I thought it was part of the original broadcast rights grants to NBC & CBS that stipulated that certain periods of time be devoted to news programs, but I could

I thought it was part of the original broadcast rights grants to NBC & CBS that stipulated that certain periods of time be devoted to news programs, but I could be wrong. EDIT: Yeah, the Fairness Doctrine https://en.wikipedia.org/wiki/Fairness_Doctrine https://en.wikipedia.org/wiki/Fairness_Doctrine