A paperwork error from six years ago is threatening to overshadow rulings in the high-profile case of Salvadoran national Kilmar Abrego Garcia, turning what began as a story about a botched deportation under President Donald Trump into a running test of how well federal courts understand the basic mechanics of immigration law.

At a hearing on Nov. 20 in Greenbelt, Maryland, U.S. District Judge Paula Xinis told lawyers she could not find a final order of removal in Abrego Garcia’s file, even though the government insists he was properly ordered removed years ago. “You can’t fake it till you make it,” she said, according to Politico’s account of the hearing. “You have to have the order…memorialized somewhere, and I don’t have it.”