Prison security categories in the United Kingdom

Prisoner security categories in the United Kingdom are one of four classifications assigned to every adult prisoner for the purposes of assigning them to a prison. The categories are based upon the severity of the crime and the risk posed should the person escape.

There are three different prison services in the United Kingdom, and separate services for the three Crown Dependencies. Her Majesty's Prison Service manages prisons in England and Wales, and also serves as the National Offender Management Service for England and Wales. Prisons in Scotland are managed by the Scottish Prison Service and prisons in Northern Ireland are managed by the Northern Ireland Prison Service. The Isle of Man and the Channel Islands also have their own prison administrations.

Prisons in England and Wales are divided into several categories relating to the age, gender and security classification of the prisoners it holds.

Male adult prisoners (those aged 21 or over) are given a security categorisation soon after they enter prison. These categories are based on a combination of the type of crime committed, the length of sentence, the likelihood of escape, and the danger to the public if they were to escape. The four categories are:

(Attempted) Murder, Manslaughter, Wounding with intent, Rape, Indecent assault, Robbery or conspiracy to rob (with firearms), Firearms offences, Importing or supplying Class A controlled drugs, Possessing or supplying explosives, Offences connected with terrorism and Offences under the Official Secrets Act

Category A, B and C prisons are called closed prisons, whereas category D prisons are called open prisons.

Category A prisoners are further divided into Standard Risk, High Risk, and Exceptional Risk, based on their likelihood of escaping.

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