The Writ of Habeas Corpus protects prison inmates from false imprisonment to ensure people are not thrown into jail unlawfully. How Do I Fill Out the Form?There is an official form (Judicial Council Form HC-001) for filing a state petition for writ of habeas corpus. Habeas corpus refers to the principle of freedom from unlawful detention. Follow the instructions below to fill out Petition for Writ of Habeas Corpus - ACLU of Northern California - aclunc online quickly and easily. They must have also filed a direct appeal to the appellate court and then to the California Supreme Court. At any point during an involuntary detention, a person may request a writ of habeas corpus.