This explanation is from the FCC website:
As public trustees, broadcasters may not intentionally distort the news. The FCC has stated publicly that "rigging or slanting the news is a most heinous act against the public interest." The FCC may act to protect the public interest when it has received documented evidence, such as testimony from persons who have direct personal knowledge of an intentional falsification of the news. Without such documented evidence, the FCC generally cannot intervene.
The FCC cannot interfere with a broadcaster's selection and presentation of material for the news and/or its commentary. However, the FCC does regulate content in some narrow areas. Federal law prohibits or limits the broadcast of obscene, indecent or profane language as defined by U.S. courts. Also, the FCC may issue penalties for knowingly broadcasting false information.
It sounds like the monkey is on our back to provide the proof. Someone will have provide insider information to nail a MSM broadcaster.