O'Hara v. Chief Constable of the Royal Ulster Constabulary

The court considered the lawfulness of an arrest under section 12(1)(b) of the Prevention of Terrorism (Temporary Provisions) Act 1984. It confirmed that the statutory test requires the arresting constable to have a genuine suspicion and that there must be reasonable grounds for that suspicion. Those reasonable grounds must be matters which were in the mind of the arresting officer at the time of the arrest and are to be assessed by an objective observer applying the information actually in the officer's mind.

The House held that an instruction by a superior officer to arrest, without more, is not in itself sufficient to constitute reasonable grounds; however, information communicated at a briefing may supply reasonable grounds if the arresting officer genuinely possessed and relied on that information. On the facts the trial judge was entitled to infer that the briefing provided reasonable grounds and the Court of Appeal and House of Lords dismissed the appeal.

The appellant was arrested at his home on 28 December 1985 and detained under section 12(1)(b) of the Prevention of Terrorism (Temporary Provisions) Act 1984 in connection with a murder treated as an act of terrorism. The arresting constable said his suspicion derived from a briefing by a superior officer; the briefing officer did not give evidence and the details of the briefing were not explored in cross-examination. The appellant sued for wrongful arrest and other torts. At trial the judge accepted the arresting officer's evidence and, despite describing the disclosed material as "scanty", found the arrest lawful. The Court of Appeal upheld that decision and leave to appeal to the House of Lords was given.

The main legal issue was whether, under a provision requiring that a constable "has reasonable grounds for suspecting" (section 12(1)(b) of the 1984 Act), the reasonable grounds must exist objectively in fact or whether it is sufficient that they existed in the arresting officer's mind (for example because he had been told them by a superior). The House examined earlier authorities including McKee v. Chief Constable for Northern Ireland, Mohammed-Holgate v. Duke, Dallison v. Caffery and relevant Strasbourg authority. It held that the statutory test has both subjective and objective elements: the arresting officer must genuinely suspect and there must be reasonable grounds for his suspicion, but the objective assessment is directed to the information which was actually in the arresting officer's mind at the time. The court rejected the submission that a mere order to arrest by a superior officer, without further information having been provided to the arresting officer, would suffice to create reasonable grounds. Applying these principles to the facts, the trial judge was entitled to infer that the briefing furnished reasonable grounds and the appeal was dismissed.

The court also discussed the balance between individual liberty and the public interest in detecting crime and emphasised that the statutory test supplies the safeguard against arbitrary arrest.

Appeal dismissed. The House held that under section 12(1)(b) the arresting constable must personally have formed a genuine suspicion and that there must be reasonable grounds for that suspicion; those reasonable grounds are to be judged objectively by reference to the information in the arresting officer's mind at the time. A mere order to arrest by a superior officer is insufficient without further information being given, but on the facts the trial judge was entitled to infer that the briefing supplied reasonable grounds for suspicion.

First instance: trial before McCollum J., judgment 14 September 1990, which dismissed the appellant's claims except for confiscation of documents (for which the appellant was awarded return and £100). Court of Appeal (Kelly L.J., Pringle and Higgins JJ.) dismissed the appeal on 6 May 1994 (unreported). Leave to appeal to the House of Lords was granted; House of Lords decision delivered 12 December 1996 ([1996] UKHL 6).