The U.S. Supreme Court will determine in 2016 the constitutionality of President Barack Obama’s recent executive action on immigration.

Obama’s 2014 Deferred Action for Parents of Americans program would allow up to 5 million illegal immigrants, parents of U.S. citizens or lawful permanent residents here for five years, to remain in the U.S. on work permits. They would not have legal status, but they would be exempt from deportation (thus the “deferred action” status).

26 states, all with Republican governors, have challenged the executive order on legal grounds. So far, a district court in Texas and the U.S. Court of Appeals for the Fifth District sided with the Republicans, and Obama’s Justice Department filed with the Supreme Court to reverse the decisions of the lower courts.

Texas not only argues the executive action violated federal law and the Constitution, it opposes having to spend millions to issue drivers licenses to half a million Texas parents that would be eligible. The Obama administration declared Texas would not be forced to do this.

The decisions of the lower court halted Obama’s plan. The president would have the remaining months of his term to implement the program if the Supreme Court sides with him in June.

Obama’s earlier and similar executive action on immigration has not been challenged. The 2012 Deferred Action for Childhood Arrivals protected children brought illegally to the U.S. Over 720,000 have thus far been shielded from deportation through the order. Obama’s 2016 order would also expand this program.

Obama wants to give the undocumented immigrants the opportunity to “come out of the shadows” and have access to legal work. The conservative states have successfully argued in the lower courts that access to legal work also gives illegal immigrants access to “Social Security, Medicare, tax credits, and unemployment benefits,” though of course through legal work the undocumented would also be paying into those systems.

The summer decision will arrive in the middle of the 2016 presidential race, which has already generated fierce debate over the solution to illegal immigration.

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