Who Should Use This Form. You should use this form if.Writ of Habeas Corpus a civil case number and assign it to the judge assigned to the pending writ with the lowest case number. Habeas corpus is used to challenge the legality of the detention or restraint of a person and to obtain the person's prompt release. The "Great Writ" of habeas corpus is a fundamental right in the Constitution that protects against unlawful and indefinite imprisonment. —The writ of habeas corpus shall be grantable of right, freely and without cost. The writ may also be employed in a wide variety of situations not involving criminal proceedings. In specific circumstances, he also might be able to seek habeas corpus relief in state court or federal court.