The U.S. Supreme Court case Kassel, Director of Transportation, et al. v. Consolidated Freightways Corporation of Delaware in 1980 revolved around an Iowa statute that prohibited the use of 65-foot double-trailer trucks within its borders while neighboring states allowed them. The court ruled in favor of Consolidated Freightways Corporation, a trucking company challenging the law on grounds that it violated the Commerce Clause by placing an undue burden on interstate commerce. The majority opinion held that safety concerns cited by Iowa were not compelling enough to justify this restriction and noted inconsistencies in their application as shorter but potentially more dangerous vehicles were permitted under state law.

In the dissenting opinion for Kassel v. Consolidated Freightways Corporation of Delaware, Justice Rehnquist disagreed with the majority's view that Iowa's law banning 65-foot double trailers was unconstitutional. He argued that it is not within the jurisdiction of federal courts to decide on matters related to state traffic regulations and safety standards unless there is clear evidence of discrimination against interstate commerce. According to him, states should have autonomy in setting their own highway safety rules without interference from federal courts as long as they do not discriminate or impose undue burdens on interstate commerce. He also pointed out inconsistencies in how similar cases were decided by different courts due to lack of a standard criterion for evaluating such laws under Commerce Clause jurisprudence.