Chief constable is the title of the head of each United Kingdom territorial police force except the Metropolitan Police and City of London Police, which are headed by commissioners. Ranks above chief superintendent are usually non-operational management roles, and are often referred to as "chief officer" ranks, but the longer phrase "chief police officer" or similar in legislation is specifically a commissioner or chief constable, a "senior police officer" being their immediate deputy. The Commissioner of the Metropolitan Police is often considered to be the highest police rank within the United Kingdom, although in reality every chief constable and the two commissioners are supreme over their own forces and are not answerable to any other officer.