The United States v. The Cargo of the Ship Fanny, Jennings, Master was a case heard by the Supreme Court in 1815. It involved a dispute between the United States and an English vessel called The Fanny which had been seized for violating American neutrality laws during the War of 1812. At issue was whether or not goods on board were subject to forfeiture under US law as they had been shipped from England with knowledge that their destination would be enemy territory (the US). In its ruling, the court held that while it is true that goods may be forfeited if knowingly sent to an enemy country, this does not apply when those same goods are intended for neutral ports within such countries; thus no forfeiture could take place in this instance due to lack of evidence showing intent on behalf of either party. This decision established important precedent regarding international trade and maritime law which still stands today.

In the case of The United States v. The Cargo of the Ship Fanny, Jennings, Master (1815), Justice Story delivered a dissenting opinion that argued against the majority's decision to allow for an exception in admiralty law which allowed for goods on board a vessel to be seized and condemned as prize even if they were owned by citizens of neutral countries. According to Justice Story, this was contrary to established international law principles and would lead other nations into believing that America did not respect their rights or sovereignty. He further argued that such exceptions should only be made when there is clear evidence from both sides regarding ownership and it must also be proven beyond reasonable doubt that those goods are actually contraband or enemy property before any seizure can take place. In conclusion, he believed allowing such exceptions could potentially cause more harm than good in terms of foreign relations with other nations due to its disregard for international laws governing maritime trade.