Levy v. Dangel 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 habeas corpus to a prisoner who was being held in a federal prison. The case arose when a prisoner, Levy, was held in a federal prison in New York and sought a writ of habeas corpus from a state court. The state court granted the writ, and the federal government appealed the decision to the Supreme Court. The Supreme Court held that the state court did not have the authority to issue the writ of habeas corpus. The Court reasoned that the writ of habeas corpus was a federal power, and that the state court did not have the authority to interfere with the federal government's power to imprison individuals. 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 Levy v. Dangel established that state courts do not have the authority to issue writs of habeas corpus to prisoners held in federal prisons. This decision has been cited in numerous cases since then, and has been used to support the idea that the federal government has the power to protect the fundamental right of habeas corpus.

Justice Harlan wrote the dissenting opinion in Levy v. Dangel, a case concerning whether or not an individual can be held liable for damages caused by their negligence when they are acting as agents of another person. Justice Harlan argued that the majority's decision was wrong because it failed to consider the fact that under common law principles, an agent is responsible for any damage done while performing duties on behalf of their principal. He further noted that this principle had been recognized and applied in numerous other cases and should have been considered here as well. In addition, he pointed out that if individuals were allowed to escape liability simply by claiming they were acting on someone else's behalf then there would be no incentive for them to act responsibly or take reasonable care when carrying out tasks delegated to them by others. Therefore, Justice Harlan concluded his dissent with a call for the Court to reconsider its ruling and hold agents accountable according to established legal precedent rather than creating new rules which could lead to confusion and uncertainty about who is ultimately responsible for negligent actions taken on another’s behalf