A legal term from the 14th century or earlier. Refers to a number of legal writs to bring a person before a court or judge, most commonly habeas corpus ad subjiciendum (you may have the body to bring up). Commonly used as the general term for a prisoner's legal right to challenge the legality of their detention. (Corpus here is used in a similar sense to corpus delicti, referring to the substance of the reason for detention rather than a physical human body.)
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