Journalists in the media filing center watch as Republican presidential candidates participate in the Houston debate in February, sponsored by CNN. (Richard Carson/Reuters)

Each week, In Theory takes on a big idea in the news and explores it from a range of perspectives. This week we’re talking about digital media ethics. Need a primer? Catch up here.

Jay Rosen teaches journalism at New York University and writes the blog PressThink. Follow him on Twitter: @jayrosen_nyu

Journalists commonly divide information from persuasion, as when they separate the “news” from the “opinion” section, or “reporters” from “columnists.” This is fine as far as it goes (and they get criticized harshly when they don’t honor this norm), but the distinction won’t help much in understanding why the 2016 campaign has been such an intellectual challenge for the media.

Everything that happens in election coverage is premised on a kind of opinion: that our votes should be based on reliable information about what the candidates intend to do if elected. Remove that assumption and the edifice crashes. But this is exactly what the candidacy of Donald Trump does. It upends the assumptions required for the traditional forms of campaign journalism even to make sense.

Take one of Trump’s most famous claims: that he will build a wall on the border with Mexico and get Mexico to pay for it. Is that a serious proposal? Should journalists review it as one? If they do examine it as a policy idea, are they helping us achieve greater clarity about the Trump candidacy (by taking a hard look at what he would do if elected), or are they distorting the Trump phenomenon by treating a parody of policy discussion, a kind of goof on the political class, as a genuine proposal?

“Mexico will pay for the wall” chips away at one of the foundations of campaign coverage: that running for president is serious business. If you take it seriously, you become the joke. If you don’t, then you let him get away with an absurdity. The fact that there’s no right answer should tell us something. Trump is crashing the system — violating norms and assumptions that were previously taken for granted because so far, everyone who had reached the point of consideration had obeyed them.

One of the newer parts of that system is fact-checking, but this is also a practice with a premise. The premise is that fact-checking will have some shaming effect on the kind of behavior it calls out. Notice I said “some.” While all candidates (including Hillary Clinton) will avoid inconvenient facts, make dubious claims or even lie at times if they think they can get away with it, they normally change behavior when a statement has been widely debunked. They may not admit they were wrong, but they will stop repeating the unsupportable claim, or alter it to make it more plausible. That’s what a “check” is supposed to be: it constrains a candidates’s power to distort the public dialogue.

Trump shatters this premise. As FactCheck.org put it: “He stands out not only for the sheer number of his factually false claims, but also for his brazen refusals to admit error when proven wrong.” Said Glenn Kessler, The Post’s Fact Checker columnist: “What’s unusual about Trump is he’s a leading candidate and he seems to have no interest in getting important things factually correct.”

Under conditions like these, fact-checking may still be worthwhile, but not because it has any shaming effect on the candidate. In fact, it could even be useful to Trump in whipping up resentment against the media, a key part of his appeal. My point is this: When the assumptions underneath a practice collapse, the ethics of that practice may shift as well.

Traditionally, journalists have called out untruths. Here they may have to explain how untruths are foundational to a candidacy. Traditionally, journalists have thought it “ethical” not to worry about the consequences of election coverage: as long as it was truthful, accurate and newsworthy, all was well. Here they may have to worry that their checking actions have no effect, and regroup around that discovery.

One of the assumptions of campaign coverage was that candidates would never use their huge platforms to spread malicious rumors and unreliable information for which they have no proof: Too risky, too ugly. Trump has crashed that premise too. When called out on his rumormongering, he just says: Hey, it’s out there already. For journalists, this changes the practice of giving the candidate a broadcast platform. Just by granting that platform you may be participating in a misinformation campaign. Are you sure you know what you’re doing?

Imagine a candidate who wants to increase public confusion about where he stands on things so that voters give up on trying to stay informed and instead vote with raw emotion. Under those conditions, does asking “Where do you stand, sir?” serve the goals of journalism, or does it enlist the interviewer in the candidate’s chaotic plan?

I know what you’re thinking, journalists: “What do you want us to do? Stop covering a major party candidate for president? That would be irresponsible.” True. But this reaction short-circuits intelligent debate. Beneath every common practice in election coverage there are premises about how candidates will behave. I want you to ask: Do these still apply? Trump isn’t behaving like a normal candidate; he’s acting like an unbound one. In response, journalists have to become less predictable themselves. They have to come up with novel responses. They have to do things they have never done. They may even have to shock us.

They may need to collaborate across news brands in ways they have never known. They may have to call Trump out with a forcefulness unseen before. They may have to risk the breakdown of decorum in interviews and endure excruciating awkwardness. Hardest of all, they will have to explain to the public that Trump is a special case, and the normal rules do not apply.

Other perspectives:

The debates gave Donald Trump the nomination, and it’s the media’s fault