Refugio Palomar-Santiago, a lawful permanent resident, was removed from the United States in 1998 after a California felony-DUI conviction was treated as an aggravated felony. After Leocal v. Ashcroft later held that a comparable DUI was not a crime of violence, Palomar-Santiago returned to the United States and was charged with unlawful reentry. He sought dismissal by collaterally attacking the old removal order. The Supreme Court held that each requirement in the federal unlawful-reentry statute is mandatory: a defendant must show exhaustion of available administrative remedies, deprivation of an opportunity for judicial review, and fundamental unfairness in the removal order. The fact that the removal rested on a conviction later found not to be removable does not excuse the first two requirements. The substantive invalidity of an order is distinct from failure to exhaust or loss of judicial review, and the statute’s unambiguous text leaves no room for the proposed exception. The Court reversed the Ninth Circuit and remanded.