United States v. Ferrary et al. was a United States Supreme Court case that dealt with the issue of whether the United States had the right to seize a vessel that was used to transport contraband goods. The case involved the seizure of a vessel called the "Ferrary" by the United States government. The vessel had been used to transport contraband goods from the United States to Mexico. The defendants argued that the seizure was illegal because the vessel was not owned by the United States and the contraband goods were not intended for sale in the United States. The Supreme Court held that the seizure was valid because the vessel was used to transport contraband goods and the goods were intended for sale in the United States. The Court reasoned that the United States had the right to seize the vessel because it was used to transport contraband goods and the goods were intended for sale in the United States. The Court also held that the seizure was valid because the vessel was owned by the United States and the contraband goods were intended for sale in the United States. In conclusion, the Supreme Court held that the seizure of the vessel was valid because the vessel was used to transport contraband goods and the goods were intended for sale in the United States. The Court reasoned that the United States had the right to seize the vessel because it was used to transport contraband goods and the goods were intended for sale in the United States. The Court also held that the seizure was valid because the vessel was owned by the United States and the contraband goods were intended for sale in the United States.

In United States v. Ferrary et al., the Supreme Court was asked to decide whether a Mexican citizen, who had been living in California since 1853 and acquired land there through a grant from Mexico, could be considered an alien enemy during the Civil War and thus subject to forfeiture of his property. The majority opinion held that he was indeed an alien enemy and therefore forfeited his property; however, Justice Field dissented on this point. He argued that because Ferrary had been living in California for so long prior to the war's outbreak - over ten years - he should not be treated as an alien enemy but rather as one of its citizens or inhabitants. Furthermore, Field noted that under international law at the time it would have been illegal for Mexico to declare war against another nation without first giving notice of such action; since no such notice had ever been given by either country before hostilities began between them during the Civil War, then Ferrary should not suffer any consequences due to their conflict. As such, Justice Field concluded that Ferrary's rights were violated when his property was taken away from him without proper cause or justification.