He married Alice Clymer Macfarlane in 1900, they had one child.
He was promoted to vice-president of the Louisville and Nashville Railroad in 1901. Hines spent nearly ten years fighting railroad regulation in state and federal courts.
In December, 1917, President Woodrow Wilson nationalized most U.S. railroads under the United States Railroad Administration. William G. McAdoo was made director general, Hines agreed to become assistant director general. McAdoo resigned in January, 1919, and Hines stepped in as director general for the remainder of nationalization under the Railroad Administration, which ended on March 1, 1920.[2] Following the end of World War I, Hines worked and traveled extensively in Europe.
William R. Doezema, "Walter D. Hines," in Railroads in the Age of Regulation, 1900-1980, ed. Keith L. Bryant Jr., a volume of the Encyclopedia of American Business History and Biography (1988), pp. 201–12.
Robert T. Swaine, The Cravath Firm and Its Predecessors, 1819-1947, vol. 2 (3 vols., 1946–1948).