Andrew Osarinmwian, R (on the application of) v Manchester Crown Court

On an application to extend a custody time limit, the question whether the prosecution acted with all due diligence and expedition is fact-sensitive. Judicial review considers whether the judge’s conclusion on that statutory precondition was reasonable in public law terms. The review is supervisory, not a rehearing, and does not ordinarily proceed on fresh evidence. Genuine difficulties, good-faith mistakes and case complexity may be relevant. The standard is not perfection or hindsight. A detailed chronology and sufficiently comprehensive material should be placed before the judge. Where the judge has considered the chronology, evidence and submissions and the conclusion is reasonably open, the reviewing court should not substitute its own assessment.

The claimant sought judicial review of a Manchester Crown Court decision extending his custody time limit in an EncroChat prosecution. Disclosure of evidential material had been ordered under Criminal Procedure and Investigations Act 1996, s.8, but the material was not supplied in the required form and the trial was vacated.

After a hearing on 12 October 2023, the Crown Court extended the custody time limit from 13 October 2023 to 28 March 2024. The claimant argued that the prosecution had failed to act with all due diligence and expedition, and that the Crown Court judge’s contrary conclusion was unreasonable. The central issue was the proper scope of supervisory review of that conclusion.

1. Permission and outcome. Permission to apply for judicial review was granted, but the substantive claim was dismissed. The application for interim relief fell away.
2. The statutory precondition for extending a custody time limit was whether the prosecution had acted with all due diligence and expedition. The judicial review court’s task was to assess whether the Crown Court judge’s conclusion was reasonably open to him, applying supervisory scrutiny rather than conducting a rehearing or substituting its own view.
3. The assessment was fact-sensitive. There was no automatic rule that service of an application for disclosure under s.8 required the prosecution invariably to gather all potentially relevant material before the court decided the application. What due diligence required depended on the particular circumstances, including the nature of the material, the difficulties encountered and the steps taken to address them.
4. The prosecution had made significant errors concerning the temporal scope and format of disclosure, the expert’s email address and copying the defence team into communications. Those errors were accepted as good-faith mistakes. The evidence also showed genuine difficulties in obtaining material held by multiple sources, and repeated requests to the Crown Court for an urgent further hearing.
5. The Crown Court judge had before him a detailed chronology, defence annotations, written submissions and expert evidence. He correctly directed himself that perfection and hindsight were not the applicable standards. It was reasonably open to him to conclude that, viewed in the circumstances as a whole, the prosecution had not failed to act with all due diligence and expedition. The claim therefore failed.
6. Had the claim succeeded, consideration of bail conditions would have been left to the Crown Court.

This was a first-instance judicial review. The challenged decision was made by Manchester Crown Court, which extended the claimant’s custody time limit from 13 October 2023 to 28 March 2024. The High Court granted permission but dismissed the substantive claim.