Generally speaking, the writ of habeas corpus is available in any case where the trial court has acted in excess of its jurisdiction. The inmate may file a petition for writ of habeas corpus.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. The Writ of Habeas Corpus protects prison inmates from false imprisonment to ensure people are not thrown into jail unlawfully. A writ of habeas corpus petition is a tool that individuals convicted of criminal offenses in California can use to challenge their imprisonment. This Chapter explains an important right—the writ of habeas corpus. Essentially, it's a safeguard against unlawful or arbitrary detention. Any prisoner, or another person acting on their behalf, may petition the court, or a judge, for a writ of habeas corpus. This order concerns 63 new petitions for a writ of habeas corpus related to the COVID19 outbreak at San Quentin State Prison.