The legal right to search people or property. Private people have no powers of search, but various statutes, notably the Police and Criminal Evidence Act 1984, confer such powers on police or other officials, often on the authority of a search warrant issued by a magistrate or a High Court judge. The 1984 Act empowers the police to stop and search any person or vehicle found in a public place for stolen or prohibited articles and to detain a person or vehicle for such a search. (An article is “prohibited” if it is either an offensive weapon or made or adapted for use in connection with burglary, theft, taking a conveyance, or obtaining property by deception or fraud.) Before such a search the police officer must state his station and object. If out of uniform, he must produce evidence of his status. He must always give his grounds for the search if asked and must record details of it. A magistrate may issue a search warrant to an officer if he is satisfied that there are reasonable grounds for believing that a serious indictable offence has been committed and material evidence is to be found on the premises. Under the Theft Act 1968, for example, police may obtain a warrant to search for stolen goods when there are reasonable grounds for believing that they are in someone's possession or on his premises. Under certain circumstances the police are given powers of search without requiring either a warrant or any superior authorization; for example, under section 23 of the Misuse of Drugs Act 1971 (see controlled drugs) and sections 44–45 of the Terrorism Act 2000 (R (Gillan) v Metropolitan Police Commissioner  UKHL 12,  2 AC 307: see terrorism). The police also have a general power, when arresting someone for an indictable offence, to enter and search any place in which the suspect is believed to be. Statutes sometimes give powers of search to public officials, e.g. customs officers, Department of Trade and Industry officials, or Revenue officers.
Police powers of stop and search were extended under the Criminal Justice and Public Order Act 1994. Where a senior police officer reasonably believes that an incident involving serious violence may take place in his area he may issue an authorization (valid for 24 hours, extendable for up to 24 hours) for persons and vehicles (which can include caravans, ships, aircraft, and hovercraft and their passengers) to be stopped and searched if he thinks it expedient to do so to prevent violence. A constable in uniform may stop and search any person for the purpose of seeing whether that person is carrying an offensive weapon or an instrument that has a blade or a sharp point. Failure to stop is a summary offence punishable by one month's imprisonment and/or a fine on level 3. Failure to cooperate might amount to obstructing a police officer in the execution of his duty. Similar powers are available to senior police officers to authorize searches for periods of 28 days to prevent acts of terrorism. Both failure to stop and wilful obstruction of a constable are summary offences for the purpose of this power and are punishable by six months' imprisonment and/or a fine on level 5.