Sherlock et al. v. Alling, Administrator 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 mandamus to a federal court. The case involved a dispute between the heirs of a deceased man, who had left a will that was contested by the heirs. The state court had issued a writ of mandamus to the federal court, ordering it to hear the case. The Supreme Court held that the state court did not have the authority to issue the writ of mandamus to the federal court, as the federal court had exclusive jurisdiction over the case. The Court also held that the state court had no authority to interfere with the proceedings of the federal court. The Court concluded that the writ of mandamus was invalid and that the state court had no authority to issue it.

In the case of Sherlock et al. v. Alling, Administrator, the Supreme Court was asked to decide whether a contract between two parties could be enforced in court despite one party having died before it was executed and delivered. The majority opinion held that such contracts were not enforceable because they had not been fully performed by both parties prior to death; however, Justice Field dissented from this ruling on the grounds that there is no reason why a contract should not be binding if all conditions have been met except for delivery of the document itself. He argued that since performance of an agreement does not necessarily require physical delivery or possession of its terms, but rather can simply involve mutual assent and consideration being exchanged between two parties, then any contract which has satisfied these requirements should still be considered valid even if one party dies before delivering their part of it.