There are normally between one and four assistant chief constables in British police forces, depending upon force size and whether or not civilians have been appointed at 'chief officer' level.
Assistant Chief Constables usually hold portfolios e.g. for crime, operations or territorial policing. In larger forces, ACCs may be given responsibilities for policing major territories within the force area.
Although the middle-ranking officers of the British police force are very well paid compared to comparable professions, chief officers are not paid as much as leaders of industry. In most cases, chief constables are paid less than Vice Chancellors of universities, with many fewer employees. However, the fact that officers of all ranks can (under current regulations) retire after thirty years on half-pay is an attractive feature of such posts.
ChiefConstable - is responsible for the direction and control of the Force, managing the budget and use of all funds and delivering objectives and targets within the Policing Plan.
AssistantChiefConstable Territorial Policing - is responsible for co-ordinating the management and provision of policing on the 12 territorial divisions, Force wide specialist uniformed and air support units, road policing, area operations rooms, and operational, public order and contingency planning.
AssistantChiefConstable Criminal Justice and Diversity Command - is responsible for co-ordinating the management and provision Force-wide of criminal judicial issues and delivering the Government agenda on 'Narrowing the Justice Gap'.
The office of Constable has existed since Saxon times, but a modern-type police force did not start until the early 19th century, with the introduction of a nationwide system of broadly similar local forces.
It was depersonalised, bureaucratic and hierarchical, with the new police constables instructed to prevent crime and pursue offenders.
However in contrast to the military gendarmerie forces of continental Europe, the British police, partly to counter public fears and objections concerning armed enforcers, were clearly civilian and their armament was initially limited to the truncheon.