WASHINGTON, DC – Following oral argument at the Supreme Court this morning in Trump v. Barbara, a case in which the Court is considering the constitutionality of President Trump’s executive order purporting to limit birthright citizenship to children who have at least one parent who is a citizen or is lawfully admitted for permanent residence, Constitutional Accountability Center (CAC) Senior Appellate Counsel Smita Ghosh issued the following reaction:

At the Court this morning, many justices appeared skeptical of the Trump Administration’s effort to withhold birthright citizenship from children of undocumented or temporarily present parents on the grounds that the Constitution, which grants citizenship to those “born in the United States and subject to the jurisdiction thereof,” exempts those whose parents lack “domicile” in or “allegiance” to the United States.

Operating on the assumption that the administration’s proposed rule was, in Justice Barrett’s words, “not textual,” given that the Constitution refers to neither “allegiance” nor “domicile,” much of the discussion surrounded the history of the Constitution’s Citizenship Clause and the relevance of United States v. Wong Kim Ark, an 1898 case in which the Supreme Court held that the Citizenship Clause granted citizenship to the children of Chinese immigrants.

Even justices appointed by President Trump pushed back against the administration’s citizenship rule. Justices Barrett and Gorsuch challenged the government’s insistence that the citizenship of an infant born in the United States would turn on their parent’s domicile, underscoring the frailty of the administration’s reliance on domicile. As Justice Barrett noted, the “foundlings”—or children born without known parents—were a recognized concept in common law when the Fourteenth Amendment was ratified, underscoring the irrelevance of parental domicile.

Indeed, the amicus brief CAC filed in the case on behalf of an ideologically diverse group of scholars explains that during the Amendment’s framing and ratification, Americans described the Fourteenth Amendment as constitutionalizing a rule in which everyone born in the United States and generally subject to American authority would acquire citizenship by birth, no matter the status of their parents. One newspaper specifically explained that the Amendment would render a “foundling” as much a citizen as “the chief magistrate of the nation.”

And while both the Solicitor General and Justice Alito emphasized that President Trump’s Executive Order could be understood to address a “new world”—a circumstance not envisioned by the Framers of the Fourteenth Amendment—Chief Justice Roberts underscored that this approach would be atextual, adding pithily that while it may be a new world, “it’s the same Constitution.”

All the justices seemed to recognize that, as the Chief Justice’s statement makes clear, a ruling in favor of the Trump administration would undermine a great deal of United States history and entail a re-writing of the Constitution.