Habeas Corpus Act 1679

The Habeas Corpus Act 1679 received royal assent on 27 May 1679 and strengthened the ancient prerogative writ of habeas corpus by defining its scope and setting out clear procedures for its use, requiring courts to examine directly whether a prisoner's detention was actually lawful and so guarding against unlawful or arbitrary imprisonment. The writ of habeas corpus itself was already centuries old, its use traceable back to guarantees in Magna Carta of 1215, but before 1679 it had lacked consistent and enforceable procedure; this Act supplied that missing mechanism. It is regarded as one of the most important statutes in English constitutional history, a foundational protection against arbitrary detention by the state, and it remains part of English law today, still in force despite subsequent amendment.