The Justice Department warned officials in Texas on Thursday that the federal government will sue the state unless it removes border barriers it recently set up in the middle of the Rio Grande to repel migrants from entering the U.S.

In a letter to Texas Gov. Greg Abbott and the state's interim attorney general, two Justice Department lawyers said the floating barriers authorized by Abbott earlier this month violate federal law, threaten to impede the work of federal law enforcement and create "serious risks" to public safety and the environment.

"Texas's unauthorized construction of the floating barrier is a prima facie violation of the Rivers and Harbors Act. This floating barrier poses a risk to navigation, as well as public safety, in the Rio Grande River, and it presents humanitarian concerns," wrote Todd Kim, an assistant attorney general, and Jaime Esparza, the U.S. attorney for the Western District of Texas. CNN first reported the letter. 

The Justice Department officials gave Texas a chance to hold talks with the administration to prevent litigation and demanded a response by Monday. "If we do not receive a response by 2:00 P.M. Eastern Time on July 24, 2023, indicating your commitment to expeditiously remove the floating barrier and related structures, the United States intends to file legal action," they wrote.

In a statement on Twitter on Friday, Abbott appeared undeterred. "We will continue to deploy every strategy to protect Texans and Americans — and the migrants risking their lives," he wrote. "We will see you in court, Mr. President."

The river buoys have come under national scrutiny recently after a Texas state trooper raised internal concerns about the barriers diverting migrants, including children, into parts of the Rio Grande where they are more likely to drown. The internal complaint also raised other concerns about Texas' broader border initiative, known as Operation Lone Star. The trooper described migrants being cut by razor wire set by the state and directives to push families back into the Rio Grande.

The letter by the Justice Department said Texas needed to seek permission from the federal government before setting up the buoys, and that it had failed to do so. Because the barriers obstruct "navigable capacity" along the Rio Grande, the department argued, they violate the Rivers and Harbors Act.

A Biden administration official told CBS News the floating barriers have interfered with Border Patrol efforts to patrol the river and process migrants who reach U.S. soil. In one week, the official added, Border Patrol encountered dozens of injured or drowned migrants, including babies.

Once migrants are on the U.S. side of the border — which, in Texas, falls in the middle of the Rio Grande — federal law requires Border Patrol officials to process them and decide whether they should be deported, transferred to another agency, detained or released. The law also requires federal officials to review the asylum claims of those who ask for refuge. State officials are not authorized to enforce these laws.

Over the past two years, Abbott, a Republican, has engaged in a high-profile feud with President Biden, a Democrat, over how the federal government has handled a historic migration wave along the U.S.-Mexico border, where Border Patrol recorded an all-time high in apprehensions in 2022.

As part of his campaign to repudiate what he has decried as lax Biden administration border policies, Abbott has bused thousands of migrants to Democratic-led cities, ordered the arrest of migrant adults on state trespassing charges and deployed members of the Texas National Guard to set up razor wire along the banks of the Rio Grande.

Unlawful entries along the southern border in June plunged to the lowest level since the start of the Biden administration, defying predictions that the end of a pandemic-era order known as Title 42 would fuel a massive spike in unauthorized migration to the U.S. 

Biden administration officials have attributed the sharp reduction in illegal border crossings to its unprecedented efforts to expand opportunities for migrants to enter the U.S. with the government's permission, as well as its stricter asylum rules for those who don't apply for these programs.

"Governor Abbott's dangerous and unlawful actions are undermining our effective border enforcement plan and making it hard for CBP to do their jobs of securing the border," White House spokesperson Abdullah Hasan said in a statement. "The governor's actions are cruel and putting both migrants and border agents in danger."  

— Robert Legare contributed reporting.

Camilo Montoya-Galvez

Camilo Montoya-Galvez is the immigration reporter at CBS News. Based in Washington, he covers immigration policy and politics.

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