The United States v. Nicholl was a Supreme Court case in which the defendant, John Nicholl, had been convicted of violating the Non-Intercourse Act of 1809 by trading with Spanish vessels on the Mississippi River. The government argued that this act gave them exclusive control over trade between foreign nations and American citizens and that any violation should be punished as piracy. The court ruled in favor of Nicholl, finding that Congress did not have authority to pass such an act because it violated Article I Section 10 Clause 2 of the Constitution which states “No State shall…pass any Bill of Attainder or ex post facto Law”. This ruling established important precedent for future cases regarding Congressional power to regulate commerce between foreign countries and American citizens without infringing upon state rights under the Constitution.

In The United States v. Nicholl, the Supreme Court was asked to determine whether a federal court had jurisdiction over an alleged violation of maritime law that occurred on board a vessel in the territorial waters of Louisiana. Chief Justice John Marshall delivered the dissenting opinion, arguing that Congress did not have authority under Article III of the Constitution to grant such jurisdiction and thus it should be left up to state courts. He argued that since this case involved only matters within one state's boundaries, there was no need for federal intervention and any decision made by a state court would be binding upon all parties regardless of their residence or citizenship status. Furthermore, he noted that if Congress were allowed to extend its power beyond what is expressly granted in Article III then it could potentially interfere with states' rights and undermine principles established by our Founding Fathers when they wrote the Constitution.