In Devereaux v. Marr, the Supreme Court of the United States ruled that a contract between two parties was binding even if it had not been signed by both parties. The case involved an agreement between James Devereaux and John Marr to purchase land in Kentucky from William Browning for $2,000. Although neither party had signed the agreement, they both agreed to its terms and began making payments on the property. When Browning refused to convey title after receiving payment in full, Devereaux sued Marr for breach of contract. The court held that since there was evidence of mutual assent between all three parties regarding their obligations under the agreement, it should be enforced as a valid contract regardless of whether or not it had been formally executed with signatures from each party involved.

In Devereaux v. Marr, the Supreme Court was tasked with determining whether a state court had jurisdiction over a case involving two citizens of different states. The majority opinion held that the state court did not have jurisdiction in this matter because it involved citizens from different states and thus fell under federal judicial power as outlined by Article III of the Constitution. However, Justice Story dissented from this ruling on the grounds that there were no clear provisions in either Article III or any other part of the Constitution which prohibited such an exercise of state judicial authority. He argued that if Congress had intended to limit such powers then they would have done so explicitly rather than leaving it up to interpretation by courts. Furthermore, he noted that allowing each individual State to decide matters between its own citizens without interference from other States would be beneficial for both parties since they could receive justice more quickly and efficiently than through federal proceedings which often take longer due to their complexity and scope.