The FBI doesn't want the public to know more about how its agents pose as journalists during undercover investigations. But, in a federal court case, Justice Department lawyers ... acknowledged in a court filing that FBI agents who pretend to be journalists create a chilling effect, making it harder for real journalists to gain trust and cooperation from sources. The astonishing admission came as the FBI attempted to fend off litigation from Reporters Committee for Freedom of the Press, which has filed requests for documents under the Freedom of Information Act. The Reporters Committee's litigation involves documents related to an FBI undercover operation in which agents posed as documentary filmmakers from a fake company called Longbow Productions to investigate Nevada rancher Cliven Bundy and his supporters. In a motion filed July 23, Assistant U.S. Attorney Johnny H. Walker argued that providing FBI documents about the Bundy investigation and others in which a journalistic cover may have been used would not only disclose sensitive investigative techniques but also ... "would allow criminals to judge whether they should completely avoid any contacts with documentary film crews, rendering the investigative technique ineffective." The FBI has previously disclosed that agents have pretended to be news reporters to further investigations. But questions remain about how often such covers are used and what policies are in place to govern the deployment of fake reporters.