Detention under magistrates' warrants did not count for the purpose of s.38(1) Police and Criminal Evidence Act 1984, as fine proceedings were sui generis and an arrest for assaulting a police officer did not count for that section as it had not been a lawful arrest.Claimant's ('H') appeal from orders of HH Judge Dean QC on 21 November 2001 at Central London County Court after the trial before a judge and jury of H's claims against the Metropolitan Police for false imprisonment, negligence and assault. H, who had diabetes, was approached by two civilian warrant officers, one from Essex police with authority to execute two warrants for non payment of fines and convey H to prison, and a second officer, of the Metropolitan Police, who purported to arrest H in respect of the Essex Police warrants and took him to Shoreditch Police Station. H was late taking his medication, and on arrival at the police station was agitated and confused. It was alleged that H then assaulted a police officer. On hearing of H's diabetes, the custody sergeant summoned the police surgeon, who directed that H be taken to hospital. Officers from Essex Police were sent to the hospital, and subsequently left H there with officers of the Metropolitan Police, who conveyed H back to Shoreditch Police Station. On his return, H was arrested for the alleged common assault, which was in fact a non-arrestable offence such that the arrest was unlawful. H was bailed for that charge, but remained in detention on the basis that he was being detained in respect of the Essex warrants. H's condition worsened and a doctor recommended that H be taken to hospital. The custody sergeant determined that H should be handcuffed, and as a result of H's reaction to that decision, H was arrested for assaulting a police officer in the execution of his duty. H was subsequently charged and bail was refused on the basis that H was likely to abscond because of the outstanding Essex warrants. H was then taken by force to Old Street Magistrates' Court. H alleged that in the course of that journey he was assaulted. The justices ordered that H be taken to Pentonville as if he was serving for the Essex sentences. The judge ruled as follows: (i) s.38(1) Police and Criminal Evidence Act 1984 provided the justification for the detention of H notwithstanding the fact that the offence for which H had been arrested did not entitle arrest without warrant; and (ii) leaving his own questions to the jury, the judge decided that the matter of negligence should be left to the jury. The jury found as follows: (a) H had been falsely imprisoned for 22 minutes, for which ?22 was awarded; (b) one of H's eight claims of assault was proved, in respect of which £650 compensatory damages and £650 aggravated damages were awarded, with £5,000 exemplary damages; and (c) H's claims of negligence were rejected.HELD: (1) Section 38(1) contemplated a person being charged with an offence other than that for which he had been arrested, but required that the person be arrested "for an offence". There were only two possibilities, neither of which applied. First, detention under magistrates' warrants; however that did not count as the fine proceedings were sui generis such that H had not been arrested for an offence. Second, arrest for assaulting a police officer; but that did not count as it had not been a lawful arrest. Therefore the condition precedent for s.38(1) did not operate. There was no power to detain H for the purpose of conveying him to Old Street Magistrates' Court. The police had not proved that they were acting reasonably in relying on the Essex warrants. (2) The parties were entitled to one of two things: first, to a reasoned judgment from the judge on negligence, or, second, that specific facts be found by the jury and a reasoned judgment from the judge as to whether those facts amounted to negligence. Neither had happened in the present case.Appeal allowed. Retrial ordered.