The Fairness Doctrine was a policy of the United States Federal Communications Commission (FCC), introduced in 1949, that required the holders of broadcast licenses to both present controversial issues of public importance and to do so in a manner that was, in the Commission’s view, honest, equitable and balanced. The FCC eliminated the Doctrine in 1987, and in August 2011 the FCC formally removed the language that implemented the Doctrine.^[1]

https://en.wikipedia.org/wiki/Fairness_Doctrine

The equal-time rule specifies that U.S. radio and television broadcast stations must provide an equivalent opportunity to any opposing political candidates who request it. This means, for example, that if a station gives one free minute to a candidate in prime time, it must do the same for another candidate who requests it. The equal-time rule was created because the FCC thought the stations could easily manipulate the outcome of elections by presenting just one point of view, and excluding other candidates. It should not be confused with the now-defunct Fairness Doctrine, which dealt with presenting balanced points of view on matters of public importance.

There are four exceptions to the equal-time rule. If the airing was within a documentary, bona fide news interview, scheduled newscast or an on-the-spot news event, the equal-time rule does not apply. Since 1983, political debates not hosted by the media station are considered “news events,” and as a result, are not subject to the rule. Consequently, these debates may include only major-party candidates without having to offer air time to minor-party or independent candidates. Talk shows and other regular news programming from syndicators, such as Entertainment Tonight, are also declared exempt from the rule by the FCC on a case-by-case basis. ^[1]

This rule originated in §18 of the Radio Act of 1927; it was later superseded by the Communications Act of 1934. A related provision, in §315(b), requires that broadcasters offer time to candidates at the same rate as their “most favored advertiser”.

http://en.wikipedia.org/wiki/Equal-time_rule