Habeas Corpus, in the Federal Court, is a petition that claims that you are being detained against your US constitutional rights. In United States law, habeas corpus is a recourse challenging the reasons or conditions of a person's confinement under color of law.A Writ of Habeas Corpus is a civil proceeding that is available in both State and Federal Court to challenge the legality of imprisonment. This Chapter discusses how the writ of habeas corpus is applied in three states: Florida, New York, and Michigan. The "Great Writ" of habeas corpus is a fundamental right in the Constitution that protects against unlawful and indefinite imprisonment. Latin for "that you have the body. Writ of Habeas Corpus. What is Habeas Corpus? (hay-bee-us core-puss) n. LAW"). 3. Other ways of attacking your conviction include filing an appeal, or a state or federal writ of habeas corpus.