What is "citizen's arrest"

n. 1 (context uncountable legal English) The right of a person who is not acting as a sworn law enforcement official to detain a suspected criminal until the police can be summoned. 2 (context countable legal English) An arrest made under this right.

A citizen's arrest is an arrest made by a person who is not acting as a sworn law-enforcement official. In common law jurisdictions, the practice dates back to medieval England and the English common law, in which sheriffs encouraged ordinary citizens to help apprehend law breakers.

Despite the practice's name, in most countries, the arresting person is usually designated as a person with arrest powers, who need not be a citizen of the country in which they are acting. For example, in the British jurisdiction of England and Wales, the power comes from section 24A(2) of the Police and Criminal Evidence Act 1984, called "any person arrest". This legislation states "any person" has these powers, and does not state that they need to be a British citizen.