Authorised firearms officer

Candidates are required to gain approval from their superiors before embarking on a series of interviews, psychological and physical fitness tests, medical examinations and assessment days, before permission to commence firearms training is given.

There is no guarantee of success; candidates can be returned to their previous role at any point in training if they do not meet the required standard.

The common role of an SFO is to assault premises involved in a siege situation, effect high-risk firearms related arrests and respond to terrorist threats.

[6][7][full citation needed] A counter terrorist specialist firearms officer (CTSFO) is the highest AFO level in the National Police Firearms Training Curriculum (NPFTC) and was established by the Metropolitan Police Service in the lead up to the 2012 Summer Olympics held in London on 27th of July.

[8][10][11][19] The national Combined Response Firearms Teams established for the Olympics was maintained after the closing of the Games forming the basis of the CTSFO Network.

[20][11] In 2013, West Midlands Police CTSFOs deployed to London to support the MPS following the Murder of Lee Rigby in Operation Pegboard.

[24] When working at airports, nuclear sites, on protection duties and deployed in armed response vehicles in certain areas, 'standing authority' is granted to carry personal sidearms.

[25] All members of the Police Service of Northern Ireland have authority to carry a personal issue handgun as a matter of routine, both on duty and off.

[26] United Kingdom law allows the use of "reasonable force" in order to make an arrest or prevent a crime[27][28] or to defend oneself.

[31] ACPO policy states that "use" of a firearm includes both pointing it at a person and discharging it (whether accidentally, negligently or on purpose).

[35][36] However this does not include the Police Service of Northern Ireland where all roughly 7,000 officers there are trained to AFO as standard and carry a Glock 17 sidearm as routine.