whatever approach is used, this is reflected in a sensitive schedule accompanying the PII application, so that the legal adviser and subsequently the minister may use this as a framework for working through the papers.

Where there is a large amount of material and/or where it is unlikely that the minister can personally view all the material, the minister can properly be invited to consider a representative sample of the material with appropriate safeguards. Responsibility for making the selection rests with the department concerned, if necessary, in consultation with the agency legal adviser and possibly the prosecutor. A record of the material selected should be maintained.

The departmental legal adviser should advise the minister whether a PII claim for the material in question is justified, and therefore, must be satisfied that the certificate is cast in appropriate terms. To do this, the departmental legal adviser will generally need to view all the PII material, as well as read the advice and any other material prepared by prosecutor or prosecution advocate.

Where there is a particularly large amount of material and a representative sample is prepared for the minister, it will still generally be appropriate for the department legal adviser, as well as the agency legal adviser, to view all the material. This would appear to be in line with the general expectations of ministers, although it is accepted that, in the final analysis, it is up to individual departments to decide whether to follow this practice or whether, in a particular case (and bearing in mind the desirability of avoiding unnecessary duplication), they would wish to depart from it.

After the certificate and accompanying advice to ministers on the PII claim are finalised, the departmental legal adviser should consult the AGO, so that the certificate and submissions can (where appropriate) be cleared with the Law Officers (copies of the sensitive material itself should not normally be provided). In cases of particular difficulty or sensitivity, or where a novel point arises, the departmental or agency legal adviser may decide to seek advice and guidance from the AGO (and GLD) at an earlier stage.

The PII application

The guidance below should only be referred to in conjunction with that set out at Chapter 13.

When a minister has signed a certificate, it is normally appropriate for the prosecution advocate to make the submissions at the PII application, because the issue is usually where the balance of the public interest lies, and the advocate is in the best position to assist. To do this, the advocate should be provided with a copy of the certificate, the accompanying sensitive schedule and the agency material concerned. These must be returned to the agency after the hearing.

On rare occasions, a real question of principle may be raised as to the basis on which a particular claim is made, and or whether PII arises at all. In such cases the agency may instruct a separate advocate. Close liaison between the prosecuting case lawyer and the agency should ensure that the agency is aware of developments and should be able to take any necessary action immediately.

Once it becomes clear that a PII application will be required, the prosecutor should write to the court asking for a hearing to be fixed. The letter should follow the requirements and guidance set out at Chapter 13.

There should be early and close communication between the prosecutor, the agency legal adviser and the court manager to ensure that satisfactory practical arrangements are in place for the hearing.

Scroll to top