The fact that a small number of people could be identified as the only ones capable of having committed the offence could, in principle, afford reasonable grounds for suspecting each of them of the offence. The reasonableness of a police officer's decision to arrest had to be considered bearing in mind the effect on the suspects' right to liberty under Art.5 European Convention on Human Rights.The claimants (C) appealed from the decision of HH Judge Hewitt on 27 January 2003 dismissing their claims for damages. C had all worked for a local authority, monitoring recordings made by a town's closed circuit television (CCTV). A police officer from Northumbria Police had gone to the local authority to obtain CCTV tapes showing a young man that had been arrested trying the doors of cars. The relevant tapes appeared to the police to have been deliberately tampered with. The local authority investigated, but did not interview the staff individually, as it had intended to, and did not discover what had happened. The police carried out an investigation. Rather than seeking to interview C voluntarily, in June 1999 the police arrested each of them separately, pursuant to s.24(6) Police and Criminal Evidence Act 1984, on suspicion of committing an arrestable offence, namely perverting the course of justice. They were taken to the police station, questioned and released. In fact C were all innocent. They subsequently sought damages for the psychiatric consequences of their alleged wrongful arrest and false imprisonment. In dismissing their claims, the judge held that the police officers in question had acted in good faith, that they had had reasonable grounds for suspecting that each had perverted the course of justice and that the decision to arrest was a proper exercise of the officers' discretion. C submitted that (1) there were no facts that could properly have given rise to a reasonable suspicion that any of them had perverted the course of justice; (2) whether the decision to arrest was reasonable had to be answered in the context of the European Convention on Human Rights; (3) even if there were reasonable grounds for a suspicion, the judge was wrong to conclude that the decision to arrest was Wednesbury reasonable.HELD: (1) The judge had been entitled to accept that the police had taken all reasonable steps and had been left with the fact that one or more of those arrested had to have been the culprit. That situation could, in law, amount to "reasonable grounds" for the suspicion that the police undoubtedly had. The judge had therefore been entitled to find that there were reasonable grounds for suspecting that all of those arrested had committed the offence. In principle, nothing prevented opportunity from amounting to reasonable grounds for suspicion. There was no reason why, where a small number of people could be identified as the only ones capable of having committed the offence, that could not afford reasonable grounds for suspecting each of them, in the absence of any information that could or should enable the police to reduce the number further. (Hussein v Ching Fook Kam [1970] AC 942 considered; Castorina v Chief Constable of Surrey (1996) LG Rev Rep 241 considered) (2) The right to liberty under Art.5 of the European Convention on Human Rights had been engaged and any decision to arrest had to take into account the importance of that right, although the Human Rights Act 1998 had not been in force at the time. The court had to consider whether or not the decision to arrest was one which no police officer, applying his mind to the matter, could reasonably have taken, bearing in mind the effect on C's right to liberty. (3) Having found that the police had been entitled to doubt the genuineness of one of the tapes, the judge had also been entitled to conclude that the police could reasonably have decided to make the arrests because there appeared to have been a serious breach of the security of the CCTV monitoring system. The judge had also been entitled to conclude that C had not satisfied him that the decision to arrest was outside the boundaries of the discretion that the police had to exercise. The judge's decision had not been wrong although he had not approached the matter having regard to Art.5 of the Convention. The judge had obviously been keenly aware of the fact that C's right to liberty had been infringed and had considered the case in that light.Appeal dismissed.

[2003] EWCA Civ 1844