1) First ammendment: Anyone can lie, ok? And, any speech has consequences.
2) THE "COMMONS" / spectrum / FCC: Anyone that uses part of the shared spectrum (broadcasters) & when calling a program "news"1, must be unbiased, factful, truthful, or at least show "both sides2" to issues*
1Fox News, in Florida, in court, proved that they were in fact entertainment, NOT news, so they could feel free to broadcast outright lies, factual untruths.
But of course, "both sides" is a fallacy to most real issues that have many more sides.
Those wiggle room *'s proved wide enough over time to lead to where we are today.