Reserve Forces Act 1980

3(1)Where in the United Kingdom or any colony a person surrenders himself to a constable as being illegally absent from the reserve forces, the constable shall (unless he surrenders himself at a police station) bring him to a police station.

(2)The officer of police in charge of a police station at which a person has surrendered himself as aforesaid, or to which a person who has so surrendered himself is brought, shall forthwith inquire into the case and if it appears to that officer that the said person is illegally absent as aforesaid he may cause him to be delivered into military or air-force custody, as the case may be, without bringing him before a magistrates' court or may bring him before such a court.