More than just a failure of interviewing, what happened with the NBC host is really a symptom of a larger problem that has hampered the media’s ability to report on the 2016 election campaign and on Republican candidate Donald Trump in particular.

The event Wednesday night was “an embarrassment to journalism,” according to New York Times columnist Nick Kristof, while former Wall Street Journal editor Bill Grueskin called it “a master class in bad interviewing.”

This #NBCNewsForum feels like an embarrassment to journalism. It's about soundbites, not serious discussion of foreign policy.

— Nicholas Kristof (@NickKristof) September 8, 2016

What did Lauer do so badly? Critics said there were a number of things, including what some saw as a tendency to lob softballs to the Republican candidate while not letting Democratic candidate Hillary Clinton get a word in edgewise.

By far the biggest criticism of the NBC interviewer, however, was that he allowed Trump to claim that he was not in favor of the Iraq War, a claim the candidate has made repeatedly, and a claim that is demonstrably false. As in, there are multiple interviews with Trump in which he makes it clear he supported the war.

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Despite this, Lauer let the statement slide, and moved on to other questions, at which point media Twitter erupted in an avalanche of derision and criticism.

“Everyone, and I mean everyone, knew this would happen. And Matt Lauer didn’t have a followup planned?” asked New York Times columnist Paul Krugman. Although NBC (CMCSA) later posted an update on Twitter (TWTR) refuting Trump’s claim, most of those watching argued that Lauer should have done so during the interview—not waited until later.

Seriously — everyone, and I mean everyone, knew this would happen. And Matt Lauer didn't have a followup planned? https://t.co/mm5ufZKjEx

— Paul Krugman (@paulkrugman) September 8, 2016

Not everyone agreed that Lauer should have challenged Trump’s statement, however, which is where the larger journalistic problem comes into play.

Political talk-show host Chris Matthews, for example, said after the event that if Lauer had called Trump out for lying, that would be equivalent to expressing an opinion, and moderators are supposed to be neutral.

Fox News anchor Chris Wallace, who is going to be moderating one of the debates between Trump and Clinton, said something similar in an interview. Wallace said it’s not his job to question the factual accuracy of a candidate’s statement during such an event.

“I do not believe it’s my job to be a truth squad,” Wallace said. “It’s up to the other person to catch them on that.” In effect, the anchor argued a moderator’s main job is to keep the event running smoothly and make sure each candidate gets equal time.

After tonight's events, consider again Chris Wallace's statement that it is against his principles as debate moderator to call out untruths.

— Jay Rosen (@jayrosen_nyu) September 8, 2016

This controversy harkens back to one that emerged at the New York Times (NYT) in 2012, when the newspaper’s public editor questioned if journalists at the paper should be “truth vigilantes” when interviewing politicians. In other words, if they should point out obvious lies or simply report what a person said.

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The response from many journalists at the time was that, of course, reporters should challenge such statements when they are clearly false. What else is a journalist supposed to do?

Matthews’ viewpoint, however—that challenging a statement amounts to expressing an opinion—highlights an ongoing issue for journalists, which is that many mainstream news outlets continue to see their job as remaining scrupulously balanced and objective. When a candidate blatantly lies, that becomes a serious problem.

The New York Times has struggled with this, and continues to do so. In a recent memo to staff, the paper’s standards editor lectured employees about expressing opinions on Twitter or Facebook (FB)—and not just expressing opinions, but linking too much to one political side or the other.

“If you are linking to other sources, aim to reflect a diverse collection of viewpoints. Sharing a range of news, opinions or satire from others is usually fine. But consistently linking only to one side of a debate can leave the impression that you, too, are taking sides,” he wrote.

These two things—Lauer’s failure and the NYT’s banning of opinions—are two different expressions of the same principle, which is that journalism can only function if reporters never express an opinion or challenge an obvious lie. This is what NYU journalism professor Jay Rosen has often called “The View From Nowhere.”

That kind of principle makes sense when you’re dealing with a relatively normal political environment, in which most of the candidates stick to an unspoken agreement not to lie or simply make things up, or make outrageous statements that have no bearing on reality.

Trump, however, demonstrably and repeatedly breaches this principle, and that is part of what gives him so much power and influence—especially when the traditional media reports his statements verbatim without bothering to express any opinions about whether they are correct or not, or whether they even make sense.

There are signs that even the New York Times and CNN are doing less of this, and are trying to fact-check Trump’s statements in real time. But clearly we still have a long way to go. And that’s a problem the media as a whole deserves the blame for—not just Matt Lauer.