U.S. Attorney General Merrick Garland told Abbott in a letter Thursday that the governor’s executive order “violates federal law in numerous respects, and Texas cannot lawfully enforce the Executive Order against any federal official or private parties working with the United States.”

Garland said the Department of Justice “intends to pursue all appropriate legal remedies to ensure that Texas does not interfere with the functions of the federal government” if Abbott does not rescind the order.

On Wednesday, Abbott issued the order, allowing Texas Department of Public Safety troopers to reroute civilian vehicles back to their origin point or a port of entry, or seize the vehicles, if police suspect the driver is transporting migrants who are infected with the virus.

Abbott said in a statement that his order “will reduce the risk of COVID-19 exposure in our communities,” though the governor will not allow local government officials to issue mask mandates even as coronavirus infections are again increasing across the state.

Merrick’s legal threat to Abbott is the latest in an immigration battle between the Biden administration and Texas.

Earlier this summer, Abbott said the state would build a wall at the Texas-Mexico border. He has also threatened to pull the state licenses of Texas facilities contracted by the federal government to host migrant children. The Biden administration has threatened to take legal action against Texas if Abbott follows through on that plan, too.

Abbott responded to Garland’s letter saying it is the Biden administration’s fault for positive COVID-19 cases rising among migrants and that it “fundamentally misunderstands what is truly happening at the Texas-Mexico border.”

“In short, the Biden administration is jeopardizing the health and safety of Texans on a daily basis by refusing to follow the law,” Abbott said in a statement. “And it’s not just Texans; these irresponsible policies and actions by the Biden Administration are endangering the lives of many Americans as well as the unlawful immigrants themselves. I will take every available step consistent with the law to fulfill my duty to protect the health and safety of all Texans.”

Currently, the Biden administration is immediately turning back many migrants under Title 42, which allows agents to make migrants return to Mexico because of the risk of spreading COVID-19. This practice has been in place since the Trump administration.

Advocates say that Abbott’s most recent order would not only disrupt shelters who have been hosting migrants released by Border Patrol agents but would also invite troopers to racially profile people. They also said that this would impact volunteers who drive migrants to bus stops or airports.

Many of the migrants have attempted to enter the country through the Rio Grande Valley. Many of them have requested asylum and immigration officials have released some migrants pending the outcomes of their asylum cases.

Some migrants stay at shelters until friends or relatives send them money for a bus ride or plane ticket to their U.S. destination.

Kate Lincoln-Goldfinch, an immigration attorney in Austin, said on Wednesday the order could be legally challenged because “how would DPS accomplish this task without racial profiling?”

“If it is followed to the letter, it’s going to violate someone’s rights,” she said.

Dr. Michele Heisler, the medical director for Physicians for Human Rights, said on Thursday that Abbott’s order can actually put migrants more at risk of being exposed to the virus because if they’re not allowed to connect with their families across the country they could be held in detention centers where they may not be able to socially distance.

“Yesterday’s order by Gov. Abbott is motivated by xenophobia and not backed by any science,” she said. “This executive order directing state police to pull over, reroute–and even impound–vehicles in which migrants are traveling will not reduce COVID-19 exposure in the state.”

This article originally appeared in The Texas Tribune at https://www.texastribune.org/2021/07/29/greg-abbott-migrants-dps-joe-biden-merrick-garland/.

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