The request to the high court by Solicitor General D. John Sauer arose from a federal judge's decision earlier this month that found Mr. Trump's removal of the three commissioners — Mary Boyle, Alexander Hoehn-Saric and Richard Trumka Jr. — was unlawful and blocked their terminations.

The court’s ruling could now mean that once a child born to noncitizen parents leaves certain states, they won’t be considered a U.S. citizen.