Wyden asked Mueller if the FBI needs a court-ordered warrant, requiring law enforcement to show probable cause of a crime, or uses a less strict standard to conduct surveillance on U.S. residents. With some disagreements in U.S. courts about the appropriate standard, it depends on the circumstance, Mueller said.
The FBI will "see where the courts go," Mueller said.
"You have identified the exact reason why I am trying to get the answer," Wyden said. "There's no doubt we are going to watch what the courts do in the days ahead. The question is, what would be the rights of Americans while that is still being fleshed out?"
Sign up for CIO Asia eNewsletters.