The Santissima Trinidad and the St. Ander was a case heard by the United States Supreme Court in 1822. The dispute arose when two Spanish vessels, the Santissima Trinidad and the St. Ander, were captured by an American privateer during wartime hostilities between Spain and America in 1819. The owners of both ships sued for damages from their capture on grounds that they had been neutral vessels at the time of capture, but this claim was rejected by a jury trial due to lack of evidence proving neutrality status at sea or any other legal justification for immunity from seizure under international law principles governing maritime warfare. Ultimately, Chief Justice John Marshall delivered a unanimous opinion affirming that there must be clear proof presented before any vessel can be considered immune from seizure as a neutral ship during times of war; otherwise it is subject to lawful capture according to established rules of naval warfare applicable among nations engaged in armed conflict with one another.

In the dissenting opinion for The Santissima Trinidad, and the St. Ander case, Justice Story argued that a neutral vessel should not be liable to capture or condemnation in a war between two belligerent nations unless it is actually engaged in hostile acts against one of them. He reasoned that if such vessels were subject to seizure without any proof of hostility, then they would become easy prey for either side and their neutrality would be rendered meaningless. Furthermore, he noted that this could lead to an increase in maritime warfare as each nation sought out more prizes from neutral ships than from enemy ones. In conclusion, Justice Story maintained that while there may have been some evidence suggesting the presence of contraband on board the Santissima Trinidad and St. Ander vessels at issue here, it was insufficient to justify their capture or condemnation by either belligerent party without further proof of actual hostilities being committed against them first.