WASHINGTON (AP) — The U.S. Supreme Court is hearing arguments at 10 a.m. ET over the constitutionality of President Donald Trump’s order to end birthright citizenship for children born in the United States to someone in the country illegally or temporarily.

The birthright citizenship order, which Trump signed on Jan. 20, 2025, the first day of his second term, is part of his Republican administration’s broad immigration crackdown.

Trump plans to be in attendance. He will be the first sitting president to attend oral arguments at the nation’s highest court.

Every lower court to have considered the issue has found the order illegal and prevented it from taking effect. A definitive ruling by the nation’s highest court is expected by early summer.

Here’s the latest:

Arguments have begun

Sauer, Trump’s top Supreme Court lawyer, is at the lectern, defending the president’s birthright citizenship order. Trump is in the courtroom.

There’s one American territory where people are not citizens from birth

On American Samoa, an island cluster in the South Pacific roughly halfway between Hawaii and New Zealand, native-born children are considered “U.S. nationals” — a distinction that gives them certain rights and obligations while denying them others.

American Samoans are entitled to U.S. passports and can serve in the military. Men must register for the Selective Service. They can vote in local elections in American Samoa but cannot hold public office in the U.S. or participate in most U.S. elections.

Those who wish to become citizens can do so, but the process costs hundreds of dollars and can be cumbersome. In 2022, the Supreme Court rejected an appeal seeking to extend birthright citizenship to American Samoa.

An Alaska appeals court is weighing whether to dismiss criminal charges against an Alaska resident born in American Samoa after she was elected to a local school board.

Trump arrives at Supreme Court for arguments in birthright citizenship case

Crowds watched from the sidewalks as Trump’s motorcade drove along Constitution and Independence Avenues, passing the Washington Monument and the National Mall on the way to the court building.

All 9 justices were born in the U.S.

Justice Felix Frankfurter, a native of Austria, was the last of six justices who were born abroad. The current court is American from birth.

Still, the citizenship issue hits close to home for some justices.

Thomas and Ketanji Brown Jackson are descended from enslaved people who eventually had their citizenship established by the 14th Amendment.

Justice Sonia Sotomayor’s parents were born in Puerto Rico, where residents became citizens under a 1917 law enacted by Congress. The justice most closely tied to an immigrant is Alito, whose father was born in Italy.

Former, future and almost presidents have been to and served on Supreme Court

Way back in 1841, former President John Quincy Adams represented a shipload of African men and women who had been sold into slavery in the famous Amistad case.

Former President William Howard Taft became chief justice nearly eight years after leaving the White House in 1913. Charles Evans Hughes left the Supreme Court for a presidential run in 1912, which he nearly won, then returned to the court in 1930 as chief justice.

In 1966, Richard Nixon argued his only Supreme Court case, which he lost.

The states have taken sides

Twenty-four Democratic state attorneys general put out a statement Wednesday morning saying they’re “proud to lead the fight against this unlawful order.”

While Democratic attorneys general have sued the Trump administration scores of times, the plaintiffs in this case are represented by the American Civil Liberties Union and other civil rights groups.

The Democratic attorneys filed court papers supporting their position. Twenty-five of their Republican counterparts filed a friend-of-the-court brief backing the Trump administration.

The only state sitting this one out is New Hampshire.

If the court upholds Trump’s order, who would be affected?

More than 250,000 babies born in the U.S. each year would not be citizens, according to research from the Migration Policy Institute and Pennsylvania State University’s Population Research Institute.

The order would only apply going forward, the administration has said. But opponents have said a court ruling in Trump’s favor could pave the way for a later effort to take away citizenship from people who were born to parents who were not themselves U.S. citizens.

Trump’s last time at the court was a ceremonial visit in 2018

The president and first lady Melania Trump showed up for the court ritual marking the arrival of a new justice following the confirmations of Justice Neil Gorsuch in 2017 and Justice Brett Kavanaugh a year later.

The ceremony for Trump’s third appointee, Justice Amy Coney Barrett, was delayed a year because of the COVID-19 pandemic and Trump, who was no longer in office, did not attend.

True to form, a Trump appearance would break with longstanding norms

Traditionally the president has avoided attending arguments to maintain distance between the government branches — since the executive officer’s presence is seen by many as a way to pressure the independent court to rule in their favor.

Given the unusual nature of it all — Trump’s presence in the courtroom spotlights how high the stakes are for him, as the court’s decision will have massive consequences on his longstanding promise to crack down on immigration.

It’s not the first time Trump has considered showing up for a high court hearing

Last year, Trump said that he badly wanted to attend a hearing on whether he overstepped federal law with his sweeping tariffs, but he decided against it, saying it would have been a distraction.

Trump’s presence unlikely to sway the court, expert says

Adam Winkler, a constitutional law professor at UCLA, told the The Associated Press that Trump’s attending SCOTUS oral arguments signals how important the president views this case.

However, Trump’s presence “is unlikely to sway the justices,” Winkler said, adding that the SCOTUS justices “pride themselves in their independence, even if some agree with much of Trump’s agenda.”

The fanfare of Trump being in the courtroom will make for a different experience for the justices themselves, however, as “Trump’s presence will make the atmosphere a little bit more circus-like,” Winkler said.

Top Trump lawyer argues against ACLU’s legal director

Solicitor General D. John Sauer is making his ninth Supreme Court argument and second in as many weeks. Sauer’s biggest win to date was the presidential immunity decision that spared Trump from being tried for his effort to overturn the 2020 election.

Sauer was a Supreme Court law clerk to Justice Antonin Scalia early in his legal career.

ACLU legal director Cecillia Wang, the child of Chinese immigrants, is presenting her second argument to the Supreme Court. In the first Trump administration, a 5-4 conservative majority ruled against Wang’s clients in another immigration case.

Alito celebrates his 76th birthday on the bench

It’s not an April Fool’s joke. Alito was born this day in 1950. Only Thomas, who turns 78 in June, is older than Alito among the nine justices.

Justice Clarence Thomas goes first

In the post-pandemic era, the other justices allow the 77-year-old Thomas, the longest-serving member of the court, to pose a question or two before the free-for-all begins.

In a second round of questioning, the justices ask questions in order of seniority. Chief Justice John Roberts, whose center chair makes him the most senior, gets the first crack.

Arguments are likely to exceed the allotted hour

The justices have routinely gone beyond the allotted time since returning to the courtroom following the Covid-19 pandemic.

Livestream begins a few minutes after 10 a.m., Eastern time

A buzzer and the court marshal’s cry, “All rise,” signal the justices’ entrance from behind red curtains. The livestream won’t kick in for several minutes, until after the ceremonial swearing-in of lawyers to the Supreme Court bar.