Pertinent summary of the constitutional basis for habeas corpus and its suspension,[1] and of the Habeas Corpus Suspension Act,[2] which may provide good background for the folks here:<p>[1]: <a href="https://constitution.congress.gov/browse/essay/artI-S9-C2-1/ALDE_00001087/" rel="nofollow">https://constitution.congress.gov/browse/essay/artI-S9-C2-1/...</a><p>[2]: <a href="https://en.wikipedia.org/wiki/Habeas_Corpus_Suspension_Act_%281863%29" rel="nofollow">https://en.wikipedia.org/wiki/Habeas_Corpus_Suspension_Act_%...</a><p>Habeas corpus is one of a class of legal vehicles known as extraordinary writs. Many of the ones that survive in American law (primarily in state courts — federal law has abolished writs like <i>audita querela</i>, <i>coram nobis</i>, <i>coram vobis</i>, etc.) tend to be appellate in nature, yet typically original actions in the appellate court. For example, writs of prohibition, mandamus, and certiorari are alive and well. Habeas and <i>quo warranto</i> (still common and used to challenge a governmental official's right to hold the office) are extraordinary writs and original actions, but usually initiated in the court of first instance (i.e., trial court).<p>The Annotated Constitution (see first link) is an excellent resource and worth bookmarking.