The Special Constabulary is the part-time volunteer section of statutory police forces in the United Kingdom and some Crown dependencies. Its officers are known as special constables (all hold the office of constable no matter what their grade) or informally as specials.
Every United Kingdom territorial police force has a special constabulary except the Police Service of Northern Ireland, which has a Reserve constituted on different grounds. However, the Royal Ulster Constabulary (and the previous Royal Irish Constabulary) did have its own Ulster Special Constabulary from 1920 until 1970, when the Reserve was formed. The British Transport Police (a national "special police force") also has a special constabulary. In the Crown dependencies, the Isle of Man Constabulary and the States of Guernsey Police Service also have special constabularies, but the States of Jersey Police does not.
The strength of the special constabulary as of 31 March 2010 in England and Wales was 15,505 and 1,653 in Scotland. Special constables are not the same as police community support officers (PCSOs), who are employed by police forces to provide operational support to regular officers. Special constables usually work for a minimum of 16/25 hours per month (depending on the force – the national minimum is 16 hours), although many do considerably more. Special constables might receive some expenses and allowances from the police service, including a £1,100 "recognition award" in Scotland and some forces in England, but their work is otherwise voluntary and unpaid.