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This article examines the appropriate and inappropriate role of "preventive detention" in responding to terrorist threats. It offers a constitutional jurisprudence of preventive detention, maintaining that absent a showing that dangerous behaviour cannot be addressed through criminal prosecution, preventive detention is unconstitutional. But criminal prosecution is not always a realistic option, and in those circumstances, preventive detention, carefully circumscribed and meticulously safeguarded by procedural protections, may be permissible. Familiar examples of accepted preventive detention regimes include civil commitment of dangerous persons who because of a mental disability cannot be held criminally responsible, and detention of enemy soldiers in a traditional war, whose hostile activities cannot be criminalized so long as they respect the laws of war.

The article argues that the contemporary debate over preventive detention often disregards the fact that US law already authorizes preventive detention in a variety of circumstances – as indeed do the laws of virtually every other nation. Thus, the proper question is not whether we should have preventive detention at all, but under what circumstances and pursuant to what protections. Unlike torture, preventive detention is not susceptible to an absolute prohibition.

I address the use and abuse of preventive detention since 9/11, and suggest a variety of reforms to forestall abuses in the future, particularly in the aftermath of another terrorist attack. I advocate reform of immigration law, the material witness law, and the “enemy combatant” detention authority. With respect to the latter, I find unsatisfactory the proposals of both those who call for a new preventive detention statute addressed to "suspected terrorists," such as Profs. Neal Katyal and Jack Goldsmith, and those who insist that the United States must either "try or release" everyone at Guantanamo (and presumably Bagram Air Force Base), as have several human rights organizations.

Instead, I suggest that a detention regime carefully restricted to persons engaged against us in the armed conflict with al Qaeda and the Taliban in Afghanistan would be consistent with the Constitution and international law, provided it included meticulous procedures designed to afford detainees a meaningful opportunity to defend themselves, and regular review of their status to ensure that they are detained no longer than necessary. The parameters of such a regime should be set forth by Congress, not improvised by the Executive. And the predicate for detention should be involvement in an ongoing armed conflict, not terrorism. Involvement in an armed conflict has long been a recognized justification for preventive detention, here and around the world. Terrorism, by contrast, is a crime, not different in kind from many other serious crimes, and can and should be addressed through the criminal justice system. However, where an act of terrorism leads to an armed conflict – as has happened only once in the 200-year history of the United States – the laws of war and the Constitution should permit carefully circumscribed preventive detention for the duration of the conflict.

Publication Citation

97 California Law Review 693 (2009)