For several centuries the Great Writ of Habeas Corpus has played a central role in protecting individual liberty, guarding against unlawful detention and against the exercise of power not in compliance with the law of the land. Central to the idea of habeas corpus is that it operates within the limits of unlawful imprisonment or detention. As the boundary line between lawful and unlawful confinement changes with growth in recognized individual rights, then the reach of the Great Writ also shifts.
Frank W. Smith Jr.,
Federal Habeas Corpus: State Prisoners and the Concept of Custody,
U. Rich. L. Rev.
Available at: https://scholarship.richmond.edu/lawreview/vol4/iss1/3