In The United States, Appellants v. Eusebio M. Gomez, the Supreme Court heard a case involving an alleged violation of the Non-Intercourse Act of 1809 by Gomez. This act prohibited trade with foreign nations without congressional approval and was intended to protect American commerce from foreign competition during times of war or peace. In this case, it was argued that Gomez had violated the act by trading in goods with Spanish vessels while he resided in Florida which at that time belonged to Spain but later became part of America through treaty negotiations between both countries. The court ultimately found for the appellants and held that even though there were no specific laws prohibiting such activity when it occurred, it still constituted a violation as per general principles established under international law at that time and thus could be punished accordingly.

In the case of United States v. Eusebio M. Gomez, Chief Justice Marshall delivered a dissenting opinion in which he argued that the defendant was not guilty of violating an act passed by Congress to regulate trade and intercourse with Indian tribes because it did not apply to him as a Mexican citizen living on Mexican soil at the time of his alleged offense. He further stated that even if this law were applicable, there was no evidence presented during trial that proved beyond reasonable doubt that Gomez had committed any crime under its provisions. In conclusion, Marshall asserted that since no proof existed linking Gomez to any violation of federal law, he should be acquitted and set free from custody immediately.