The Schooner Hoppet and Cargo v. The United States was a case heard by the Supreme Court in 1813. It concerned a dispute between an American merchant vessel, the schooner Hoppet, and its cargo of goods against the United States government for damages caused by French privateers during wartime. The court found that under international law, France had violated America's neutrality rights when it allowed its privateers to attack neutral vessels like the Hoppet without warning or provocation. As such, they ruled that France must pay reparations to compensate for any losses suffered as a result of their actions. Furthermore, they held that since these violations occurred while America was at war with Britain (and not with France), no compensation could be sought from Britain itself - only from those responsible for violating American neutrality rights: namely France and her agents who attacked neutral vessels on behalf of their country during wartime operations

In The Schooner Hoppet and Cargo v. The United States, the Supreme Court was tasked with determining whether a vessel that had been seized by the U.S. Navy for violating an embargo imposed by President Thomas Jefferson could be considered a prize of war or if it should instead be treated as contraband subject to forfeiture under admiralty law. Justice William Johnson wrote a dissenting opinion in which he argued that since there was no state of war between the United States and Great Britain at the time, any seizure made on behalf of either nation would have to fall within their respective municipal laws rather than international law governing prizes taken during wartime conflicts. He further noted that even if such seizures were permissible under international law, they must still comply with domestic statutes enacted by Congress in order for them to be valid; otherwise they are deemed unlawful and thus cannot stand up in court proceedings against those who challenge them. Ultimately, Justice Johnson concluded that since this particular seizure did not meet these criteria it should therefore not qualify as a lawful prize but instead remain subject to forfeiture according to admiralty regulations established by Congress for cases involving violations of embargoes or other similar restrictions placed upon maritime commerce activities