Andrew Miller testified for about two hours after losing a months-long legal battle to have the subpoena thrown out. Although the Russia investigation is over, the grand jury that worked with Mueller still hears testimony in cases that are tied to the investigation. Mueller's team handed off several cases, including the one against Stone, to other federal prosecutors.
Prosecutors sought Miller's testimony as they built a case against Stone, who was charged earlier this year with lying to Congress about his efforts to alert the Trump campaign to WikiLeaks' plans to release damaging information on Hillary Clinton during the 2016 presidential campaign.
American intelligence agencies have concluded that WikiLeaks got the information from Russian agents. Stone has pleaded not guilty. Miller's attorney, Paul Kamenar, said his client "doesn't have any knowledge about what Roger Stone knew about WikiLeaks and Julian Assange."
Prosecutors' continued push for Miller's testimony and documents could signal they are not finished investigating Stone, who is scheduled to go on trial in November. Mueller officially concluded his Russia investigation when he issued his final report in March and has now left the Justice Department. Mueller found no criminal conspiracy between Donald Trump's presidential campaign and Russia, but left open the question of whether Trump acted in ways that were meant to obstruct the investigation.
Miller said he fought the subpoena for nearly a year because he is a "strong libertarian." "I believe that you've got to push back on our government when they're trying to demand to travel across the country to sit with them on a whim, miss work and miss your family," he said outside the courthouse.