The sober and thorough Congressional Research Service released today legislative attorney Jennifer K. Elsea’s sober and thorough analysis of whether U.S. citizens and residents may be detained under the Authorization for Use of Military Force (AUMF). Elsea’s sober and thorough conclusion:
If Hamdi stands for the proposition that U.S. citizens may be detained under the same circumstances that make non-citizens amenable to law-of-war detention, regardless of location, then the Guantanamo cases may provide sufficient legal precedent for detaining similarly situated persons within the United States. If, on the other hand, historical precedent has any bearing on the interpretation of the state of the law and authorities regarding detention of U.S. persons under the law of war, as preserved by section 1021(e) of the 2012 NDAA, it seems difficult to conclude that the AUMF should be read to imply the authority to detain such persons unless they are part of the armed forces of a belligerent party to an armed conflict.
This is consistent with Elsea’s analysis in a 2005 CRS report, Detention of American Citizens as Enemy Combatants, where she informed Congress that historically, even during declared wars, citizens who were not members of enemy armed forces arrested not on the battlefield could not be detained without additional statutory authority; the authorization to use force was not, in and of itself, enough. Here is the full CRS report Detention of U.S. Persons as Enemy Belligerents.