Police forces in the United Kingdom

Law enforcement in the United Kingdom is organised separately in each of the legal systems of the United Kingdom: England and Wales, Northern Ireland and Scotland. Most law enforcement is carried out by police officers serving in regional police services within one of these jurisdictions. These regional services are complemented by UK-wide agencies, such as the National Crime Agency, and specialist bodies hosted by regional police forces, such as the Specialist Operations directorate of the Metropolitan Police.

Police officers are granted certain powers to enable them to execute their duties. Their primary duties are the protection of life and property, preservation of the peace, and prevention and detection of criminal offences. In the British model of policing, officers exercise their powers to police with the implicit consent of the public. "Policing by consent" is the phrase used to describe this. It expresses that the legitimacy of policing in the eyes of the public is based upon a general consensus of support that follows from transparency about their powers, their integrity in exercising those powers and their accountability for doing so.

In the United Kingdom, every person has limited powers of arrest if they see a crime being committed: at common law in Scotland, and in England and Wales if the crime is indictable – these are called "every person powers", commonly referred to as a "citizen's arrest". In England and Wales, the vast majority of attested constables enjoy full powers of arrest and search as granted by the Police and Criminal Evidence Act 1984. All police officers are "constables" in law, irrespective of rank. Although police officers have wide ranging powers, they are still subject to the same laws as members of the public. However, there are certain additional legal restrictions on police officers such as the illegality of taking industrial action and the ban on taking part in active politics.

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