The St. Lawrence, Webb, Master was a case heard by the United States Supreme Court in 1815. The claimants were M'Gregor and Penniman who argued that they had been wrongfully deprived of their property when it was seized by the British during the War of 1812. They claimed that since they were American citizens at the time of seizure, their property should have been protected under international law from being taken as prize or booty of war. The court ultimately ruled against them on two grounds: firstly because there was no evidence to prove that they were indeed American citizens at the time; and secondly because even if this could be proven, international law did not protect private property from capture in wartime unless it belonged to an enemy state or its subjects.

In The St. Lawrence, Webb, Master case, the Supreme Court was tasked with deciding whether a vessel captured by the British during the War of 1812 should be restored to its original owners or remain in possession of those who purchased it from them after capture. In a 5-4 decision, Justice Story delivered an opinion dissenting from that of Chief Justice Marshall and four other justices. He argued that there was no legal basis for restoring property taken by force during war as such action would violate public policy and encourage belligerents to seize private property without consequence. Furthermore, he noted that if restitution were allowed then purchasers would have no assurance their purchases were secure since they could potentially be reversed at any time due to changes in political circumstances beyond their control. As such he concluded that allowing restitution would create more harm than good and thus should not be permitted under law.