Since at least 2011, the FBI has adopted secret rules to spy on journalists who publish classified information and hunt down their anonymous sources.

The federal agency’s covert tactics were revealed in classified FBI documents published Thursday by The Intercept, the online site co-founded by Glenn Greenwald who won a Pulitzer Prize for his role in publicizing the classified documents leaked by NSA whistleblower Edward Snowden.

The “Domestic Investigations and Operations Guidelines” includes an update on the use of National Security Letters, a demand to secretly obtain a person’s private information. In this case: phone records.

The document spells out whose approval is needed when the FBI is seeking phone records of journalists or news organizations “to identify confidential news media sources.”

Normally, the FBI must get the nation’s top prosecutor, the Attorney General, to approve spying on journalists.

But the FBI can avoid that process by having its own general counsel approve it.

Trevor Timm, executive director of the Freedom of the Press Foundation, said he was surprised that these rules “explicitly give the FBI the go-ahead” to use this tactic against journalists — because it was once reserved for hunting down terrorists and spies.

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