Farney vs. Towle was a case heard by the United States Supreme Court in 1861. The dispute arose when William Farney, an African American man, sued John Towle for assault and battery after he had been attacked while attempting to board a public stagecoach in St. Louis County, Missouri. At issue before the court was whether or not Farney could bring suit against Towle under state law since he was an African American living as a free person in Missouri at the time of his attack; this question hinged on whether or not slavery existed within that jurisdiction according to federal law. In its decision, the court held that slavery did exist within St. Louis County and thus Farney's claim must be dismissed due to his status as an enslaved person at the time of his attack; however, it also noted that if circumstances were different such that Farney had been legally emancipated prior to being assaulted then he would have standing under state law and could pursue damages from Towle accordingly.

In Farney v. Towle, the Supreme Court was tasked with determining whether a state court had jurisdiction to hear a case involving an alleged breach of contract between two citizens of different states. The majority opinion held that the state court did not have jurisdiction because it violated Article III, Section 2 of the Constitution which grants exclusive federal judicial power over cases arising under diversity of citizenship. Justice Wayne dissented from this decision and argued that while Congress has authority to regulate matters concerning diversity jurisdiction, they cannot take away or limit any existing rights granted by state courts in such matters as long as those rights are consistent with constitutional principles and do not conflict with congressional legislation. He further argued that since there is no evidence suggesting Congress intended to interfere with pre-existing state laws regarding diversity jurisdiction when passing their legislation on this matter, then it should be assumed that these laws remain valid and enforceable within each respective State's borders.