President Donald Trump’s declaration of a national emergency earlier this month to build a wall on the U.S. border with Mexico has spurred a flurry of objections: Sixteen states have filed a federal lawsuit; dozens of former national security officials signed a statement saying there is no factual basis for it; and the U.S. House is scheduled to vote today on a resolution to block it.

This battle’s outcome is far from certain—Will the Senate Republicans who’ve voiced misgivings stand against the president? What happens if Trump vetoes a rare show of solidarity from Congress? Maryland Today checked in with Irwin Morris, professor and chair of the UMD Department of Government and Politics, to dial back the rhetoric and clarify what’s at stake.

  • The declaration itself isn’t unusual: Since the passage of the National Emergencies Act in 1976, presidents have declared national emergencies dozens of times, with some still in effect, such as blocking assets and financial transactions with countries like Iran, Libya and Sudan. What makes this situation different, Morris said, is the president using a declaration to achieve a goal after being explicitly denied by Congress.
     
  • States may not have standing: While the constitutional authority of the president to use money for a wall after Congress has already appropriated it elsewhere is “the broad substantive question” in play, Morris said it’s no guarantee a court case turns on that question. Since some of the states in the lawsuit, including Maryland, are not on the border, it’s unclear if a court will even agree they have the standing to sue in the first place. “Then you wouldn’t even get to the fiscal policy issue,” Morris says. “It’s not even clear what the focal set of issues will be.”
     
  • The declaration could be overturned—if the votes are there: An added legal complexity is that Congress already has the power to pass a resolution, putting judges in a difficult position. “The court has traditionally been loath to make a ruling on what is broadly a political question,” Morris said. But since Congress is divided, it will be extremely difficult to pass a resolution with a veto-proof majority. “There is clearly a mechanism for responding to the president,” he said. “They just don’t have the votes.”
     
  • The past won’t predict the future: However the situation resolves itself, Morris said, it’s unlikely that the questions surrounding the limits of national emergency declarations—especially since there isn’t even a clear statutory definition of what one is—will be cleared up. “The relative exercise of power by Congress and the president is a living question,” he said. “There are no final answers.”