This post has a great quote on the role of the journalist by Dan Froomkin:
"Journalists should strive for accuracy, and fairness. Objectivity is impossible, and is too often confused with balance. And the problem with balance is that we are not living in a balanced time. For instance, is it patently obvious that at this point in our history, the leading luminaries on one side of the American political spectrum are considerably less tethered to reality than those on the other side. Madly trying to split the difference, as so many of my mainstream-media colleagues feel impelled to do, does a disservice to the concept of the truth."
Brayton points out that while this is true, the journalist "should call out either side on an issue when they become untethered to reality.".