Two starkly different legal views on President Donald Trump’s moves to find funding for construction of barriers at the U.S.-Mexico border, a signature promise of his presidential campaign, were laid bare Tuesday morning at the U.S. Court of Appeals for the Ninth Circuit.

To the plaintiffs, a group of states and border nonprofits who sued separately to block funding, the administration violated the Constitution’s Appropriations Clause when it reprogrammed military funds for border construction after being denied in the budget passed by Congress following a 35-day government shutdown.