Ministry of Defence Police jurisdiction

MDP officers are attested as constables in one of the three jurisdictions of the United Kingdom: England & Wales, Scotland and Northern Ireland, but can exercise their powers in matters relating to the Ministry of Defence Estate throughout the United Kingdom, and additionally in the circumstances described below. MDP officers' jurisdiction relates to subject rather than geographic area and is set out in section 2 of the Ministry of Defence Police Act 1987, which was amended by the Anti-terrorism, Crime and Security Act 2001. MDP officers are based throughout the UK and exercise their jurisdiction over matters connected with the Defence Estate; there is no requirement for them to be on Ministry of Defence land when doing so.

If requested by a constable of:

to assist him in the execution of his duties in relation to a particular incident, investigation or operation, an MDP constable can "take on" the powers of the requesting officer for the purposes of that incident, investigation or operation. If a constable from a territorial police force makes the request, then the powers of the MDP constable extend only to the requesting constable's police area. If a constable from the BTP or CNC makes the request, then the powers of the MDP officer are the same as those of the requesting constable.

If requested by the Chief Constable of one of the forces mentioned above, an MDP constable takes on all the powers and privileges of members of the requesting force. This power is used for planned operations, such as the 2005 G8 summit at Gleneagles. This power is also used for national emergencies, such as the aftermath of the 7 July 2005 London bombings. This operation saw the MDP's largest deployment of firearms officers on a non Ministry of Defence tasking, providing mutual assistance to the Metropolitan Police.

An MDP constable can spontaneously take on the same powers and privileges of a constable of a territorial police force:

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