Conway v Rimmer

A ministerial certificate claiming Crown privilege is not conclusive. The court must determine whether relevant evidence should be withheld by balancing the public interest in protecting the state or public service against the public interest in the proper administration of justice.

The minister’s assessment carries great weight. It will ordinarily prevail where the reasons concern matters beyond judicial competence, such as national security. A class claim succeeds only where secrecy is necessary for the proper functioning of the public service. Routine reports receive no automatic protection merely because possible disclosure might affect candour. The court may seek fuller reasons, inspect documents privately and order production of any material whose disclosure would not cause sufficient public harm.

Conway v Rimmer concerned an action for malicious prosecution brought by a former probationary police constable against a police superintendent. The claimant had been acquitted of stealing a torch and was later dismissed from the police. He alleged that five undisclosed police documents could prove malice and want of reasonable and probable cause.

The documents comprised four probationary or training reports and a report prepared for possible submission to the Director of Public Prosecutions. The Home Secretary certified that the documents belonged to protected classes and that their production would injure the public interest. Both parties nevertheless wished them to be produced.

The majority of the Court of Appeal treated Duncan v Cammell Laird [1942] AC 624 as making the ministerial objection conclusive. The central issue before the House was whether the final decision on production rested with the executive or the courts and, if with the courts, how that power should be exercised.

1. Appeal allowed unanimously. All five Law Lords concluded that the final decision whether relevant evidence should be withheld rests with the court. The five documents were to be produced initially for private judicial inspection, after which the House would determine whether some or all should be disclosed.

2. Per Lord Reid, in reasoning expressly adopted by Lord Pearce and reflected throughout the other speeches, two public interests must be balanced: protection of the nation and public service from injury, and the proper administration of justice. A ministerial certificate is entitled to full weight but is not conclusive. Where the minister’s reasons concern matters which judicial experience cannot competently assess, the minister’s view must prevail. Lord Morris similarly emphasised that the independent court must ultimately hold the scales.

3. To the extent that Duncan v Cammell Laird [1942] AC 624 made a properly issued ministerial objection conclusive and denied the court power to inspect the documents, it was overruled. Its actual result concerning sensitive wartime submarine material remained correct, as did its fundamental rule that relevant documents must be withheld where the public interest requires. Lord Morris expressly considered it right to depart from its rule of conclusiveness. Lord Upjohn additionally considered its remarks about class claims strictly obiter because the actual claim concerned the documents’ contents.

4. The court may require clarification or amplification of the minister’s reasons and may inspect the documents privately. Inspection should be used cautiously but is legitimate because the privilege issue is distinct from the merits of the litigation. The court may restrict production to innocuous parts where that can be done without creating a distorted impression. The minister should have an opportunity to appeal before disclosure occurs.

5. Class protection remains available for material such as Cabinet papers, high-level policy communications, diplomatic despatches and security documents. Per Lord Reid and Lord Upjohn, however, a general concern that possible disclosure will inhibit candour does not automatically protect routine departmental communications. The relevant inquiry is whether secrecy for that class is genuinely necessary for the proper functioning of the public service.

6. Police documents can attract Crown privilege although police officers are not Crown servants. Information useful to criminals or relevant to a pending prosecution will ordinarily require protection. That consideration weakens after acquittal or a decision not to prosecute. The probationary reports were unlikely to cause harm if disclosed, while the prosecution report required inspection because of its possible importance and possible sensitivity.

7. Lord Hodson and Lord Pearce considered that section 28 of the Crown Proceedings Act 1947 preserved the applicable rule of law as it developed. It did not enact or crystallise the conclusive-certificate rule in Duncan v Cammell Laird.

• House of Lords: In Conway v Rimmer [1968] AC 910, the House unanimously allowed the appeal. It held that the court, rather than the executive, has the final responsibility for deciding a Crown claim to withhold evidence. The five documents were ordered to be produced for private judicial inspection.
• Court of Appeal: The majority treated Duncan v Cammell Laird [1942] AC 624 as binding and conclusive in favour of the ministerial objection. The citation of that decision is not stated in the judgment.