In the case of Louisville & Nashville Railroad Company v. Finn and Others as Railroad Commission of Kentucky, 1914, the Supreme Court was asked to determine whether a state railroad commission had the authority to set rates for intrastate commerce that were lower than those established by an interstate commerce commission. The Louisville & Nashville Railroad Company argued that this violated their rights under the Fourteenth Amendment because it resulted in unjust discrimination against interstate commerce. The court ruled in favor of the railroad company, finding that while states have broad powers over local matters such as intrastate railroads, they cannot use these powers in a way that interferes with or burdens interstate commerce. This decision affirmed federal supremacy over interstate trade regulation and reinforced protections against discriminatory practices affecting such trade.

In the dissenting opinion for Louisville & Nashville Railroad Company v. Finn and Others as Railroad Commission of Kentucky, Justice Holmes argued that the majority's decision was a departure from established principles of law regarding interstate commerce. He contended that it is not within the purview of state authorities to regulate rates for transportation services crossing state lines, even if part of those services are conducted within their jurisdiction. This power belongs exclusively to Congress under its constitutional authority over interstate commerce. The fact that some parts of an interstate journey occur solely within one state does not give that state regulatory control over rates charged for the entire trip; such regulation would interfere with uniformity in national commercial policy and could lead to conflicting requirements between states. Therefore, he believed this case should have been decided in favor of the railroad company rather than upholding Kentucky’s right to set intrastate railway rates.