Habeas corpus is a legal rule that requires a prisoner be presented in court and that the arrester prove that there is proper cause for detaining the prisoner. The Writ of Habeas Corpus demands that requires a prisoner must go before the court to determine if there is lawful authority to detain the prisoner."Habeas corpus" is a Latin term meaning "bring us the body. Habeas corpus is a legal action in which a prisoner challenges the authority of the jail or prison to continue holding him. The Habeas Corpus petition claims the arrest, sentence, or trial violated constitutional law, making imprisonment unlawful. "Habeas corpus" is a Latin term meaning "bring us the body. When a person petitions for a writ of habeas corpus in a custody matter, the technical legal rights of a parent are not central. The purpose of this order is to ensure that the detainee is not being held unlawfully or without sufficient cause. This means that you can only file a federal habeas petition if you have already lost your state direct appeal and your state post-conviction proceedings. The term in Latin means "show me the body.