In the case of Chicago, Burlington and Quincy Railway Company v. Gray, the Supreme Court of the United States was asked to decide whether a state law that prohibited the sale of railroad tickets at a discount was constitutional. The plaintiff, the Chicago, Burlington and Quincy Railway Company, argued that the law violated the Commerce Clause of the United States Constitution, which gives Congress the power to regulate interstate commerce. The Supreme Court held that the law was constitutional. The Court reasoned that the law was a valid exercise of the state's police power, which allows states to pass laws to protect the health, safety, and welfare of its citizens. The Court also held that the law did not violate the Commerce Clause because it did not discriminate against interstate commerce. The Court's decision in this case established the principle that states may pass laws to protect the health, safety, and welfare of its citizens, even if those laws have an incidental effect on interstate commerce. This principle has been applied in numerous cases since then, and it remains an important part of the law today.

Justice Field delivered the dissenting opinion in Chicago, Burlington and Quincy Railway Company v. Gray. He argued that the majority's decision was contrary to both precedent and reason. The Court had held that a railroad company could not be liable for injuries sustained by an employee who was injured while working on a train owned by another company but leased to the plaintiff for use in its business operations. Justice Field disagreed with this conclusion, noting that it would lead to absurd results if applied more broadly; he believed it should only apply when there is no contractual relationship between two companies or where one of them has expressly assumed responsibility for any injury suffered by employees of the other party during their work on behalf of either company. Furthermore, he noted that such a rule would create uncertainty as to which party is responsible for providing compensation in cases involving multiple employers or contractors working together on projects related to transportation services provided by railroads.