The U.S. Supreme Court case South Carolina State Highway Department et al. v. Barnwell Brothers, Inc., et al., 1937 revolved around the issue of state regulations on interstate commerce and their constitutionality under the Commerce Clause of the Constitution. The Barnwell Brothers, a trucking company from North Carolina, challenged South Carolina's laws that limited width and weight of trucks using its highways as they believed it was an undue burden on interstate commerce. However, in a unanimous decision by Justice Benjamin N Cardozo for the court held that these restrictions were not unconstitutional because they served a legitimate public interest - safety on highways - and did not discriminate against out-of-state businesses since both in-state and out-of-state vehicles had to abide by them equally.

In the dissenting opinion for South Carolina State Highway Department v. Barnwell Brothers, Inc., Justice Stone argued that the majority's decision to uphold a state law restricting truck width and weight on highways was an infringement upon interstate commerce. He contended that such regulations should be determined by Congress rather than individual states, as they directly affect trade between states. Furthermore, he pointed out inconsistencies in how different states regulate vehicle size and weight which could potentially disrupt uniformity in national transportation policy. In his view, these discrepancies underscored the need for federal regulation of interstate commerce to ensure consistency across state lines.