John Thomas Perceval (14 February 1803 – 28 February 1876) was a British army officer who was confined in lunatic asylums for three years and spent the rest of his life campaigning for reform of the lunacy laws and for better treatment of asylum inmates.[1] He was one of the founders of the Alleged Lunatics' Friend Society and acted as their honorary secretary for about twenty years. Perceval's two books about his experience in asylums were republished by anthropologist Gregory Bateson in 1962,[2] and in recent years he has been hailed as a pioneer of the mental health advocacy movement.[3][4]