Jonathan Alger v The Commissioner of Police of the Metropolis

For an arrest under Police and Criminal Evidence Act 1984, the officer must honestly believe that arrest is necessary for an identified statutory purpose, and that belief must rest on objectively reasonable grounds assessed against the information known at the time.

The court must examine the arresting officer’s actual reasons. It must not supply retrospective reasons which the officer did not consider. Necessity is a high threshold, not a synonym for convenience. The officer must give at least some consideration to practical alternatives, including voluntary attendance, with the depth of consideration depending on the circumstances. Where a suspect has voluntarily attended to assist, and poses no realistic immediate threat while at the police station, arrest may be objectively unsustainable.

The claimant appealed against the dismissal by HHJ Simpkiss in the County Court at Brighton of his claim for false imprisonment. The claim arose from his arrest at a police station after a customer alleged threatening conduct during a dispute about window-cleaning charges.

The arresting officer relied on the need for a prompt and effective investigation and the protection of the customer. The claimant had attended voluntarily, brought his phones to assist the investigation, and was willing to co-operate. The central issues were whether the trial judge had relied on reasons not considered by the officer and whether the officer had objectively reasonable grounds for believing arrest necessary under section 24(5) of Police and Criminal Evidence Act 1984.

1. Appeal allowed. The arrest and resulting detention were unlawful because the officer’s decision was not objectively supported by reasonable grounds.
2. Under section 24 of Police and Criminal Evidence Act 1984, the officer must honestly believe that arrest is necessary for an identified reason in section 24(5). The decision must also be objectively reasonable when reviewed against the information known to the officer at the time. Necessity sets a high bar and means more than desirability or convenience.
3. The court must focus on the arresting officer’s actual reasons, rather than reasons which might arise by inference or retrospective justification. The trial judge erred by relying on the possibility that a voluntary interview could be terminated and that the claimant might send associates to threaten the complainant. Neither possibility formed part of the officer’s reasoning, and the latter had no evidential foundation in this case.
4. An officer must give at least some consideration to whether voluntary attendance would achieve the intended objective. That consideration may be cursory in some cases, but requires more careful analysis where the suspect has already attended voluntarily, is waiting to assist, and the alleged conduct does not indicate a realistic immediate threat while the suspect remains at the station.
5. Interviewing the claimant did not itself require arrest. The later reference to seizure of his phones was not a genuine reason for arrest, and bail conditions were not part of the officer’s reasoning. The officer had not adequately considered voluntary interview or explained why arrest was necessary to protect the complainant. The decision was therefore objectively unsustainable.
6. Aggravated damages were refused. Although the arrest was unlawful, it was carried out calmly and professionally and involved no unusual aggravating features. Basic damages of £2,750 were awarded for approximately seven hours’ detention, with the parties directed to prepare a draft order.

• High Court (King's Bench Division) — The appeal from the County Court at Brighton was allowed. The dismissal of the false-imprisonment claim was set aside and damages of £2,750 were awarded.
• County Court at Brighton — HHJ Simpkiss dismissed the claimant’s claim.