In the United States Supreme Court case of The United States v. Rafael Garcia, the court was tasked with determining whether a Mexican citizen who had been living in California since 1846 and had become a naturalized citizen of Mexico in 1852 could be considered an alien under U.S. law and thus subject to deportation proceedings initiated by the federal government. The court held that although Garcia was not an American citizen, he did have certain rights as a resident alien which included protection from being deported without due process of law or just cause for removal from his adopted home state of California. Furthermore, it found that any attempt to deport him would violate his right to remain in the country until such time as Congress passed legislation authorizing his removal or deportation on grounds consistent with international treaties between Mexico and America at that time.

In United States v. Garcia, the Supreme Court was asked to decide whether a Mexican citizen who had been living in California since before it became part of the United States could be convicted under federal law for failing to register as an alien. The majority opinion held that he could not because Congress did not have authority over foreign citizens residing within states at the time of their admission into the Union. Justice Curtis dissented from this decision, arguing that Congress has broad power over immigration and naturalization matters and can pass laws applicable to all persons regardless of citizenship status or place of residence when they enter a state after its admission into the Union. He argued further that if aliens were exempt from such laws then there would be no way for Congress to regulate immigration or protect national security interests related thereto.