The Schooner Juliana v. The United States was a case heard before the Supreme Court in 1810. It involved a dispute between the owner of the schooner, John Hickey, and the United States government over whether or not Hickey had violated an embargo imposed by President Thomas Jefferson on all vessels leaving American ports for foreign destinations. The court ruled that while it was true that Hickey had violated the embargo, he could not be held liable because his actions were taken in good faith and with reasonable cause to believe they were legal under existing law at the time. This decision established an important precedent regarding how courts should interpret laws when determining liability for violations of them; namely, that even if someone has broken a law they can still avoid being found guilty if their actions were based on reasonable belief that those same actions did not violate any laws at all.

In The Schooner Juliana v. The United States, the Supreme Court was asked to decide whether a vessel could be seized for violating an embargo imposed by Congress. Chief Justice Marshall delivered the dissenting opinion of the court, arguing that it is unconstitutional for Congress to issue such embargoes without providing compensation or due process of law. He argued that although Congress has certain powers under Article I Section 8 of the Constitution, those powers are limited and do not include seizing private property without just compensation or due process. Furthermore, he noted that if such seizures were allowed then any citizen would be subject to arbitrary seizure at any time with no recourse available in a court of law. In conclusion, Chief Justice Marshall held that while Congress may have some power over commerce through its ability to regulate foreign trade and impose embargoes on vessels entering American ports from abroad; however this does not extend so far as allowing them seize private property without just cause or proper legal proceedings being followed first.