James Brown Miller (October 25, 1861 – April 19, 1909), also known as "Killin' Jim", "Killer Miller" and "Deacon Jim", was an American outlaw and professional killer of the American Old West, said to have killed 12 people during gunfights – perhaps the most known homicides by one man of his era.
Miller was referred to by the alias "Deacon Jim" by some because he regularly attended the Methodist Church, and he did not smoke or drink.
He was lynched in Ada, Oklahoma, in 1909 along with three other men, by a mob of residents angry that he had assassinated a former deputy U.S.
marshal.
Miller was married to a daughter of a cousin of John Wesley Hardin, another notable Old West outlaw.