The U.S. Fifth Circuit Court of Appeals will hear opposing oral arguments from representatives of the federal government and of 26 states in New Orleans Friday on the implementation of President Barack Obama’s execution action to shield millions of undocumented immigrants from deportation. The two sides have been locked in a legal battle since December 2014, when the Texas-led state coalition challenged Obama’s orders as unconstitutional.

The two sides will argue for and against Obama’s “Deferred Action for Parents of Americans” and “Deferred Action for Childhood Arrivals” programs – key aspects of his order last November to shield as many as five million undocumented immigrants who met certain criteria from deportation, the Los Angeles Times reported. A panel of three judges, two of whom are regarded as conservatives, will preside over the hearing, in a case that many suspect the U.S. Supreme Court will eventually decide.

The states’ representatives have argued Obama’s attempt to enact nationwide immigration reform without legislative approval violated states’ rights under the Constitution. The Justice Department asserted the states have no legal basis on which to contest Obama’s actions. Representatives from each side will have one hour and 20 minutes to make their arguments, not including interruptions from the panel of judges.

U.S. District Court Judge Andrew Hanen issued an injunction in February which indefinitely blocked Obama’s executive orders. Hanen declined to remove the injunction in March until Justice Department representatives could explain how certain aspects of the program moved forward despite the court-ordered block.

In May, the Court of Appeals declined the Justice Department’s emergency request to lift Hanen’s injunction. The three-judge panel ruled the Obama administration failed to prove delays would damage the program and declined to limit the injunction only to the 26 states participating in the federal lawsuit, the New York Times reported.