Stovall v. Banks was a United States Supreme Court case that was decided in 1870. The case involved a dispute between two parties over a contract for the sale of a slave. The plaintiff, Stovall, had entered into a contract with the defendant, Banks, to purchase a slave for $1,000. Stovall paid Banks $500 as a down payment and agreed to pay the remaining $500 at a later date. Banks then sold the slave to a third party without informing Stovall. Stovall sued Banks for breach of contract, claiming that Banks had failed to fulfill his obligations under the contract. The Supreme Court held that Banks was liable for breach of contract. The Court found that Banks had failed to fulfill his obligations under the contract and had acted in bad faith by selling the slave to a third party without informing Stovall. The Court also held that Stovall was entitled to damages for the breach of contract. The Court awarded Stovall the full amount of the purchase price, plus interest, as damages for the breach of contract. This case is significant because it established the principle that a party who breaches a contract is liable for damages. It also established that a party who acts in bad faith can be held liable for damages. This case is also significant because it was one of the first cases to involve a dispute over the sale of a slave.

In Stovall v. Banks, the Supreme Court was tasked with determining whether a state court had jurisdiction to try an accused for murder when he had been arrested in another state and brought back to the original state by federal officers. The majority opinion held that such jurisdiction did exist, but Justice Field dissented from this decision. He argued that since no crime had been committed within the boundaries of the original state, it could not exercise criminal jurisdiction over someone who was arrested outside its borders and then returned there by federal agents. Furthermore, Field reasoned that allowing states to do so would be contrary to both constitutional principles and public policy as it would allow them too much power over citizens of other states without their consent or representation in those courts. In conclusion, Justice Field believed that only Congress has authority under Article IV Section 2 Clause 2 of the Constitution (the Extradition Clause) to determine if a person can be extradited across jurisdictional lines for trial on criminal charges; thus any attempt by a State court to assume such authority is unconstitutional and should not be allowed