But with the election over and Trump set to give way to President-elect Joe Biden next month, Flores said the court battles over Trump's signature promise could stretch well past next month's inauguration.
"I could foresee that there are going to be some significant legal battles between now and at least Jan. 20, and possibly further into 2021," he said. "It depends on how quickly and how decisively the Biden administration reacts to what's going on down here."
PREVIOUS REPORT: Federal officials celebrate 400 miles of border wall construction
Flores represents Zapata County and two South Texas landowners in a lawsuit challenging Trump's 2017 executive order mandating construction of a physical barrier on the border. It also challenges a series of environmental waivers issued in May aimed at fast-tracking almost 70 miles of barrier from Webb County to Zapata County.
The lawsuit alleges the administration violated the Fifth Amendment's due process clause, which provides for equal protection under the law. The executive order "creates a 2nd Class United States citizen at the southern border who can have their land seized wholesale based on racist and white nationalist motives," the lawsuit states.
During the campaign, Biden said his administration would not build another mile of barrier should he win, and his campaign website states that during his first 100 days in office, he will end the "so-called National Emergency" that Trump declared in order to divert Department of Defense money to help build the barrier.
SEE ALSO: Border fence built too close to Rio Grande, engineers say
Still, Flores worries that the border barrier may not be among Biden's immediate priorities, which could allow the Department of Homeland Security to continue moving forward until it gets new marching orders.
"The thing I am really concerned about is that as we head into the winter months, the pandemic is going to get worse," Flores said. "And on day one, he's going to have an economic crisis."
Jessica Bolter, a policy analyst with the Migration Policy Institute, said last month that Biden could immediately end Trump's emergency declaration, but it's unclear how that would affect ongoing construction projects and the money already dedicated to them.
"Ending the transfer of future funds doesn't mean in itself that wall construction stops," she said.
Meanwhile, the Trump administration shows no signs of slowing progress on one of his most high-profile campaign promises. A U.S. Customs and Border Protection online tracker of border wall construction indicates a 69-mile stretch of new barrier is under construction in Webb County, and another 52-mile project is in the "pre-construction" phase.
The government hasn't built anything on the land that's part of Flores' lawsuit; court documents show that last month the federal government was granted more time to file documents seeking to dismiss the lawsuit, which would allow the project to proceed. Flores said hearings are possible as late as next month.
What? From 2019: Mexican cheese wall going up at US-Mexico border
"It's all going to depend how aggressive the feds are in moving forward with the construction," he said. "I just don't know why they would spend all this money. I guess people feel like they're going to get fired by President Trump between now and Jan. 20, I don't know."
The video above is from October 2020, when federal officials celebrated 400 miles of the new border wall system under the Trump administration.
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