On April 1, the Supreme Court heard oral arguments for Trump v. Barbara—a case that could affect the constitutional understanding of birthright citizenship in the United States, depending on how the Court decides it.

The key question of this case is whether or not a presidential executive order is consistent with the Citizenship Clause of the 14th Amendment to the U.S. Constitution and 8 U.S.C. § 1401 (a). The order, issued by President Trump on the first day of his second term in office, denies citizenship to children born in the U.S. whose parents are unlawfully or temporarily present.

Dr. Brett Curry, a Professor in the Department of Political Science and International Studies at Georgia Southern, provided insight into the background of birthright citizenship in the U.S. and the case before the Supreme Court.

“The 14th Amendment was, in the immediate sense, geared toward reversing the Dred Scott decision, which, in 1857, basically said that Black Americans were not citizens,” Curry explains. “This [amendment] was designed to sort of supply or to correct that defect.”

The Citizenship Clause found at the beginning of the 14th Amendment reads in part, “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States…”

Historically, the only exceptions to the Citizenship Clause were children born to foreign diplomat parents, children of foreign occupying armies, children born on foreign ships in U.S. waters, and American Indians. These exceptions are not subject to the jurisdiction of the United States due to the protection of foreign governments or the governments of Indian territories, whose jurisdiction they are subject to.

However, there are currently no foreign occupying armies, as was the case in some territories occupied by British invaders in the early 19th century, so that exception does not affect anyone in the United States today. Additionally, the 1924 Indian Citizenship Act, signed by President Calvin Coolidge, extended birthright citizenship “to all non-citizen Indians born in the territorial limits of the United States,” abolishing that exception.

Advocate for the government, Solicitor General D. John Sauer, presented an argument that focused on those very important words: “subject to the jurisdiction thereof.” 

President Trump was in attendance, listening to the first half of the oral arguments, as his Solicitor General brought the case for the government, making Trump the first sitting U.S. president to make an appearance at the Supreme Court.

Sauer contended that undocumented immigrants and U.S.-born children of undocumented immigrants are not included under the Citizenship Clause because they are not “domiciled” in the United States and do not have allegiance to the U.S. However, the parameters for domiciliation can be subjective, making it unclear how the government would seek to define or prove whether an undocumented person is or is not domiciled in the United States.

Justice Amy Coney Barrett raised this point to Sauer in her questioning, “How would you adjudicate these cases? You’re not going to know at the time of birth for some people whether they have the intent to stay or not, including U.S. citizens, by the way.”

Much of the questioning by the justices concerned precedent. The most significant precedent on birthright citizenship comes from the decision in United States v. Wong Kim Ark, which also makes several references to the word “domicil[e].”

The case involved Wong, a young man born in San Francisco to Chinese-citizen parents, and the question of whether he would be a citizen under the Citizenship Clause. The decision states that Wong was a U.S. citizen upon birth per the 14th Amendment because his parents were not “employed in any diplomatic or official capacity under the Emperor of China,” and had “a permanent domicil[e] and residence in the United States.”

Solicitor General Sauer argued, however, that in the case of modern illegal immigration, a different approach is required when interpreting the Citizenship Clause. “We’re in a new world now,” Sauer said.

“Well, it’s a new world. It’s the same Constitution,” responded Chief Justice John Roberts.

The Advocate for the respondents was Cecillia Wang, National Legal Director for the American Civil Liberties Union (ACLU). Wang argued that undocumented immigrants do not fall under any historical exception to the Citizenship Clause, and that the language of the 14th Amendment created “a closed set of exceptions to an otherwise universal rule.”

Wang maintained that denying citizenship to U.S.-born children of undocumented immigrants would be unconstitutional, as it would exempt a group from the Citizenship Clause that was never intended to be excluded.

“It would be contrary to the central purpose of the 14th Amendment Citizenship Clause to admit new exceptions,” said Wang. “The entire history of the Citizenship Clause is driven by the notion that we don’t want to have any other exceptions.”

Though it appears unlikely after the arguments, the case could have considerable ramifications if the Supreme Court upheld President Trump’s executive order.

Justice Sonia Sotomayor raised questions about what might happen should the Court rule with the government, specifically citing the potential for future presidents or congresses to “unnaturalize” people born in the U.S. to undocumented parents.

While much of the debate and the oral arguments before the Supreme Court surround the constitutionality of birthright citizenship, is there a way the Court could decide this case without ruling on the Constitution?

“The other thing that [the Court] could do is that in the early 1950s, there was the Immigration and Nationality Act, which effectively has much of the same language as the 14th Amendment,” explained Dr. Curry. “One of the off ramps that the justices could potentially take would be that they could say that ‘we’re not getting to the constitutional question. We are simply going to look at the statute that Congress passed and read that Congress seems to make clear that [the Immigration and Nationality Act] is simply talking about birthright citizenship.’”

Justice Kavanaugh himself mentioned this during his questioning of Wang.

“[The Supreme Court’s] usual practice, as you’re well aware, of course, is to resolve things on statutory grounds and not to do a constitutional ground,” Kavanaugh said.

Wang responded, saying, “[the ACLU] obviously [has] these two paths to a win here. We’re happy to win on either or both of them.”

The oral arguments for the case represent one of several more steps the Supreme Court will undergo before a final decision is made. The Court is expected to hand down its decision in late June or early July, before the end of its 2025-2026 term.