A provision of the immigration laws, 8 U.S.C. § 1226(c), directs immigration authorities to detain noncitizens with certain criminal convictions while their deportation proceedings are pending, regardless of whether the particular person detained actually can be shown to pose any risk of flight or danger to others. The deportation process can take months or years to carry out, particularly when individuals seek relief from deportation on the grounds that they will be persecuted or tortured if deported.

After spending more than fourteen months in this type of immigration detention, the detainee in this case filed suit to challenge the constitutionality of his ongoing detention, arguing that such prolonged imprisonment requires a hearing before a neutral decisionmaker to determine whether he can safely be released on bond. The district court disagreed, and the detainee appealed that ruling to the U.S. Court of Appeals for the Second Circuit, where CAC filed an amicus brief urging reversal. In May 2024, the Second Circuit ruled that the detainee’s “unreasonably prolonged detention” without a bond hearing violated the Due Process Clause, emphasizing that Supreme Court precedent has allowed only brief periods of mandatory detention for noncitizens who are in deportation proceedings. The government unsuccessfully sought en banc review of the decision from the full Second Circuit and then petitioned the Supreme Court, which agreed to review the case. In September 2026, CAC filed an amicus brief in support of the detainee.

Our brief explains that the Fifth Amendment protects noncitizens as fully as citizens—shielding every “person” (not just every “citizen”) from deprivations of life, liberty, or property without due process of law. While the government may deport noncitizens who are ineligible to remain in this country, it must respect the safeguards of due process when exercising that authority. And one of the core protections that due process guarantees, for citizens and noncitizens alike, is freedom from arbitrary, prolonged imprisonment.

Indeed, the historical common law that informed the authors of the Due Process Clause protected noncitizens as fully as citizens from arbitrary and prolonged detention. Under English common law, noncitizens had the same access to legal process as citizens to defend their rights and personal liberty, including the same ability to secure release from unjustified detention. The law did not single out noncitizens for any kind of confinement resembling modern mandatory immigration detention. After American independence, the same common-law safeguards against arbitrary and prolonged detention protected noncitizens in America, too.

The Due Process Clause was meant to preserve these common-law safeguards, not displace them. While some constitutional provisions distinguish citizens from noncitizens, the Fifth Amendment speaks in a universal register, providing that “no person” may be deprived of liberty without due process. Consistent with the history that informed the meaning of the Amendment, the Due Process Clause forbids prolonged imprisonment pending deportation hearings with no opportunity for bail. The Supreme Court should affirm the Second Circuit’s holding that prolonged immigration detention without so much as a bond hearing violates the Constitution.