Lower courts had blocked the policy, saying it was not supported by evidence and violated equal protection principles.
The Trump administration on Thursday asked the Supreme Court to let it start enforcing a ban on transgender troops serving in the military that has been blocked by lower courts.
The administration’s emergency application was the latest in a series of requests asking the justices to pause decisions by trial judges that prevent it from moving forward with the blitz of executive orders Mr. Trump has signed. The Supreme Court has allowed some initiatives to proceed and temporarily blocked others, issuing orders that have for the most part been technical and tentative.
The new case concerns an order issued on the first day of Mr. Trump’s second term. It revoked an executive order from President Joseph R. Biden Jr. that had let transgender service members serve openly.
A week later, Mr. Trump issued a second order saying that expressing what it called a false “gender identity” conflicts with a soldier’s commitment to an “honorable, truthful, and disciplined lifestyle, even in one’s personal life,” and that requiring others to recognize a “falsehood is not consistent with the humility and selflessness required of a service member.”
In February, the Defense Department implemented Mr. Trump’s order, issuing a new policy requiring all transgender troops to be forced out of the military. According to the Defense Department, about 4,200 current service members, or about 0.2 percent of the military, are transgender.
Service members sued to block the policy, saying it ran afoul of the Constitution’s equal protection clause.