The Democrats asked the FBI to investigate whether authorities were previously aware of Yang's activities, to what extent she has interacted with Trump and how she was invited to a Super Bowl party at his West Palm Beach country club, among other matters. Signing on to the letter were House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., House intelligence committee chairman Adam Schiff, D-Calif., and Sens. Mark Warner of Virginia and Dianne Feinstein of California, the top Democrats on the Senate intelligence and Judiciary panels.