United States v. New Orleans Railroad was a Supreme Court case that addressed the issue of whether the federal government had the power to regulate interstate commerce. The case arose when the New Orleans Railroad Company refused to comply with a federal law that required it to pay a fee for transporting goods across state lines. The railroad argued that the federal government did not have the authority to regulate interstate commerce, and that the fee was an unconstitutional infringement on its rights. The Supreme Court disagreed, ruling that the federal government did indeed have the power to regulate interstate commerce. The Court held that the Commerce Clause of the Constitution gave Congress the power to regulate commerce between the states, and that the fee was a valid exercise of that power. The Court also held that the fee was not an unconstitutional infringement on the railroad's rights, as it was a reasonable means of regulating interstate commerce. The decision in United States v. New Orleans Railroad established the principle that the federal government has the power to regulate interstate commerce. This decision has been cited in numerous subsequent cases, and has been used to uphold a variety of federal laws that regulate interstate commerce.

In United States v. New Orleans Railroad, the Supreme Court was tasked with determining whether a federal tax on railroad companies applied to those that operated within state boundaries. The majority opinion held that Congress had the power to impose such taxes under its authority in Article I of the Constitution and thus affirmed the lower court's decision. Justice Field dissented from this ruling, arguing that it violated both due process and equal protection clauses of the Fourteenth Amendment by treating railroads differently than other businesses operating within state borders. He further argued that if Congress could impose such taxes without regard for states' rights, then it would be able to effectively control all aspects of commerce throughout each state - an outcome he deemed unconstitutional as well as contrary to public policy.