Washington, D.C.-based Preston Burton of Poe & Burton is no stranger to high-profile legal work, having represented two admitted Russian spies and erstwhile White House intern Monica Lewinsky, among others. Now the former Orrick, Herrington & Sutcliffe partner has a new spy-related assignment: helping a secretive intelligence court decide whether the U.S. government can keep telephone records it’s collected in bulk.

In an order made public on Thursday, Foreign Intelligence Surveillance Court Judge Michael Mosman tapped Burton to weigh in, as a friend of the court, on the government’s request to hold on to the controversial telephone data.