Fundamental to an understanding of the legal position of British police is the role of the constable, which derives from common law. The powers that the law gives to police are vested in individual constables. In theory, constables and metropolitan and City of London police commissioners are said to have full operational independence from national and local government. The statutes defining and distributing police power are discussed, as are regulations governing police organization and the vicarious liabilities of chief officers. 43 footnotes.