Stephen Wheeler Downey (July 25, 1839 – August 3, 1902) was a lawyer and politician in Wyoming.Born in Westernport, Maryland, in 1861, Downey enlisted as a private in the 3rd Maryland Infantry, Potomac Home Brigade, and successfully promoted to first lieutenant, lieutenant colonel, and colonel. He was discharged after the Battle of Harpers Ferry due to wounds he sustained in the fighting. He studied law and was admitted to the bar in Washington, D.C.