A state in which a national police organization, often secret, is under the direct control of an authoritarian government, whose political purposes it serves, sometimes to the extent of becoming a state within a state. The inhabitants of a police state experience restrictions on their mobility, and on their freedom to express or communicate political or other views, which are subject to police monitoring or enforcement. In some cases, the exercise of police control is supported by systems, such as internal passports or internal exile, or by punishment camps. There is also often a strict system of censorship and extensive secrecy.