Who is John Sauer? Solicitor General headlines Supreme Court oral arguments over birthright citizenship after Donald Trump order

The U.S. Supreme Court has begun hearing arguments 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. President Trump is in attendance; he is the first sitting president to attend oral arguments at the nation’s highest court.

John Sauer

Solicitor General D. John Sauer began his arguments by noting that the citizenship clause "was adopted just after the Civil War to grant citizenship to the newly freed slaves and their children, whose allegiance to the United States had been established by generations of domicile here."

It did not, he said, “grant citizenship to the children of temporary visitors or illegal aliens who have no such allegiance.”

Sauer, representing the administration, opened the arguments by saying that "unrestricted birthright citizenship contradicts the practice ‌of the overwhelming majority of modern nations."

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.


What is Birthright Citizenship and why is there a debate?


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

President Trump's directive issued last year violated citizenship language in the U.S. Constitution's 14th Amendment as well as a federal law codifying birthright citizenship rights, the lower court found, acting in a class-action lawsuit by ​parents and children whose citizenship is threatened by the directive.

The 14th Amendment has long been interpreted as guaranteeing citizenship for babies born in the United States, with only narrow exceptions such as the children of foreign diplomats or members of an enemy occupying force.

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.

Some of the justices including conservative Chief Justice John Roberts grilled the ​Justice Department lawyer defending Trump's action. Trump, wearing a red tie and dark suit, was sitting in the front row of the public gallery of the ornate courtroom.

The justices were hearing the Trump administration's appeal of a lower court's decision that blocked his executive order directing U.S. agencies not to recognize the citizenship of children born in the United States if neither parent is an American citizen or legal permanent resident, also called a "green card" holder.