From left: Defense Secretary Pete Hegseth, U.S. Border Patrol Chief Michael Banks and United States Attorney for New Mexico Ryan Ellison stand along the National Defense Area along the New Mexico-Mexico border in a recent visit to tout recent arrests. Courtesy USAO
From left: Defense Secretary Pete Hegseth, U.S. Border Patrol Chief Michael Banks and United States Attorney for New Mexico Ryan Ellison stand along the National Defense Area along the New Mexico-Mexico border in a recent visit to tout recent arrests. Courtesy USAOcca

U.S. Sen. Martin Heinrich (D-N.M.) on Wednesday sent a letter to the United States Department of Defense, asking leaders for information on how they are operating a newly designated military zone along New Mexico’s border with Mexico and whom they might be arresting within it.

Last month, Defense Secretary Pete Hegseth and others touted the creation of a National Defense Area along New Mexico’s 170-mile border with Mexico. The new designation meant that land under Interior Department control effectively became part of a military base in Arizona and made trespass there a criminal offense punishable by up to a year in jail and a $100,000 fine.

According to a Source New Mexico analysis, the newly designated military base covers an area of 400 square miles, though Defense officials say the new criminal penalties do not apply to the state and private land within that area.

Still, Heinrich and groups including the American Civil Liberties Union have raised concerns about the new zone and whether it will have unintended consequences for American citizens or the state of New Mexico. Some New Mexico State Land Office land is within the 400-mile area. The end of the 3,100-mile Continental Divide Trail is also within the National Defense Area, Heinrich noted.

The newly designated National Defense Area is more than 400 square miles, excluding state and private land. It's the result of a land transfer from the Interior Department that effectively creates a military base in the area in red, empowering federal troops to detain and transfer individuals they arrest there to federal law enforcement for criminal charges. Patrick Lohmann/Source NM
The newly designated National Defense Area is more than 400 square miles, excluding state and private land. It's the result of a land transfer from the Interior Department that effectively creates a military base in the area in red, empowering federal troops to detain and transfer individuals they arrest there to federal law enforcement for criminal charges. Patrick Lohmann/Source NMcca

“I have deep concerns that the Trump Administration is bypassing due process for individuals who either intentionally or unintentionally enter this newly restricted area, including United States citizens who may be stopped and detained by U.S. Army soldiers for trespassing on an unmarked military base,” Heinrich wrote to Secretary Hegseth.

Defense officials have said the new military zone allows it to use more resources and crack down harder on illegal border crossings. Several hundred people have faced new criminal charges so far since late April, according to federal court records.

However, United States Attorney for New Mexico Ryan Ellison has had to defend the new process in court in response to a judge’s concerns over whether people being arrested had adequate warning that they could face criminal charges, among other legal considerations.

Heinrich’s letter included a dozen questions about practical and legal considerations about the new zone, though he said he understands the Defense Department’s “states interest in reducing migrant crossings at the border.”

Some of Heinrich’s questions include:

“Can the New Mexico State Land Office access state land within the NDA? Can lease or permit holders on state land within the NDA continue to utilize those state trust lands pursuant to those leases or permits?”
“How many mining claims are within the boundary of the NDA?”
“It has been reported that at least 300 individuals have been detained within the NDA area since the designation. How many of these individuals were U.S. citizens or were legally present in the United States?”
“Does the NDA limit road access to any private property within the boundaries of the NDA? If so, how is the department providing access to those private property owners?”

Heinrich ends the letter noting that the residents of southern New Mexico have “longstanding relationships with these lands.”

“As such, decisions that significantly alter their access or legal standing must be made transparently and with meaningful consultation. Further, it is of upmost importance that federal laws and the Constitution are upheld,” Heinrich wrote.

Source NM is an independent, nonprofit news organization that shines a light on governments, policies and public officials.