The Duke of Sussex v MGN Limited

Permission for collateral use of documents disclosed under compulsion depends on whether the interests of justice favour use outside the proceedings in which disclosure occurred. The discretion is broad but permission is exceptional. The applicant must show a good and cogent reason, and the court must consider whether the disclosing party would suffer unwarranted prejudice. The court balances the legitimate interests on both sides. Permission may be confined to particular documents, parties and proceedings, and may be accompanied by a further restriction on use.

The Duke of Sussex applied under rule 31.22(1) of the Civil Procedure Rules for permission to use documents disclosed by News Group Newspapers Limited in the mobile telephone voicemail interception litigation for his claim against MGN Limited in the Mirror Newspapers Hacking Litigation. He also sought permission to disclose the documents to other claimants.

The documents comprised invoices relating to private-investigator work and two emails concerning agencies or investigators. The issues were whether the proposed use was collateral use, whether the Duke’s legal team had previously breached the implied restriction on use, and whether the interests of justice and any prejudice to NGN justified permission.

1. Application granted in part. Permission was given to the Duke and three co-claimants to use the first category of documents, namely invoices, in the MNHL trial. Permission was refused in substance for the second and third documents because their only likely use would be to establish unlawful activity by agencies, causing prejudice to NGN in the separate MTVIL claim.
2. Documents disclosed under compulsion are subject to an implied limitation on use. Rule 31.22 confers a discretion to permit collateral use. The governing inquiry is whether the interests of justice favour permission. The applicant must establish a good and cogent reason, permission is exceptional, and the court must be satisfied that the disclosing party will suffer no unwarranted prejudice. The court must balance the legitimate interests of both parties.
3. The prior-breach objection failed. The evidence showed that the Duke’s solicitors acted in both litigations and already knew of relevant documents from work undertaken in the MTVIL. Retrieving and assembling known documents for the application did not breach the restriction on use.
4. Prejudice was material for the second and third documents. Their evidential value depended on establishing unlawful activity involving NGN journalists, which could prejudge an issue in the MTVIL trial. The first category was different: the invoices were directly relevant to challenging Mr Worden’s evidence and did not necessarily establish unlawful activity by NGN.
5. The documents could be used only for the MNHL trial. They were not to be disclosed to all other MNHL claimants. The first category was released to the permitted claimants and disclosed to MGN, subject to a restriction under rule 31.22(2), with use otherwise prohibited except in the MTVIL trial.