Three appellate specialists working on special counsel Robert Mueller’s investigation into Russian interference in the 2016 election made their argument debuts Thursday, defending the criminal charges against former Trump campaign chairman Paul Manafort in Washington’s federal trial court.

As Manafort has fought against accusations anchored in Mueller’s investigation into Russian interference in the 2016 election, the task of arguing in court generally has fallen to just a few lawyers between the two sides: defense lawyer Kevin Downing for Manafort and, from the special counsel’s prosecution team, Andrew Weissmann and Greg Andres.