5.5The current law on how national security information is dealt with in proceedings differs somewhat depending on what type of proceedings are involved.
5.6The current position is that national security information can be withheld by the Crown under the doctrine of public interest immunity and not disclosed to the other party in civil proceedings. Under section 27(3) of the Crown Proceedings Act 1950, if the Prime Minister determines that national security information is too prejudicial to disclose, he or she can issue a public interest immunity certificate. Section 27 certificates have only rarely been used. Traditionally, these certificates were treated as decisive. At the same time, there has always been the ability for the court to question the certificate, and perhaps to reject it, and some uncertainty around the level of judicial deference and the role of judges in viewing the underlying material before making their decision.
5.8Although it is obviously speculation, we consider that it very likely that the courts would take the same approach to public interest immunity here as has been taken in the United Kingdom and look at the underlying material before making their decision whether to uphold a claim of public interest immunity.
5.9Under section 70 of the Evidence Act 2006, information relating to matters of state may be excluded from proceedings “if the Judge considers that the public interest in the communication or information being disclosed in the proceeding is outweighed by the public interest in withholding the communication or information”. Section 70 of the Evidence Act takes a different approach than section 27(3) of the Crown Proceedings Act because it says that the judge does a balancing act and determines whether national security information must be disclosed to the other party and whether the information can be put before the decision-maker.
5.10It is not clear how this section and section 27(3) of the Crown Proceedings Act relate to each other. The fact that, under section 70 of the more recent Evidence Act, the judge determines whether national security information must be disclosed to the other party also supports our view that the level of deference displayed by the court in the Choudry decision is unlikely to be repeated should the issue be before the higher courts again.
5.11Section 52(4) of the Evidence Act allows judges to make directions to protect sensitive information, including national security information, but there is little case law under the section, and it does not explicitly provide for a closed procedure or use of special advocates. This is an essentially procedural provision, combined perhaps with the use of inherent jurisdiction, neither of which give much guidance as to how to balance the needs of natural security with natural justice and open justice. In contrast, under section 27, courts can only choose between upholding the certificate and denying disclosure of relevant material, or potentially requiring critical material to be disclosed, but at the cost of national security material being released. Our Report seeks to remove the stark choice under the Crown Proceedings Act and clarify the tools available to judges under the Evidence Act.
5.12The Criminal Disclosure Act 2008 applies to criminal proceedings. The Act codified the common law of public interest immunity for criminal proceedings. If relevant information cannot be disclosed by the prosecution to the defence because it would prejudice security interests, that information can be withheld, which also means that it will not be presented in evidence.
5.14Where national security information is relevant to an administrative decision in respect of a person’s rights, obligations or interests, it can be withheld by the Crown but still used to inform the decision. There are a number of statutory regimes in place (for example, the Immigration Act 2009, the Passports Act 1992 and the Terrorism Suppression Act 2002) that provide that national security information can be taken into account by decision-makers without disclosing that information to the affected person.
5.15Closed court procedures have been established by legislation to hear appeals and reviews in cases where national security information has formed part of the decision under review or needs to be introduced at appeal or review. There are inconsistencies in approach, and new regimes have been enacted in response to particular issues rather than in a coherent and principled way, the most recent example being that contained in Schedule 4 of the Health and Safety at Work Act 2015. There are questions over whether some of these regimes provide adequate safeguards for the affected person or give the courts sufficient control over proceedings.