Secretary of State Marco Rubio facilitated the arrest and detention of lawful permanent resident and college student, Mohsen Mahdawi. He did so not because Mahdawi allegedly committed a crime or other deportable offense, but for the seemingly sole reason that Mahdawi’s “pro-Palestinian protests” and advocacy stirred the Trump administration to anger. The Secretary claims he can trigger the arrest and detention of Mr. Mahdawi under a Cold War–era statute giving the secretary of state the power to initiate deportation proceedings against anyone he “personally determines” is contrary to America’s “foreign policy interest.” And he argues this power extends even to deporting permanent residents for protected speech. It does not.

Mahdawi petitioned a federal court to order his release, and that court ruled in his favor. Now the case is on appeal to the Second Circuit, where Cato has joined a broad coalition of groups, led by FIRE, to file an amicus brief supporting him. In our brief, we explain that noncitizens residing in the United States have the same First Amendment rights as citizens. The Supreme Court said as much in Bridges v. Wixon (1945), where the Court remarked that “freedom of speech and of press is accorded aliens residing in this country.” And the Supreme Court also affirmed this principle in Bridges v. California (1941), a case in which the Court invalidated the criminal convictions of several people, including a non-citizen, because those convictions violated the First Amendment.

As our brief further explains, Mahdawi’s advocacy was protected speech. The government has not alleged that Mahdawi was providing material support to terrorists, nor has it alleged that his advocacy fell into any other exception to the First Amendment (such as insurrectionary speech). If a citizen were punished for the same advocacy, such punishment would be a blatant First Amendment violation. Mahdawi’s punishment is no different.

Finally, our brief emphasizes that Mahdawi’s detention is irreconcilable with the Supreme Court’s admonition that colleges and their “surrounding environs” are “peculiarly the ‘marketplace of ideas.’” There are more than a million international students studying at America’s universities. None of them will feel safe criticizing the American government —in class, scholarship, or on their own time—if a current or future secretary of state may, at his unreviewable discretion, arrest and detain them based on their spoken or written advocacy.

As Justice Frank Murphy wrote in a concurrence in the Wixon case, the freedom of foreign nationals lawfully residing in the United States is “not dependent upon their conformity to the popular notions of the moment,” because the First Amendment “belongs to them as well as to all citizens.” Mahdawi’s detention violates the First Amendment, and the Second Circuit should affirm the district court’s decision in his favor.