Arnson and Another v. Murphy, Collector was a United States Supreme Court case that dealt with the issue of whether a tax imposed by the United States on the importation of goods was constitutional. The case was brought by two merchants, Arnson and another, who had imported goods from abroad and were required to pay a tax on the goods. The merchants argued that the tax was unconstitutional because it was not authorized by the Constitution. The Supreme Court held that the tax was constitutional. The Court reasoned that the power to tax imports was an implied power of the federal government, and that the tax was necessary to raise revenue for the government. The Court also held that the tax was not a violation of the merchants' rights under the Constitution. In conclusion, the Supreme Court held that the tax imposed by the United States on the importation of goods was constitutional. The Court reasoned that the power to tax imports was an implied power of the federal government, and that the tax was necessary to raise revenue for the government. The Court also held that the tax was not a violation of the merchants' rights under the Constitution.

In Arnson and Another v. Murphy, Collector, the Supreme Court was asked to decide whether a tax imposed by Congress on certain imported goods violated the Constitution. The majority opinion held that the tax did not violate any constitutional provisions because it was within Congress’s power to impose taxes for revenue purposes. However, Justice Field dissented from this decision and argued that while Congress had authority to impose taxes for revenue purposes, they could not do so in such an arbitrary manner as to interfere with international commerce or discriminate against foreign nations or their citizens. He further argued that since this particular tax interfered with international trade and discriminated against foreign countries and their citizens, it should be declared unconstitutional under Article I of the Constitution which grants exclusive powers over interstate commerce solely to Congress.