Are you being unlawfully detained by Immigration and Customs Enforcement? You may be able to file a petition for a writ of habeas corpus with a U.S. District Court. A petition for a writ of habeas corpus allows you to challenge the legality or length of your detention. You can challenge post-removal order detention, pre-removal order detention, and detention because you have been found to be inadmissible to the United States through a petition for a writ of habeas corpus. A petition for a writ of habeas corpus can also be used to challenge an order of removal.