This critique of political journalism can be read as a warning on too easily assuming your own lack of bias:

Prohibited from joining in political struggles, dedicated to observing what is, regardless of whether it ought to be, the savvy believe that these [journalistic] disciplines afford them a special view of the arena, cured of excess sentiment. … The savvy don’t say: I have a better argument than you. … They say: I am closer to reality than you. And more mature.” …

Writing the news so that it lands somewhere near the “halfway point between the best and the worst that might be said about someone” is not a truthtelling impulse at all. …

“He said, she said” journalism means[:] There’s a public dispute. The dispute makes news. No real attempt is made to assess clashing truth claims in the story, even though they are in some sense the reason for the story. …

The power to place certain people, causes and ideas within the deviant sphere is one of the most ideological things journalists ever do. … Journalists maintain order by either keeping the deviant out of the news entirely or identifying it within the news frame as unacceptable, radical, or just plain impossible…  If you don’t think separation of church and state is such a good idea; if you do think a single payer system is the way to go,… chances are you will never find your views reflected in the news. It’s not that there’s a one-sided debate; there’s no debate. (more)

Of course as with most critiques of journalism, this would be better directed to journalists’ customers. It is readers who drive the industry, and they aren’t especially interested in what is true, relative to what is within acceptable bounds to say.