President Donald Trump is using a bizarre legal loophole to allow the military to perform domestic law enforcement activity on U.S. soil, an escalation of his already ultra-aggressive immigration and border security policies.
The Trump administration declared last month that chunks of land directly alongside the U.S.-Mexico border are now actually long, thin military installations — and that soldiers guarding those bases can detain and search trespassers before handing them over to law enforcement.
The military is usually barred from carrying out civil law enforcement work due to the Posse Comitatus Act, which was signed in 1878. But the law does have exceptions — including something known as the “military purpose doctrine,” which allows military activity on U.S. soil as long as it primarily furthers military function. The idea behind Trump’s new guidance is that soldiers are protecting military installations from trespassers, not technically enforcing immigration law or guarding the border.
Last month, the president signed an executive order directing the Interior Department to cede control of land along the border — known as the “Roosevelt Reservation,” as it was set aside by then-President Theodore Roosevelt — to the Defense Department, which has since started patrolling parts of the territory as if it were a military installation and detaining those who “trespass” on it.
Dozens of people have already been detained in this area, and New Mexico’s top federal prosecutor has filed federal charges against them. The tactic recalls Texas Gov. Greg Abbott’s (R) “Operation Lone Star,” in which state National Guard soldiers were deputized under state emergency powers to aid in thousands of trespassing arrests of migrants — though those are state charges and not federal ones. Soldiers involved in that mission previously told HuffPost it was a mix of extreme political theater and dehumanizing violence against migrants.
Border experts and civil liberties advocates say the new federal strategy is yet another aspect of Trump’s aggressive seizures of power, particularly when it comes to sealing the border and pursuing “mass deportation” of immigrants.
“There’s a lot of human rights concerns around using the military, which is basically trained for war, versus using law enforcement that’s trained to do civilian enforcement,” said Vicki Gaubeca, associate director for U.S. immigration and border policy at Human Rights Watch.
The Trump administration, she added, seems to be “scouring the books to figure out a way to concentrate more power under the executive.”
A Meeting Of The Military And Border Patrol
The dramatic changes at the border have happened quickly.
Last month, Trump issued an executive order on “sealing the southern border” and “repelling invasions” in which he commanded that a 60-foot strip of land running parallel to the border be transferred from the Interior Department to the Department of Defense and made into a “military installation.” He instructed Defense Secretary Pete Hegseth to use the land “to address the emergency at the southern border,” including by “exclud[ing] persons from a military installation.”
Two new military installations have since been designated.
The first, announced in an April 21 military press release, covers the 170-mile stretch of the New Mexico-Mexico border and is known as the “New Mexico National Defense Area.” It’s now considered an extension of Fort Huachuca, which is nearly 100 miles away in Arizona.
The second was only announced Thursday, when the Defense Department put out a press release about the “El Paso National Defense Area,” or EPNDA.
“The new NDA comprises 2,000 acres of land, including the banks and bed of the Rio Grande River along the southern border from the American Dam in El Paso to Fort Hancock, Texas; approximately 63 miles,” a U.S. Northern Command spokesperson, Capt. May Morales, told HuffPost in a statement.
“The land was transferred from the International Boundary and Water Commission to the Department of the Army and is assigned to Fort Bliss, Texas.”
“The newly designated El Paso National Defense Area is not part of the original Department of the Interior Roosevelt Reservation, which ends in New Mexico and was recently transferred to the DoD for border operations,” an Interior Department spokesperson, J. Elizabeth Peace, added in a statement after this article was published.
Trump’s militarized use of the New Mexico border land is based on a 1907 proclamation from Roosevelt, who set aside the strip of land in California, Arizona and New Mexico “as a protection against the smuggling of goods” between Mexico and the United States. The new military installation does not include Native American reservations.
Even before the introduction of EPNDA, dozens of people had been detained under the new military authority and are now facing federal charges.
U.S. Attorney Ryan Ellison, the top federal prosecutor in New Mexico, on Thursday announced 82 new federal counts filed against individuals who “willfully” violated the New Mexico National Defense Area. The charges carry potential penalties of up to one year in prison, Ellison’s office said in a press release.
U.S. troops are “authorized to temporarily detain and transfer individuals to federal law enforcement for prosecution,” Ellison said, adding that he was working “hand in glove” with the military and border patrol. He even posted “handshake” emojis on X showing the bizarre new relationship:
The Tucson Sentinel has tracked down charging papers against at least 28 defendants who were arrested starting April 24. On top of the novel charges related to the military base, they’re also accused of entering the United States without authorization, a standard border enforcement charge.
“Joint Task Force Southern Border has not detained any unauthorized trespassers within the New Mexico National Defense Area,” Morales, the U.S. Northern Command spokesperson, said in her statement. It’s not clear which agency specifically made these initial arrests.
Trump used some Roosevelt Reservation land in his first term to build sections of border wall.
But the move to use the land for border militarization shows the new extremes to which he is willing to go in his second term, which has been marked by a series of so-called “emergency” declarations that have allowed Trump to seize more and more power.
Border Patrol agents are civilian law enforcement officers with border-specific training. Members of the military are not.
“I don’t think that would have even passed the laugh test during the first Trump administration,” said Adam Isaacson, director for defense oversight at the Washington Office on Latin America. “Can you imagine proposing that to [former Defense Secretary] James Mattis?”
A ‘Transparent Ruse’
Administration officials have repeatedly indicated that their goal in establishing the military installations is to enforce civilian immigration law.
“Since January, the department has stepped up efforts to curb illegal crossings,” read a military press release last week, which quoted Hegseth saying: “Any illegal [attempt] to enter that zone is entering a military base — a federally protected area. You will be detained. You will be interdicted by U.S. troops and border patrol working together.”
“If someone steps on there, they’re stepping on a military installation. Now they can be detained by the military,” Interior Secretary Doug Burgum told Fox News’ Brian Kilmeade earlier this week, referring to the New Mexico National Defense Area.
But legal experts say the border ploy appears to be a way for the administration to get around the law that keeps the military from engaging in domestic law enforcement.
The Brennan Center, a nonpartisan law and policy organization, called the move “a transparent ruse to evade the Posse Comitatus Act without congressional authorization.”
“The nominal justification for apprehending and detaining migrants who cross the border is protecting the installation. But the installation itself was created to apprehend and detain migrants, as well as to secure their removal,” the Brennan Center’s Elizabeth Goitein and Joseph Nunn wrote in an analysis published Wednesday.
“These civilian law enforcement activities are not ‘incidental’ — they are the reason for creating the installation. And apprehending migrants who ‘trespass’ on the installation is the primary way in which this law enforcement mission will be furthered.”
The new strategy is bizarre not only for its legal reasoning, but also practically: Unauthorized border crossings are already quite low thanks to Trump’s radical attack against asylum rights.
Taking After Texas
U.S. soldiers have been operating around the border for years — but not like this.
Thousands of National Guard soldiers, for example, have been part of a federal border mission since Trump’s first term, a deployment Joe Biden continued. But up until now, they have only been allowed to do support work, including building infrastructure and conducting surveillance, and they’ve never been directly involved with hands-on arrests of migrants.
A completely separate mission — on the state level, not federal — has seen Texas National Guard troops helping to arrest migrants, and it highlights some of the potential hazards with Trump’s new border scheme.
Since 2021, Texas Gov. Abbott has sent thousands of Texas National Guard soldiers to the border as part of “Operation Lone Star.” The program has also included state troopers, and has involved busing migrants around the country, especially to Democratic cities like New York and Chicago.
Abbott’s operation also previewed Trump’s current strategy: He deputized the soldiers to help enforce state law. In effect, this has involved soldiers actively directing migrants to cross at certain parts of the border, like private ranch land, where they can be arrested for violating state trespassing laws.
Thousands of migrants have been charged with state trespassing violations as part of the operation. Many have languished in state jails for months, simply for going where Texas soldiers told them to go.
Soldiers who have spoken to HuffPost about Operation Lone Star said it is largely political theater, featuring soldiers carrying long guns and dressing in camouflage, measures Border Patrol agents generally don’t use.
However, the state has also tasked soldiers with “deterring” border crossings, which involves shouting at migrants to turn back — and occasionally threatening them, harassing them and even carrying out violence against them, as HuffPost has reported. (The state claims “Operation Lone Star maintains comprehensive accountability and oversight for all Service Members.”)
Kristin Etter, director of policy and legal services at the Texas Immigration Law Council, said the new Roosevelt Reservation scheme is just one more area where Texas seems to have been a testing ground for the Trump administration.
“The overarching theme is that we just have a giant negative [public relations] campaign against immigrants,” Etter said. “So that people see immigrants as criminals, so that you can put them in handcuffs and jumpsuits, and then people don’t really care what you’re doing to them when you’re taking away due process.”