The 1969 case, red lion broadcasting company v. fcc, confirmed the fcc's regulation called

Fairness Doctrine--this doctrine requires radio and television to provide balanced and fair information for issues especially in the case of personal attacks and public opinion. 

In this case, Red Lion broadcasting argued this doctrine of the FCC violated the 1st Amendment right of free speech. The Warren Court sided with the FCC and stated the doctrine did not violate free speech.