Our Amicus Brief in W.M.M. v. Trump

Yesterday, we filed our amicus brief in W.M.M. v. Trump, an Alien Enemies Act case currently before the en banc Fifth Circuit. I coauthored the brief, submitted on on behalf of the the Cato Institute, the Brennan Center for Justice (NYU), legal scholars Geoffrey Corn and John Dehn, and myself. Geoffrey Corn and John Dehn are leading academic experts on national security law, and former Army officers and military lawyers. Prof. Corn was formerly the Army’s senior legal adviser on the law of war.

The brief builds on our earlier amicus brief in the same case, filed before a three-judge Fifth Circuit panel, which ruled against the Trump Administration. It argues that the it is illegal to use the Alien Enemies Act – which can only be invoked in the event of a war, invasion, or predatory incursion, or threat thereof – as a tool for peacetime deportation. Illegal migration and drug smuggling do not qualify as an “invasion” or “predatory incursion”; these terms refer to military attacks on US territory. And courts should not  defer to administration claims that an invasion has occurred, when it very obviously has not.

If courts endorse the broad definition of “invasion” advocated by the administration, dire consequences will follow. Border states would be able to engage in war against neighboring nations even without congressional authorization, and the federal government could suspend the writ of habeas corpus and detain people (including U.S. citizens) at will.

Parts of the brief draw on my new article, “Immigration is Not Invasion,” which analyzes the meaning of “invasion” under the Constitution and the Alien Enemies Act, in greater detail.