R v Chief Constable of the West Midlands Police, ex parte Wiley; R v Chief Constable of Nottinghamshire Police, ex parte Sunderland (consolidated appeals)

The House of Lords held that public interest immunity does not extend as a general class immunity to all documents generated by an investigation of a complaint against the police under Part IX of the Police and Criminal Evidence Act 1984. The court concluded that the earlier line of authority starting with Neilson v Laugharne and extended in subsequent cases was wrongly decided and should be overruled so far as it created a broad class rule preventing disclosure or use of all materials arising from police complaints investigations.

The correct approach is to assess claims to public interest immunity by reference to relevance and materiality and to weigh the public interest in preserving confidentiality against the public interest in the administration of justice; particular documents (or parts of documents) may attract protection on their contents where necessary, but a blanket class immunity is not justified. The court also held that collateral proceedings by way of judicial review to determine use of material in separate civil litigation are generally undesirable and that injunctions preventing any use of knowledge derived from documents are inappropriate save in exceptional circumstances.

This case concerned consolidated appeals from orders of Popplewell J and the Court of Appeal that had recognised a class-based public interest immunity attaching to files created under the police complaints code (Part IX of the Police and Criminal Evidence Act 1984), and had granted declarations and an injunction preventing use of such material in contemplated civil claims. The applicants (chief constables) appealed to the House of Lords; the respondents (Wiley and Sunderland) had sought undertakings that the police would not use complaints material in subsequent civil proceedings and in one case sought judicial review of a decision to dispense with investigation.

The principal issues were (i) whether documents generated in investigations under Part IX constitute a class of material immune from disclosure and use by virtue of public interest immunity, and (ii) whether collateral judicial review proceedings and injunctions restraining use of information derived from such documents were appropriate remedies.

• Nature of applications: judicial review applications by complainants seeking undertakings and injunctions restraining the police from using materials created in complaint investigations; related appeals by Chief Constables against declarations/injunctions granted below.
• Issues before the court: scope of public interest immunity (class claim v contents claim) in relation to police complaints files under Part IX PACE 1984; whether the courts should recognise an absolute class immunity preventing use as well as disclosure; appropriateness of collateral proceedings and injunctions to enforce such immunity.

The House reasoned that the line of authority beginning with Neilson v Laugharne, which had recognised a broad class immunity for police complaints files, rested on insufficient evidence and led to unfair and artificial consequences (including deterrence of complainants and distortion of litigation). The proper legal approach is to require relevance and materiality for disclosure and then to weigh competing public interests; class-based immunity for all complaint files was not shown to be necessary. The court allowed the appeal, set aside the lower courts' orders (save as to legal aid taxation) and remitted the cause to the Queen's Bench Division for further proceedings consistent with the judgment. The Lords observed that narrower class or contents protection might be justified for specific documents (for example, sensitive operational material or particular investigative reports) but such claims must be established on evidence in the appropriate proceedings. The court also warned against determining disclosure/use disputes in collateral proceedings and against blanket injunctions preventing use of information derived from documents except in exceptional circumstances.

Appeal allowed. The House held that the court below was wrong to maintain a general class-based public interest immunity attaching to all documents generated by Part IX police complaints investigations; Neilson v Laugharne and subsequent authorities extending a broad class immunity were wrongly decided. Public interest immunity must be assessed by reference to relevance and materiality and a weighing of competing public interests; particular documents may attract protection on their contents, but there is no automatic class immunity preventing disclosure or use. Collateral proceedings and broad injunctions preventing any use of knowledge derived from such documents are inappropriate in general. The orders of the Court of Appeal and of Popplewell J were set aside save as to legal aid taxation and the cause was remitted to the Queen's Bench Division for further proceedings consistent with this judgment.

First instance: judicial review applications heard by Popplewell J (orders dated 16 December 1992). Court of Appeal: orders of 23 July 1993 (appeal dismissed). Leave to appeal to the House of Lords was given; House of Lords allowed the appeals and set aside the lower courts' orders (save as to legal aid taxation) and remitted the cause to the Queen's Bench Division. [1994] UKHL 8.