The Senate Judiciary Committee’s top Democrat and Republican are pressing FBI Director Robert Mueller to provide a “more complete accounting” of how the Bureau obtained the phone records of reporters in 2004.

“While we commend you for personally apologizing to the newspapers on behalf of the FBI, and for personally bringing this matter to the committee’s attention, we expect to receive a more complete accounting of this violation of the Justice Department’s guidelines intended to protect privacy and journalists’ First Amendment rights,” Sens. Patrick Leahy (D-Vt.) and Arlen Specter (R-Pa.), the chairman and ranking member of the committee, wrote in a letter to Mueller.

The journalists targeted by the FBI were reporting on Islamic terrorism in Southeast Asia at the time their phone records were obtained. Agents were supposed to follow up with a subpoena from a U.S. attorney, but no subpoena was ever issued.

Mueller ended the FBI’s use of exigent letters in 2007.

The two senators said the news demonstrates the “pressing need” for a reporter shield law. Both are sponsors of the Free Flow of Information Act, which would recognize a legal privilege for journalists who have promised confidentiality to a source.