In Louisiana v. United States, the Supreme Court was asked to decide whether the United States had the right to sue the state of Louisiana for failing to comply with a treaty. The treaty in question was the Convention of 1803, which had been signed between the United States and France. The treaty provided that the United States would have the right to navigate the Mississippi River and its tributaries. The United States argued that Louisiana had violated the treaty by passing a law that prohibited the navigation of the Mississippi River by foreign vessels. The Supreme Court held that the United States had the right to sue Louisiana for violating the treaty. The Court reasoned that the treaty was a valid contract between the two countries and that the United States had the right to enforce it. The Court also held that the United States had the right to sue Louisiana for damages caused by the violation of the treaty. The Court noted that the United States had suffered economic losses due to the state's violation of the treaty and that it was entitled to compensation for those losses. In the end, the Supreme Court held that the United States had the right to sue Louisiana for violating the treaty and that it was entitled to damages for the losses it had suffered. This case established the principle that the United States has the right to enforce treaties it has signed with foreign countries.

Justice Field delivered the dissenting opinion in Louisiana v. United States, arguing that Congress had no power to pass a law regulating navigation on navigable waters within a state's boundaries. He argued that this was an issue of police power which belonged exclusively to the states and could not be regulated by Congress under its enumerated powers. Furthermore, he asserted that if such regulation were allowed it would lead to federal control over all aspects of life within each state and thus undermine the sovereignty of individual states. He concluded his dissent by noting that while he did not dispute the need for some form of national regulation over interstate commerce, it should only extend as far as necessary for its purpose and should never encroach upon matters reserved solely for state governments.