Immigration advocates are on edge as a lawsuit against the popular DACA program makes its way through the courts, adding uncertainty to the lives of more than half a million U.S. residents.

Deferred Action for Childhood Arrivals, as the program is formally known, has so far survived a litany of court challenges, but it is on the ropes amid a Texas-led lawsuit that challenges its legality.

On Thursday, a three-judge panel of the Fifth Circuit Court of Appeals heard arguments in that case, where the Justice Department argued against Texas District Judge Andrew Hanen’s earlier ruling that the program is illegal.

“Today, the 5th Circuit Court of Appeals heard a case challenging the legality of DACA, threatening the lives of the hundreds of thousands of Dreamers who rely on the program. These young people have grown up here, built their lives here, and contribute so much to our economy and communities,” said Rep. Sylvia Garcia (D-Texas) in a statement to The Hill.

For an hour, the three judges — appointees of former Presidents Reagan, George W. Bush and Obama — heard arguments, including the Justice Department’s contention that the states have no standing to sue because DACA has caused them no harm.

Hanen had found that the coalition of states led by Texas had standing and ruled in September of 2023 against the Biden administration’s revamp of DACA as a memorandum replacing Obama’s 2012 executive order.

In 2015, Hanen ruled against an expansion of DACA and a partner program, Deferred Action for Parents of Americans (DAPA), and in 2021 he ruled that DACA itself was unlawful.

That 2021 ruling was bounced back to Hanen after the Biden administration’s memorandum, which Hanen ruled illegal, maintaining an injunction that allows current DACA beneficiaries to remain in status while the courts process the issue.

Regardless of the Fifth Circuit’s decision, which could be months away, the case is likely to go to the Supreme Court.

After more than a decade of litigation, many DACA recipients and advocates are growing weary.

“We have known for years the heavy toll that living in limbo has had on tens of thousands of DACA recipients,” said League of United Latin American Citizens National President Roman Palomares in a statement. “From a human standpoint, it is a tragedy of our times to see how a nation built upon a historical tradition of immigrants has turned its back on men and women whose only crime was holding on to their mother or father’s hand as children. It is inconceivable how they have been treated.”

DACA registration numbers are likely to continue to dwindle from their high of more than 800,000 people, as beneficiaries find new statuses, leave the country, die or stop applying for renewal.

In March of 2023, United States Citizenship and Immigration Services reported 578,680 people enrolled in DACA. By September of that year, the number was 544,690.

As DACA recipients age, they are more likely to have U.S. citizen children, take out mortgages and other loans and progress in their careers.

Though advocates are supporting the Biden administration’s defense of DACA in the courts, most say legislation is the only realistic way forward for the program’s beneficiaries — and for those who would have enrolled if DACA hadn’t been kneecapped in the courts.

“As we face this legal challenge, it’s more important than ever to protect Dreamers and make sure we keep families together, not tear them apart,” Garcia said. “That’s why I’ll continue fighting to pass the American Dream and Promise Act, which would provide DACA recipients with a long-overdue pathway to citizenship. We must all come together now to ensure Dreamers have a stable future in the only country they’ve ever called home.”