Power
People often discuss the "power of the press," but let's be clear: when they say that, they're not talking about the woman in big fuzzy mittens doing a live feature on how Miss Kravutz shovels her snow in rural Maine.
Then again, the adage isn't always completely false, either. Maybe reporting on Miss Kravutz's special two-handed-palm-reversal shoveling technique will encourage some viewer to try it out on the snow outside of his house. Maybe that, in turn, prevents an accident. It's an unlikely example, but follow the logic: when you report the news, you're bound to have some kind of impact.
Opinions are shaped not only by what's reported, but by how and how much of that comes through the reporter's script, body language, and delivery. Saying "George the Cat was flattened by a steamroller today," in a grim or sad voice makes it sound like George was some kind of beloved feline town hero.
Saying the same in a perky or excited tone makes it sound like George was some kind of deranged, feral beast, and that we can all rest a bit easier tonight knowing he's gone. Two totally different meanings from the same piece of reporting. Magic, right?
So while you can't really choose the news or lie about what's happening, you're still the gateway between current events and those seeking to learn about them. That position will always carry some form of power, which is probably why most journalists go through ethics training as part of their education. We just have to hope they paid attention.