There isn’t any argument that use of the expression in the U.S. refers to someone sneaking around silently in a sly or underhanded manner. The Online Etymology Dictionary attributes its origin as being “…the nickname of U.S. government Indian Affairs agent W.E. Johnson (1862-1945) who was noted for his stealthy tactics” in combating the use of alcohol. Word Origins adds that Johnson’s reputation followed him to England in 1916 where the expression became used to describe a teetotaler “…who advocates prohibition.”