United States v. Murray is a United States Supreme Court case that was decided in 1879. The case involved the question of whether the United States government had the authority to impose a tax on the income of a foreign corporation. The defendant, Murray, was a British corporation that had been doing business in the United States. The government argued that it had the authority to impose the tax under the Constitution's Necessary and Proper Clause. The Supreme Court held that the government did have the authority to impose the tax. The Court reasoned that the Necessary and Proper Clause gave the government the power to impose taxes on foreign corporations doing business in the United States. The Court also noted that the tax was not discriminatory and did not violate any treaty obligations. In conclusion, the Supreme Court held that the government had the authority to impose a tax on the income of a foreign corporation doing business in the United States. The Court reasoned that the Necessary and Proper Clause gave the government the power to impose taxes on foreign corporations and that the tax was not discriminatory or in violation of any treaty obligations.

In United States v. Murray, the Supreme Court was asked to decide whether a criminal defendant could be convicted of an offense that had been committed before Congress passed a law making it illegal. The majority opinion held that since the act in question occurred prior to the passage of the statute, there was no legal basis for conviction and thus reversed and remanded. Justice Field dissented from this decision arguing that although Congress did not pass a law explicitly outlawing such conduct at the time of its commission, they had done so by implication when enacting subsequent statutes which made similar acts punishable offenses. He argued further that if Congress intended otherwise then they would have included language specifically exempting those who acted prior to its enactment from punishment; as such he believed it should be up to them rather than courts to determine whether or not individuals should be punished for actions taken before laws were passed prohibiting them.