"Habeas corpus" has certain limitations. Though a writ of right, it is not a writ of course. It is technically only a procedural remedy; it is a guarantee against any detention that is forbidden by law, but it does not necessarily protect other rights, such as the entitlement to a fair trial. So if an imposition such as internment without trial is permitted by the law, then "habeas corpus" may not be a useful remedy. In some countries, the writ has been temporarily or permanently suspended under the pretext of a war or state of emergency, for example by Abraham Lincoln during the American Civil War.