Sargent & Others v. Helton & Others 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 two parties over a contract for the sale of land in the state of Tennessee. The plaintiffs, Sargent & Others, sought to enforce the contract by filing a suit in the state court. The defendants, Helton & Others, argued that the state court did not have the authority to issue a writ of mandamus to the federal court. The Supreme Court held that the state court did not have the authority to issue a writ of mandamus to the federal court. The Court reasoned that the state court lacked the power to issue a writ of mandamus to the federal court because the federal court was a court of exclusive jurisdiction. The Court further held that the state court could not interfere with the proceedings of the federal court. The Court's decision in this case established the principle that state courts do not have the authority to issue a writ of mandamus to a federal court. This decision has been cited in numerous cases since then, and it remains an important precedent in the area of federal-state court relations.

Justice Field delivered the dissenting opinion in Sargent & Others v. Helton & Others, arguing that the majority's decision was contrary to established precedent and would lead to a dangerous expansion of federal power. He argued that Congress had no authority under the Constitution to pass laws regulating private property rights within a state, as it did with this case, which involved an act passed by Congress concerning land titles in California. Furthermore, he asserted that such legislation violated both due process and equal protection clauses of the Fourteenth Amendment because it interfered with existing contracts between citizens without their consent or knowledge. Finally, Justice Field argued that if Congress were allowed to regulate these matters then there would be no limit on its powers since any matter could be deemed "necessary" for public welfare or safety purposes. In conclusion, he believed that allowing this law to stand would result in an unconstitutional expansion of federal power at the expense of states' rights and individual liberties.