A federal judge in Washington raised questions Monday about how prosecutors working with Special Counsel Robert Mueller III will be able to prove a key element of their case over Russian interference in the 2016 election: the alleged intent of 13 Russian nationals and three Moscow-linked firms to evade U.S. authorities tasked with rooting out foreign participation in the American political process.

U.S. District Judge Dabney Friedrich, confirmed in November 2017 to Washington’s federal district court, said it was “hard to see” how the alleged Russian influence campaign was intended to interfere with the operations of the U.S. government rather than simply “confusing voters.”