Habeas corpus is a Latin phrase meaning "produce the body. Federal habeas corpus is a procedure under which a federal court may review the legality of an individual's incarceration.The writ of habeas corpus, also known as the Great Writ, is a U.S. legal process that determines whether an offender's imprisonment is valid. In United States law, habeas corpus is a recourse challenging the reasons or conditions of a person's confinement under color of law. Filing a petition for habeas corpus means that you are arguing that your incarceration is unjust. Habeas corpus, or the Great Writ, is the legal procedure that keeps the government from holding you indefinitely without showing cause. What Are the Different Types of Writs? The writ of habeas corpus, the most celebrated writ in the English law. The "Great Writ" of habeas corpus is a fundamental right in the Constitution that protects against unlawful and indefinite imprisonment. In a petition for habeas corpus, a prisoner (or another interested party) raises doubts about the legality of his or her imprisonment.