Sheriff Cranmer was shot and killed by a prisoner while checking on the man. The suspect was in the county jail for assault.

A brakeman on a Missouri Pacific freight ejected two tramps at Otterville at night, March 21, 1890. One or the tramps took a shot at the brakeman. The tramp, William E. West, was jailed in Sedalia for carrying a concealed weapon. A charge of felonious assault with a deadly weapon was filed in Cooper County. West received a light jail term. A fellow prisoner following his release returned to the jail and slipped a gun to West through the jail window. On June 15, 1890, Sheriff Cranmer, entering the cell-block. West confronted Sheriff Cranmer and shot him through the arm, the bullet then passed through the sheriff's kidney. The Sheriff fired on West but his two shots missed their target. Sheriff Cranmer reported the escape, and collapsed. West was captured by a posse and returned to the jail within the hour.

West was hanged for Sheriff Cranmer's murder on March 6, 1891.

Sheriff Cranmer was survived by his wife, Lucy, and his children, Mary and Thomas.
Interred: Otterville IOOF Cemetery, also known as Odd Fellows Cemetery