In the case of Baltimore & Ohio Railroad Co. et al. v. United States et al., 1966, the U.S Supreme Court dealt with a dispute over freight rates for transporting iron ore. The Interstate Commerce Commission (ICC) had approved an increase in these rates proposed by several railroads, including Baltimore & Ohio Railroad Company and others against which major steel companies protested as discriminatory and unjustly high compared to other commodities' transportation costs. The District Court upheld ICC's decision but on appeal, the Supreme Court reversed this ruling stating that ICC failed to provide substantial evidence supporting its approval of increased rates or adequately explain why it considered them just and reasonable despite protests from shippers about their discriminatory nature towards certain regions or types of traffic.

In the dissenting opinion for Baltimore & Ohio Railroad Co. et al. v. United States et al., Justice Harlan disagreed with the majority's interpretation of Section 15(6) of the Interstate Commerce Act, arguing that it was not intended to allow railroads to establish through routes and joint rates without first obtaining approval from the Commission. He believed that this provision only allowed carriers to agree on divisions of joint rates already approved by or filed with the Commission, but did not grant them authority to create new through routes or joint rates independently. Furthermore, he argued that such an interpretation would undermine regulatory oversight over railroad pricing and routing decisions which could potentially lead to anti-competitive practices in violation of antitrust laws.