King v. Worthington was a United States Supreme Court case that dealt with the issue of whether a state court had the authority to issue a writ of error to a federal court. The case involved a dispute between two parties, King and Worthington, over a contract for the sale of a steamboat. King had sued Worthington in a state court, and the state court had issued a writ of error to the federal court. Worthington argued that the state court did not have the authority to issue the writ of error, and the Supreme Court agreed. The Supreme Court held that the state court did not have the authority to issue the writ of error because the federal court had exclusive jurisdiction over the case. The Court reasoned that the state court was not a court of competent jurisdiction to issue the writ of error, and that the writ of error was therefore void. The Court also held that the state court had no authority to review the decision of the federal court. The Court's decision in King v. Worthington established that state courts do not have the authority to issue writs of error to federal courts. This decision has been cited in numerous cases since then, and it remains an important precedent in the area of federal court jurisdiction.

In the case of King v. Worthington, the Supreme Court was tasked with determining whether a contract between two parties could be enforced when it had been made without consideration. The majority opinion held that no consideration was necessary for such an agreement to be enforceable, while Justice Field dissented from this decision and argued that all contracts must have some form of consideration in order to be valid and binding under law. He reasoned that if agreements were allowed to stand without any sort of exchange or benefit given by either party, then individuals would not take their contractual obligations seriously as they would know there is nothing stopping them from breaking their promises at any time. Furthermore, he noted that allowing contracts without consideration could lead to fraud and other abuses since one party may promise something but never actually deliver on it due to lack of incentive or legal obligation. Therefore, Justice Field concluded that all contracts should require some form of mutual exchange in order for them to be legally binding upon both parties involved.