Moffat & Another v. United States was a case heard by the United States Supreme Court in 1884. The case involved a dispute between the United States and two individuals, Moffat and another, over the ownership of certain land in the state of California. The United States had acquired the land from Mexico in 1848, and had subsequently granted it to Moffat and the other individual. However, the United States later sought to reclaim the land, arguing that the grant was invalid because it had been made without the approval of Congress. The Supreme Court ultimately sided with the United States, ruling that the grant was invalid because it had been made without the approval of Congress. The Court held that the United States had the right to reclaim the land, as it had been acquired from Mexico in 1848. The Court also held that the grant was invalid because it had been made without the approval of Congress, and that the United States had the right to reclaim the land. In conclusion, the Supreme Court ruled in favor of the United States, holding that the grant of land to Moffat and the other individual was invalid because it had been made without the approval of Congress. The Court also held that the United States had the right to reclaim the land, as it had been acquired from Mexico in 1848.

In the case of Moffat & Another v. United States, the Supreme Court was tasked with determining whether a federal statute that imposed an income tax on certain types of corporate dividends violated the Fifth Amendment's protection against double taxation. The majority opinion held that it did not violate this provision and thus upheld the law in question. However, Justice Field dissented from this decision, arguing that Congress had exceeded its authority by imposing such a tax without providing any compensation to those affected by it. He further argued that if Congress were allowed to impose taxes without providing compensation for them then they would be able to take away property rights at will and thereby undermine fundamental constitutional principles like due process and equal protection under the law. Ultimately, he concluded that allowing such taxation would lead to "the destruction of all private rights."