It's referred to as journalistic ethics. There's actually a code of ethics and some organizations, like the Associated Press, require it of their members (in my ol' journalism days, I won a few "ethics" awards).
The problem here is not journalism, nor news media, but companies that pose a section of their programs in the guise of news media. However, such groups do not actually hire journalists, and instead their employees are ex-bloggers and ex-radio commentators, the bulk such being spin doctors, not news providers.
When you pick up the National Enquirer, you know you're picking up a gossip magazine with rarely any facts or supporting evidence. Unfortunately television and radio have succeeded in putting up the trappings of journalistic legitimacy, through the use of copycat graphics, stage-craft, and delivery --- making their special effects, camera work, and staging look like that of "legitimate" news agencies. This serves to trick people into "thinking" they're watching, or listening to, news but are instead watching or listening to op-eds/blogs.
There is, at present, a pressing need by journalistic representatives and organizations to differentiate themselves from these "posers," but it's simply not easy to do. Presenting facts and evidence is just that, and can only realistically be presented in a few ways. Opinions, blogging, and propaganda, on the other hand, are unrestrained and can always attempt to mimic the trappings of real news and their respective agencies.
So, instead, ethical journalists and their respective agencies are tasked with not only providing facts and evidence, but educating the readers into being able to differentiate between facts and fakery. Such is the example of CNN, with real news and commentators pointing out faux news, or NBC, with real news and faux news so as to capture a larger audience, or FOX, with real local news channels and their faux national channel.
There is also one additional thing to clarify: faux news isn't necessarily fake or false news. More often it is insufficient presentation, or skewed presentation of facts. Such as saying, "an incredible 1.2 million people are unemployed, what a travesty!!!" rather than indicating that unemployment is actually down from three years ago.
And while catching "emotional appeal" is a good way to differentiate fact news from faux news, as I indicated earlier, faux news works at mimicking real news, so often you receive distorted information from a guy with a straight face, only to have a commentator from that same agency later quote the distortion and pose an "emotional appeal." I.e., propaganda posed, then utilzed in an op-ed. Very common, unfortunately.
