What Is Habeas Corpus? Habeas corpus is a kind of petition that you can file in federal court to claim that your imprisonment violates federal law.In United States law, habeas corpus is a recourse challenging the reasons or conditions of a person's confinement under color of law. What we are talking about, of course, is habeas corpus, a Latin phrase meaning "you should have the body. Habeas corpus is a centuriesold legal procedure that protects against unlawful and indefinite imprisonment. What Is Habeas Corpus? Habeas corpus is a kind of petition that you can file in federal court to claim that your imprisonment violates federal law. A definition of habeas corpus that includes the right to travel and embraces threats to liberty.