President Donald Trump with Defense Secretary Jim Mattis.

President Donald Trump with Defense Secretary Jim Mattis. Associated Press

White House Expands Border Troops’ Authorities, Raising Questions

The defense secretary insisted on Wednesday that he will not be arming troops with guns, or detaining migrants long-term.

In the two weeks since the midterm elections, the alleged threat from a caravan of Central American migrants traveling to the southern border has largely faded from the president’s Twitter feed.

A series of reports on Tuesday suggested that some of the 5,900 active duty troops deployed to the border in response to the caravan could begin re-deploying as soon as this week, firing speculation that the mission was being wound down now that the Nov. 6 elections have passed. Right now, it is scheduled to conclude by Dec. 15.

But questions continue to swirl around the deployment. The day before Washington largely shuts down for the long holiday weekend, Defense Secretary Jim Mattis appeared to suggest that the border mission, derided by critics in Congress and some former military brass as a political stunt designed to fire up President Trump’s base, could go on much longer.

The Defense Department on Tuesday provided its first official estimate of the cost of the deployment—$72 million to date—a number that Mattis said he is “confident” will rise. And he suggested the possibility of new missions and added troops.

“Some of those troops certainly will be [home by Dec. 15] because we can anticipate based on the number of miles of [concertina] wire...we know the rate we can do it over certain types of terrain,” Mattis told reporters at the Pentagon. But, he said, “Some troops may not be, or some new troops may be assigned to new missions.

“This is a dynamic situation.”

Then, late Tuesday night, the White House sent a memo to the Pentagon broadening the military’s authority to interact directly with migrants. Up until now, troops operating on the border have been unarmed and limited to performing auxiliary support functions, like laying concertina wire and transporting supplies. Their official mission is supporting U.S. Customs and Border Protection, or CBP, and officials have been clear that they will not engage directly with migrants. Broadly, U.S. troops operating on the border are restricted by the 19th-century Posse Comitatus Act, which requires an act of Congress if the president is to wield the U.S. military for domestic law enforcement purposes.

But the new authorization, signed by Chief of Staff John Kelly, allows the military to “perform those military protective activities that the Secretary of Defense determines are reasonably necessary” to protect border agents, including “a show or use of force (including lethal force, where necessary), crowd control, temporary detention and cursory search,” Military Times reported.

How the troops will wield force on the border has been a point of fierce controversy and uncertainty. Trump said he had directed troops to “consider it a rifle” if migrants throw rocks at them. Some former senior military leaders characterized the remark as an unlawful order, arguing that the president had effectively ordered the military to open fire on unarmed civilians—a war crime. (Other legal scholars of the use of force have said that those assessments are overblown, because rocks can constitute a potential deadly weapon and the rules for use of force already envision a rubric for the appropriate level of response).

Mattis said the memo directs him to determine what authorities troops may need to “back up” CBP, and said that he will act only in response to a request from the Department of Homeland Security, or DHS—the CBP’s parent agency. He downplayed the suggestion that the new authorization will lead to heavily armed troops on the border or long-term military detention, which could run afoul of the Posse Comitatus Act.

“We’ll look at, what does DHS need—I now have that authority,” Mattis said. But, he said, “There has been no call for any lethal force from DHS. There is no armed element going in. I will determine it based on what DHS asked for and a mission analysis.”

If troops do use force in support of CBP, Mattis said, it will be “unarmed MPs” with shields and batons, not guns.

“The rules have not changed,” he said, referring to the both the mission-specific rules for the use of force and the standing rules for the use of force, the law enforcement-like regulations that guide U.S. troops when they are operating within the United States.

If U.S. troops detain any migrants under the new authorities, Mattis said, “I would put it in terms of minutes.”

“If someone’s beating on a border patrolman and if we were in a position to have to have to do something about it, we could stop them from beating on them and take them over and deliver them to a border patrolman,” he said.

The expansion of authorities reignited questions about whether the border mission runs afoul of the Posse Comitatus Act, long considered a bedrock U.S. law.

There are a number of exceptions to Posse Comitatus. President Dwight Eisenhower famously relied upon some of those statutes when he signed an executive order authorizing the 101st Airborne Division to enforce the desegregation of the schools in Little Rock, Ark. in 1957; troops were armed with bayonets in that instance.

But it’s unclear that the new authorization implicates the law. For one thing, the text of the document has not been made public. But legally, there is a distinction between enforcing immigration laws—which would raise concerns under Posse Comitatus—and protecting CBP agents in any clashes with migrants.

“The one point I want to make again is we are not doing law enforcement,” Mattis said. “We do not have arrest authority. There is no arrest authority under Posse Comitatus for the U.S. federal troops—that can be done, but it has to be done in accordance with the law. That has not been done nor has it been anticipated.”

Charles Dunlap, a former deputy judge advocate general of the Air Force, said in an email to Defense One that the new authority doesn’t appear to be “a game-changer in terms of what that military is expected to do.”

“Essentially, it’s seems that it will provide explicit authority to protect CBP officers who may find themselves in physical jeopardy,” the retired two-star wrote. “I would not expect to see troops actually enforcing immigrations laws, and Secretary Mattis’ remarks today would seem to confirm the idea that the original mission of merely supporting the civilian CBP officers who are actually enforcing the law continues to remain intact.”

Mattis was more succinct.

“Relax. Don't worry about it, okay?"