Paul wanted Mueller to follow up with the Bureau’s definition of a “reasonable expectation of privacy,” including examples of how it might be defined in training manuals or department memos.

Kelly responded today that “all FBI agents are trained on the Supreme Court’s interpretations of a reasonable expectation of privacy under the Fourth Amendment, and on the circumstances where the FBI would be required to seek a warrant during an investigation.”

He argued that three cases of manned aerial surveillance heard by the Supreme Court “held that aerial surveillance was not a search under the Fourth Amendment requiring a warrant because the areas observed were open to public view and, as a matter of law, there was no reasonable expectation of privacy.”

“The Fourth Amendment principles applicable to manned aerial surveillance discussed in these cases apply equally to UAVs,” Kelly continued. “…With respect to UAVs, there is no physical trespass involved in their use, and a warrant would not be required under this standard.”

Paul said the response wasn’t to his liking, but acknowledged that the FBI did respond to his questions.

“The FBI today responded to my questions on domestic use of surveillance drones by saying that they don’t necessarily need a warrant to deploy this technology. I disagree with this interpretation,” said Paul. “However, given the fact that they did respond to my concerns over drone use on U.S. soil, I have decided to release my hold on the pending FBI director nominee.”

Wyden, the sole Democrat to lend Paul a hand during his March filibuster of John Brennan’s nomination, said he voted “present” despite the “unfortunate fact that the FBI’s surveillance authorities have been famously abused in previous decades.”

“After reviewing the record of Mr. Comey’s confirmation hearing and meeting with him in person, his views on surveillance policy and law remain unclear to me. I sent Mr. Comey a letter asking for written responses to several important questions on surveillance, including whether he believes warrantless wire tapping is legal, and whether he would commit to explain how much evidence the FBI needs to track Americans using their cell phone location data,” Wyden said.

That included questions about “the NSA’s ongoing dragnet collections of Americans’ phone records” and whether Comey felt that had any impact on privacy rights.

“Mr. Comey could have answered most or all of these questions without disclosing any properly classified information, but the Justice Department informed me today that he will not be responding to any of them,” Wyden continued. “I hope that Mr. Comey will turn out to be a wise and appropriate choice to head the FBI but without more information about his views on these important questions, I cannot vote to approve his nomination at this time.”

In that letter, Peter J. Kadzik, principal deputy assistant attorney general, said Comey would work with senators if confirmed.

“Mr. Comey has not been informed about the details or value of any programs currently employed by intelligence agencies to protect our national security,” Kadzik wrote Wyden. “He has, however, pledged that, if confirmed, he will work to accommodate the needs of the relevant congressional oversight committees, consistent with the FBI’s law enforcement and national security responsibilities.”

“We hope that this information is helpful,” the DOJ official added.