In the case of Nelson, Warden v. George in 1969, the United States Supreme Court ruled that a state prisoner could not use federal habeas corpus to challenge his confinement unless he had exhausted all available state remedies or demonstrated exceptional circumstances. The petitioner was an inmate who sought relief from his conviction on grounds that it violated his constitutional rights. However, he had not pursued all possible avenues for appeal within the California court system before seeking federal intervention. The Supreme Court held that under existing law (28 U.S.C §2254), prisoners must first exhaust their options at the state level before turning to federal courts for help unless there are special reasons why this would be ineffective or inadequate.

In the dissenting opinion for Nelson, Warden v. George (1969), Justice Harlan argued that the majority's decision to allow federal courts to intervene in state court proceedings was a departure from traditional principles of federalism and comity. He contended that such intervention should only be allowed when there is an ongoing violation of constitutional rights or when state remedies are inadequate or ineffective. In this case, he believed neither condition had been met as George had not exhausted all his available state remedies before seeking relief in federal court. Furthermore, he asserted that allowing such interventions could potentially disrupt the functioning of state judicial systems by encouraging defendants to bypass them entirely and go straight to federal courts instead.