Rumors are swirling that the Trump administration could end or greatly limit the DACA program to defer deportations of younger undocumented immigrants brought to the United States a decade ago. So what are the two sides of this widely debated argument?

A group of states, led by Texas, wants the Obama-era program to end. In 2012, the Department of Homeland Security issued deportation guidelines targeted at a specific group of people as part of the Deferred Action for Childhood Arrivals (or DACA) program. The group included undocumented people from other countries under the age of 31 who had been in the United States continuously since June 15, 2007; were under the age of 16 years old when they arrived; were in or had graduated from school or were honorably discharged veterans; and hadn’t broken the law in a significant way. About 800,000 people applied for the program, which deferred their potential deportation for two years and allowed them to work legally in the country, but it didn’t give them lawful citizenship status.

Texas and 25 other states sued the Obama administration in 2014 over a broader immigration directive that deferred deportations for the parents of those students and veterans. That group amounted to about 3.6 million additional people. The Obama administration also wanted to extend the DACA period to 2010.

A federal judge in Texas issued a national injunction to block the policies that extended the program to parents and people entering the United States between mid-2007 and 2010; the lawsuit didn’t deal directly with the DACA program. A federal appeals court added to that ruling to say that the policies exceeded President Obama’s policy-making authority. In June 2016, the Supreme Court, in a 4-4 vote, upheld the injunction in a one-line opinion.

On June 29, 2017, Texas Attorney General Ken Paxton told Attorney General Jeff Sessions that on behalf of 10 states, he was notifying the Justice Department that they would amend a suit against the administration if it didn’t change the 2012 DACA program by September 5, 2017.

“Courts blocked DAPA and Expanded DACA from going into effect, holding that the Executive Branch does not have the unilateral power to confer lawful presence and work authorization on unlawfully present aliens simply because the Executive chooses not to remove them,” Paxton argued. Paxton said the group would amend a lawsuit currently in the Southern District of Texas to include the 2012 DACA program, if executive action wasn’t taken by September 5, 2017 to phase it out.

The Paxton group didn’t demand an immediate end to the DACA program or the immediate deportation of participants. “This request does not require the Executive Branch to immediately rescind DACA or Expanded DACA permits that have already been issued,” Paxton said. But it wants new executive action taken to start the process of ending the DACA program.

And Paxton clearly thinks the group will win in court based on their prior success in blocking the other two Obama proposals. “For these same reasons that DAPA and Expanded DACA’s unilateral Executive Branch conferral of eligibility for lawful presence and work authorization was unlawful, the original June 15, 2012 DACA memorandum is also unlawful,” Paxton said.

If the Trump administration ends the program, the American Civil Liberties Union and others have vowed to pursue the issue. “[The] DACA is a lawful exercise of the enforcement discretion that Congress delegated to the executive branch in the Immigration and Nationality Act, which charges the executive with ‘the administration and enforcement’ of the country’s immigration laws,” the group argued in a statement released after Paxton’s announcement.

But how those challenges would emerge if the Trump Justice Department decides it can’t win in court is unclear. Ultimately, the issue could be decided by Congress if it passes the long-debated DREAM Act.

The Brookings Institute looked at some possible outcomes in late August. “Despite the demand to rescind the executive order and introduction of the DREAM Act, there may not be conclusive action from the federal executive or legislative branch anytime soon,” it concluded. The Brookings report concluded that if there is a short-term stalemate or delay over the 2012 DACA program, the states could expand or rescind tuition access for students in the DACA program as a way to influence policy.

Scott Bomboy is the editor in chief of the National Constitution Center.