Southern Pacific Co. v. Arizona 325 U.S. 761 (1945)
SOUTHERN PACIFIC CO. v. ARIZONA 325 U.S. 761 (1945)
Arizona prohibited operation of a railroad train more than fourteen passenger cars or seventy freight cars long. The Supreme Court, 7–2, held the law an unconstitutional burden on interstate commerce. Chief Justice harlan fiske stone, for the Court, emphasized the magnitude of that burden; the law forced the railroad to operate thirty percent more trains in the state, and to break up and re-make trains; its total yearly cost to both railroads operating in the state was a million dollars. Stone also noted that requiring more trains would produce more accidents; the state's safety argument was weak. This interest-balancing analysis was far more demanding than the " rational basis " standard of review Stone had employed in South Carolina State Highway Department v. Barnwell Bros., Inc. (1938), upholding limits on truck widths and weights. Southern Pacific set the standard for future challenges to state regulations of commerce in the transportation field.
Kenneth L. Karst