Could Trump’s attack on birthright citizenship find fertile ground at the Supreme Court?

After Ark, it was widely assumed that anyone born in the U.S. who didn’t meet one of the three exceptions had “birthright citizenship.”

But conservative scholars argue that Ark didn’t include an exception for parents who are in the country illegally or transients because the issue simply didn’t come up — and if it had, the court would have held that they don’t owe “allegiance” to the U.S. 

“Permanent resident aliens are a far cry from aliens illegally in the country,” said Hans von Spakovsky, a senior legal fellow at the Heritage Foundation who was a member of the Federal Election Commission and worked in the Justice Department’s civil rights division.

“Subject to the jurisdiction” in the 14th Amendment means subject to complete jurisdiction, he emphasized: “A German tourist is subject to our territorial jurisdiction — he can’t just rob a bank in Boston. But he’s not to subject to our complete jurisdiction; he can’t be called for jury duty and he can’t be drafted into the military.”

However, Gerard Magliocca, a law professor at Indiana University, disagreed. “‘Allegiance’ isn’t in the text; it’s a made-up concept,” he argued, and conservatives are “using it to mean something different from what jurisdiction would ordinarily mean.”

“Subject to the jurisdiction” is “just about whether you’re subject to the law,” he added. “The words are being used in their ordinary sense. There’s no secret 'Da Vinci Code' meaning behind them.”

Conservatives also point to the language in Ark about being “domiciled” here and suggest that there’s no citizenship if the parents don’t have a lawful U.S. domicile.

But Magliocca thinks that’s also a red herring. “Legal domicile wasn’t a concept back then. It just meant where you live. ‘Domicile’ only became relevant with modern tax law,” he said.

The Supreme Court has never held that a child of immigrants without permanent legal status — or temporary visitors — is a citizen, but it has come close. In 1982 it held that children of immigrants in the U.S. illegally were covered by the equal protection clause of the 14th Amendment, and in a footnote it analogized the equal protection clause to the citizenship clause. And in 1985 the court commented in passing that an immigrant without legal residence had a child “who, born in the United States, was a citizen of this country.”

Neither of those cases directly concerned the citizenship clause and the comments about citizenship have no precedential value. However, if the court were to uphold Trump’s executive order, it would have to overturn more than a century of common understanding and practice.

That’s happened before. In 2008 the Supreme Court found that the Second Amendment protected an individual’s right to own a gun, overturning a century of practice and common interpretation by focusing on the original language of a constitutional amendment and the understanding at the time it was adopted.

The birthright citizenship issue is “extremely similar,” said von Spakovsky. And the current justices have shown a willingness to overturn longstanding assumptions about other constitutional issues.

Nevertheless, even most conservative analysts are willing to admit that the Trump executive order is a long shot.

“I can 100% guarantee” that the court’s three liberals — Kagan, Sotomayor and Jackson — will vote against it, von Spakovsky said.

The justices most likely to uphold it are Thomas and Alito, according to Shapiro, because they care more about original meaning and less about practical consequences.

“Roberts and Kavanaugh were creatures of the executive branch before they joined the court,” Shapiro said, and “they’re generally solicitous of executive branch authority.” However, he thinks that they and Barrett have a more pragmatic bent. “They’ll wrestle with this. We’ve had birthright citizenship for a century or so. Is it too radical a departure without legislation?”

Von Spakovsky hesitated to make predictions about the chief justice. “I frankly just don’t know what Roberts would do with this case,” he said. “Sometimes he’s so concerned about the court not looking political that he arrives at a decision that ends up making it look political.”

It’s possible the justices could simply duck the constitutional issue. For instance, they could hold that, under the “major questions” doctrine, the executive branch can’t make a sweeping change to citizenship rules without Congress’ approval, said Magliocca.

The cases attacking the executive order have all been brought by states, not parents, and the justices could also conclude that the states don’t have standing, Magliocca added. “They might say, ‘Gee, if we don’t decide, some other president will revoke the executive order and then we don’t have to do anything.’”

If the court rules on the merits, Magliocca thinks that no more than one or two justices will support the executive order because there is “very strong practice and no strong originalist argument.”

Shapiro said, “More likely than not, the court won’t want to disturb the settled understanding of decades of practice and they’ll find some way to preserve the status quo.

“But,” he added, “I wouldn’t go to Vegas and put money on it.”