The Supreme Court ruled Thursday that migrants standing at the U.S.-Mexico border but not yet on American soil have no legal right to be processed by U.S. immigration officials, clearing the way for the Trump administration to revive a border-management practice known as "metering." The decision in Mullin v. Al Otro Lado resolves a years-long legal dispute over what it means, under U.S. immigration law, to "arrive in the United States."
What Metering Means — and Why the Court Was Asked to Define It
Metering is the practice of limiting the number of asylum seekers allowed to enter a port of entry at any one time, turning away individuals who cannot be immediately processed and directing them to wait in Mexico until capacity opens up. Customs and Border Protection first used the practice in 2016 under the Obama administration to manage surges in traffic at busy crossing points. The first Trump administration later expanded it.
Under the policy, asylum seekers who lacked valid travel documents were required to wait outside U.S. territory until officers had bandwidth to receive them. Those with valid documents could enter at any time.
A federal judge overturned the policy during the Biden administration after the non-profit legal services organization Al Otro Lado — whose name means "the other side" in Spanish and which provides legal aid to migrants — argued that immigration law required agents to process all asylum seekers who presented at ports of entry.
How the Court Drew the Line
Writing for the majority, Justice Samuel Alito concluded that a migrant who attempts but fails to step onto U.S. soil has not, in the legal sense, arrived in the country. Alito quoted directly from the relevant statute, finding that arrival only occurs when a person crosses the border itself, not when they approach it.
During oral arguments, Alito illustrated the point by analogy: someone who walks to a front door and knocks has not arrived inside the house. The Court applied that same logic to the port of entry, rejecting Al Otro Lado's argument that immigration law compelled officers to admit anyone who showed up at the threshold.
What the Ruling Changes
The decision gives the Trump administration legal standing to resume metering without court interference. James Percival, the Department of Homeland Security's General Counsel, said the ruling confirmed that a non-citizen is not "in the United States" until he is, in fact, in the United States.
For migrants and their advocates, the ruling narrows the circumstances under which a person can claim asylum protections before physically entering U.S. territory. Al Otro Lado's legal challenge, which reached the nation's highest court, ultimately failed to persuade a majority that the law placed an affirmative duty on border agents to process every individual who arrived at a port of entry regardless of capacity.
The court's holding turns on a precise statutory question about geography, not a sweeping rewrite of asylum law — but its practical effect is to restore a tool the government has now used across three administrations.