Rule 303 made famous by Harry "Breaker" Morant and
Englishman living in Australia at the start of the 20th century who enlisted in the
Australian Armed Forces to help the British fight a war with the Boer's in South Africa. British policy to deal with the Boer "commando's" was to tell their men that any Boer found wearing khaki (the British uniform had changed by this time no more Red Coats) could be shot on sight to deter the Boer's from
pretending to be
British soldiers.Morant and his company while out to avenge the death of a close friend of his by Boer commando's came across a group who they believed had killed Morants friend, some of whom were dressed in the remants of British uniform (just a jacktet top) Morant set up a fireing squad and had the men shot dead with out any hearing.
After the peace was declared Morant and two others were brought before a British Military court charged with murder. The Head of the Brisih Army in South Africa sent his aid to the trial and had him commit purjury by denying any order to Kill Boer prisoners had been given. Atone point Morant was asked by the court under what rule or right did he kill the men and he answered that he shot them under rule 303 meaning the the Lee Enfield .303 rifle issued at the time. His meaning being that he shot them beacuse he had the means to do so at hand and that was all the authority he needed.