Habeas Corpus

Habeas corpus is shorthand for a variety of writs or legal pleadings seeking to bring a person within a court's power. Of the many habeas corpus writs, the most celebrated and significant is the writ of habeas corpus ad subjiciendum, the "Great Writ," which requires an official or person who holds another in custody to produce the person so that a court can inquire into the legality of the detention. In contemporary practice, this writ is most commonly used to challenge the legality of criminal convictions and sentences, though it is also used to challenge the legality of pretrial detentions and the legality of custody in other settings, including immigration, mental health, and military contexts. Other habeas writs are available for distinct purposes, such as to make a prisoner available to testify in court (ad testificandum) or to ensure that a prisoner is brought before the proper court for prosecution (ad prosequendum).