Moseley held camp and Washington assignments from 1920–1929. He was a member of several important commissions, including the Harbord Commission to investigate Armenian issues. After commanding the Second Field Artillery Brigade, in 1921 he was detailed as assistant to General Dawes in organizing the newly created Bureau of the Budget. In 1921 he was promoted brigadier general, Regular Army. Commanding the 1st Cavalry Division (1927–1929), he successfully interceded, under fire, with principals in a 1929 Mexican insurrection. His actions stopped stray gunfire from Juarez, Mexico, from endangering life and property in adjacent El Paso, Texas, and precluded further incidents. In 1931 he was promoted major general, Regular Army.