As U.S. citizens, they have a constitutional right to re-enter the United States. As the Supreme Court noted in
Saenz v. Rowe, 526 U.S. 489, 498-99 (1999),
The word "travel" is not found in the text of the Constitution. Yet the "constitutional right to travel from one State to another" is firmly embedded in our jurisprudence.
United States v.
Guest, 383 U. S. 745, 757 (1966). Indeed, as Justice Stewart reminded us in
Shapiro v.
Thompson, 394 U. S. 618 (1969), the right is so important that it is "assertable against private interference as well as governmental action ... a virtually unconditional personal right, guaranteed by the Constitution to us all."
Id., at 643 (concurring opinion). In
Shapiro, we reviewed the constitutionality of three statutory provisions that denied welfare assistance to residents of Connecticut, the District of Columbia, and Pennsylvania, who had resided within those respective jurisdictions less than one year immediately preceding their applications for assistance. Without pausing to identify the specific source of the right, we began by noting that the Court had long "recognized that
the nature of our Federal Union and our constitutional concepts of personal liberty unite to require that all citizens be free to travel throughout the length and breadth of our land uninhibited by statutes, rules, or regulations which unreasonably burden or restrict this movement."
Id., at 629. (emphasis added)
