US / US-Mexico border Report: Army Will Turn Strip of Border Land Into Base Officials say move will allow troops to detain trespassers on Roosevelt Reservation By Newser Editors and Wire Services Posted Apr 14, 2025 5:12 PM CDT Copied A member of the US Army 212 Infantry 2nd Brigade stands next to the US-Mexico border as part of Joint Task Force Southern Border Thursday, April 3, 2025, in Douglas, Arizona. (AP Photo/Ross D. Franklin) A long sliver of federal land along the US-Mexico border that President Trump is turning over to the Department of Defense would be controlled by the Army as part of a base, which could allow troops to detain any trespassers, including migrants, US officials speaking on condition of anonymity tell the AP. The transfer of that border zone to military control—and making it part of an Army installation—is an attempt by the Trump administration to get around a federal law that prohibits US troops from being used in domestic law enforcement on American soil. But if the troops are providing security for land that is part of an Army base, they can perform that function. However, at least one presidential powers expert says the move is likely to be challenged in the courts. The officials say the issue is still under review in the Pentagon, but even as any legal review goes on, the administration's intent is to have troops detain migrants at the border. The corridor, known as the Roosevelt Reservation, is a 60-foot-wide federal buffer zone that ribbons along the border from New Mexico to California, except where it encounters tribal or privately owned land. It had been run by the Interior Department until Trump directed control be transferred to the Defense Department in a presidential memo released Friday night. For the next 45 days, the Defense Department will test taking control of a section of the Roosevelt Reservation in New Mexico, one of the US officials says. During that period, the Army will put up additional fencing and signs warning people not to trespass. People not authorized to be in that area could be arrested by the Army's security forces, the officials say. Troops are prohibited from conducting civilian law enforcement on US soil under the Posse Comitatus Act. An exception known as the military purpose doctrine allows it in some cases—but would not apply here and would likely be challenged in the courts, according to Elizabeth Goitein, an expert on presidential emergency powers at the Brennan Center for Justice. That's because even though troops would be on land designated as an Army installation, they would have to prove that their primary mission there was not to conduct border security and law enforcement—and the whole point of Trump's order transferring the Roosevelt Reservation to the military's control is to secure the border, she says. (More US-Mexico border stories.) Report an error