Sands v. Edmunds was a United States Supreme Court case that addressed the issue of whether a state court could issue a writ of habeas corpus to a prisoner who was being held in federal custody. The case arose when a prisoner, Sands, was held in federal custody in the District of Columbia. Sands sought a writ of habeas corpus from the Supreme Court of the District of Columbia, which was denied. Sands then appealed to the Supreme Court of the United States. The Supreme Court held that the state court did not have the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The Court reasoned that the writ of habeas corpus was a federal prerogative, and that the state court did not have the authority to interfere with the federal government's power to detain a prisoner. The Court also noted that the writ of habeas corpus was a fundamental right, and that the state court should not be allowed to interfere with the federal government's power to protect this right. The Court's decision in Sands v. Edmunds established that state courts do not have the authority to issue writs of habeas corpus to prisoners held in federal custody. This decision has been cited in numerous subsequent cases, and has been used to support the principle that the federal government has the power to protect the fundamental right of habeas corpus.

Justice Field delivered the dissenting opinion in Sands v. Edmunds, arguing that the majority's decision was contrary to established precedent and would lead to an unjust result. He argued that a court of equity should not be bound by strict rules of law when it comes to matters involving trusts, as they are inherently equitable proceedings. The trust created by William Sands' will had been accepted by his executors and trustees without any objection from either party for over forty years before this case arose; thus, Justice Field reasoned that it should remain intact despite any technical defects or irregularities with its formation. Furthermore, he noted that if the trust were invalidated due to these issues then both parties would suffer greatly since there was no other way for them to receive their respective shares of William Sands' estate. Therefore, Justice Field concluded that a court of equity must take into account all relevant circumstances surrounding a particular case in order to reach an equitable outcome rather than relying solely on rigid legal principles which may produce inequitable results under certain conditions.