In Diouf II, the U.S. Court of Appeals for the Ninth Circuit held that prolonged detention under 8 U.S.C. 1231(a)(6) raises serious constitutional concerns, which require additional procedural safeguards beyond those provided under the regulations. Section 1231(a)(6) authorizes detention of an alien subject to a removal order if the government is not able to physically remove the alien within the initial 90 days after the order becomes final.
Under the regulations, ICE officers periodically determine whether aliens subject to final removal orders should remain in detention or be released on bond or other conditions. Detention under this regime may continue for years. ICE follows these procedures because the Supreme Court held in Zadvydas v. Davis, 533 U.S. 678 (2001) that the government could not indefinitely detain aliens subject to final removal orders, at least where removal is not reasonably foreseeable.
Diouf II, however, holds that the procedures adopted by ICE are not sufficient where the detention significantly exceeds six months. It holds that an alien subject to final removal order must receive a bond hearing before a neutral immigration judge where removal is not imminent and the alien has been detained for six months. Further, it holds that the alien should receive bond unless ICE establishes to the satisfaction of the immigration judge that the alien is a flight risk or poses a danger to the community.
These are the same safeguards that the Ninth Circuit found necessary for aliens subject to prolonged detention under 8 U.S.C. 1226(a) (detention during direct challenge to a removal order). See Casas-Castrillon v. Department of Homeland Security, 535 F.3d 942 (9th Cir. 2008).
Read the opinion at http://www.ca9.uscourts.gov/datastore/opinions/2011/03/07/09-56774.pdf.