Military policeman
From Tardis Wiki, the free Doctor Who reference
A British military policeman was abducted from World War I by the War Lords and hypnotised into believing he was still fighting in the War when he participated in the War Lords' War Games. He spotted Jamie McCrimmon and a redcoat after they had escaped and warned them to stop, or else he would fire at them. He then shot and injured the redcoat and had Jamie brought to Commandant Gorton.
He, like all the surviving victims of the War Lords, was returned home by the Time Lords. (TV: The War Games)