When the FCC was created in the early days of radio, there was a lot of debate about how the concept of free speech (and freedom of the press) applied. Through trial and error, in same cases, and a lot of debate, the folllowing legal structure emerged:
1)the "airwaves" are public property and public forums. They can be licensed but not owned. Why this was done can bee best understood by looking at the similar rulings abut public waterways--because everyone uses them, private ownership of what has to be a public area simply does not make sense.
The FCC was given power to regulate the airwaves. The whole issue is complex, but I'll stick to jsut three points--they are themain ones relevant to your question.
>the FCC rules on what can be allowed. This is a very limited role--essentially, they can only enforce laws passed by Congress, and any of their rulings can be overturned by the courts. but they can rule that a statement (or image on TV--like the famous Timberlake/Jackson "wardrobbe malfunction" at the Super Bowl--exceeds the bounds of decency. That ruling stood--the courts choose to uphold it.
2) The FCC is charged with ensuring that no one--or even a few --parties control too much of the nation's airwaes. That is, when the system was set up, the idea was that licensing should be limited and spread out. That way, you could not have just a few people or corporations dictating what was said/seen in the broadcast media.
3)The FCC was also charged with-in and ONLY in areas affecting political speech--with ensuring that no one political group could dominate the airwaves. One example of how they did this was the "equal time rule" which required that (within reason) all political candidates in a race had to be given the opportunity to have their say. Not a guarantee--if a candidate didn't raise the money to pay for ads, that was his/her problem. But (again ONLY for political speech) they could not be denied ad time by media.
I didn't forget freedom of the press. That was simpler--a straight extension of the rules applying to print media, and can be summarized in one sen dance: the government is not allowed to censor--or pressure--the media. (Which makes the just revealed pressure over Iraq coverage by the bush administration illegal, BTW). Like anything, its not QUITE that simple. The press can't reveal classified information about an ongoing military operation, for instance. But the rule in alost all casses is tthe government keeps their mitts off the press.
Now--the Fairness Doctrine.
In the 1990s, the Republican Congress stripped the FCC of its power to restrict concentrations of media ownership. Now, a decade later, just six corporations (one not an American firm) control almost all our major media. In addition, the GOP stripped the FCC of much of their authority to guarantee access to all political voices.
The Fairness Doctrine restores the FCCs power to require that media (radio and TV stations) must allow dissenting voices time. The basic frame work is the same: candidate s are on their own in raising money. but if they can--the media has to allow them to buy air time within reason.
Why was this law passed? Because turned out that the people who set the rules up in the first place had known what they were doing. In many localities, right-wing radio and TV managers would sell ad time to conservatives--but not to anyone else. The public were the losers--they got to hear only the right-wing party line, and were denied the chance to hear dissenting voices.
The Fairness Doctrine simply restores the original regulatory structure. In a way, the GOP/neocons did us a favor--they proved, by their abuses, that the system we had in the first place worked. That's good to know--and we'll probably be able to set up a better system in the future, thanks to their efforts to destroy the old one.
A final point. There is nothing "sacred" about the Fairness Doctrine, or the original rules it is based on. The reality is that you have to have a balance. We want a diversity of opinions--its vital to democracy and preserving our freedom. At the same time, we want the state to poke their nose into such aeas as this as little as possible. The rules are there to strike that balance.
Why not just "let the market rule?" Because, as the right-wing proved--that does not work in this case. If market factors had been the only consideration, you'd have seen very few outlets barring dissenting voices from the airwaves, as actually occurred. You'd have seen some changes, bu tif the market alone wee at work, you'd have seen an ongoing mix of opinions and ideas on the air.
Bear in mind that economics is NOT the only criterion at stake here--and in America, civil liberty and civil rights are traditionally taken to be of greater importance--and for good reason.
The reality is that in ANY human endeavor, you get people who try to abuse the system. Nor all they all right-wing. The Fairness doctrine are here because you have to have rules, just like you have to have rules for traffic safety. Because some idiot, corrupt politician, or crook, will try to beat the system if you give them a chance. In this particular issue and time, most of the "bad guys" are on the right. There have been times in our history when the reverse was true--and probably will be again. The point of the rules is to make sure we don't let them run or ruin our lives-or our country.