Mobile v. Watson was a United States Supreme Court case that addressed the issue of whether a state court had the authority to issue a writ of error to a federal court. The case arose when the state of Alabama attempted to issue a writ of error to the United States Circuit Court for the Southern District of Alabama. The Circuit Court had previously ruled in favor of Watson in a case involving a contract dispute between Watson and Mobile. The Supreme Court held that the state court did not have the authority to issue a writ of error to the federal court. The Court reasoned that the state court lacked jurisdiction over the federal court, and that the writ of error was an attempt to exercise jurisdiction over the federal court. The Court further held that the writ of error was an attempt to review the decision of the federal court, which was beyond the scope of the state court's authority. The Court's decision in Mobile v. Watson established that state courts do not have the authority to issue writs of error to federal courts. This decision has been cited in numerous subsequent cases, and has been used to support the principle that state courts cannot interfere with the decisions of federal courts.

Justice Field delivered the dissenting opinion in Mobile v. Watson, arguing that the majority had incorrectly interpreted a state statute and disregarded long-standing precedent. He argued that states have traditionally been allowed to pass laws governing their own internal affairs, including those related to property rights and inheritance. The Alabama legislature had passed a law allowing for an heir of an intestate estate to receive all of his or her share before any other heirs received theirs; this was done with the intention of protecting widows and children from being deprived of their rightful inheritances due to creditors' claims on estates. Justice Field argued that it was not within the purview of federal courts to interfere with such matters as they were strictly within state jurisdiction. Furthermore, he noted that there were no constitutional issues at stake here since both parties involved in this case were citizens of Alabama; thus, he concluded that it should be up to Alabama's courts—not federal ones—to decide how best to interpret its statutes regarding inheritance rights.