BOB GARFIELD:  This is On the Media. I’m Bob Garfield.

BROOKE GLADSTONE:  And I'm Brooke Gladstone. Throughout the winter and into the beginning of spring, pundits kept saying that once Trump’s rhetorical excesses were exposed as mere trumpery by the media, his support would drop off. Well?

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MALE CORRESPONDENT:  Donald Trump decisively wins the Indiana primary and Senator Ted Cruz drops out of the race, making Trump now the presumptive Republican nominee.

FEMALE CORRESPONDENT:  So we now know, yes, Donald Trump is the presumptive Republican nominee. I’m not even sure we have to use “presumptive” anymore.

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BROOKE GLADSTONE:  Trump won the primaries decisively, as the pundits were proved decisively wrong about the public turning on Trump once his lies were exposed. Brendan Nyhan, assistant professor of government at Dartmouth College, has long researched the question of political lies. And it turns out demonstrable, undeniable truth rarely changes people’s minds.

BRENDAN NYHAN:  At least for the people who have political views that might lead them to want to hold a particular belief, it can be very hard. When my co-author Jason Reifler and I exposed experimental participants to a mock news article that had corrected information in it, it could sometimes provoke them into counter-arguing that claim. And that seemed to make them more likely to indicate that they believed in the misperception, rather than less likely, as we’d hoped. And that's what so many fact checkers and so many journalists have struggled to overcome.

BROOKE GLADSTONE:  Why is that? Why do people resist factual information?

BRENDAN NYHAN:  It’s hard for all of us to admit that we’re wrong. It, it can be very uncomfortable, especially when what we’re admitting we’re wrong about implicates some aspect of our identity or worldview. Politics is, in some ways, the most important way that we express those values, and so, it's especially hard for us to admit that we’re wrong because it might say something about us or what we’d like to believe that we don't really want to hear or acknowledge.

BROOKE GLADSTONE:  I think William James once said that if they cannot deny the information away or attack the person bringing the information sufficiently to kill the information, then they will adjust their worldview only enough to include that information, leaving as much of it intact as they possibly can.

BRENDAN NYHAN:  We’ve seen that with the fallout from the fact- checking of Donald Trump’s claim to have seen thousands of people celebrating after September 11^th in the United States. Trump supporters, many of them have fallen back on auxiliary claims that don't actually back up what Trump said. They say things like, well, there were people celebrating in the Middle East or, there might have been this story I heard about a dozen people here or there, as people, you know, struggle in any way they can to find some kernel of validity in this totally bogus claim that no one can support or back up.

BROOKE GLADSTONE:  One technique is to attack the messenger and especially when the messenger are the media bringing evidence to the table, and it's probably because the media are such ripe targets, especially for conservatives.

BRENDAN NYHAN:  That's right. In the Republican primary, if the choice is who do you believe, Donald Trump or the mainstream media, a lot of voters would say Donald Trump.

BROOKE GLADSTONE:  Does fact-checking ever have an impact on public opinion?

BRENDAN NYHAN:  I think so. You know, Trump is kind of a perfect storm for fact-checking, in the sense that he’s totally indifferent to truth. But there's lots of other cases when fact-checkers can make a difference. When you get to less controversial politicians or issues that aren’t as polarizing as September 11th or immigration, I think fact-checkers have a better opportunity to reach people who can be more open minded. Trump is the exception. I've done research where we found that reminding legislators that they could be fact-checked seemed to make them more careful in the statements that they make.

BROOKE GLADSTONE:  Tell me about the wrong way to fact-check and the right way. I remember we've discussed that if you use the word “not” it tends to drop out. So you can't refute the lie that the president was born in Africa by saying the president was not born in Africa because after a few hours or a few days people will forget the “not” and they’ll just remember the assertion. So do not repeat the falsehood in your correction, right?

BRENDAN NYHAN:  That's right. As human beings, we have a tough time with negations. But there are ways that the media could be more effective. One is to seek out people who are speaking against their political interests and draw on them as sources. The worst-case scenario is the classic “he said, she said” where it says, a Republican says this and a Democrat says that, because that helps people sort themselves into competing tribes.

I think one of the mistakes we make in assessing the effects of fact-checking is to focus so heavily on the presidential level, where people's partisan allegiances are so strong, it’s going to be very difficult to change people's minds. They’re following that race more like fans of a sports team than they are dispassionate civic-minded voters, right? And that makes it really hard. The fact-checks can kind of function like a sports page of accuracy and then one side can say yea and the other side can say boo, but –

BROOKE GLADSTONE:  But you’re not going to switch your team because of it.

BRENDAN NYHAN:  That’s right, that’s right. Very rarely do we say, that ref is right, my team is cheating and I am no longer a fan.

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But as you move down the ladder to members of Congress, governors, city councilmen, state legislators, those people get much less coverage. And so, fact-checking, I think, can be more effective at those levels where people bring weaker predispositions to bear in thinking about whether they believe the fact-check or not.

BROOKE GLADSTONE:  Okay, Brendan, I get that. But do you find the more informed a person is, the less partisan they are in their beliefs?

BRENDAN NYHAN:  No, precisely the opposite. The people who know the most about politics are the most polarized.

BROOKE GLADSTONE:  So the facts don't matter all that much.

BRENDAN NYHAN:  They’re part of the equation in, in how we make our mind but a lot less than we’d like to believe. You know, the social allegiances we have, the values we have, those often matter a lot more. We can’t possibly understand everything that we’re really expected to in politics, and so we use these cues and shortcuts.

BROOKE GLADSTONE:  How important do you think truth and, most particularly, lies are in political campaigns and in American life?

BRENDAN NYHAN:  Politics isn’t just about the facts, but if you deviate from the facts for long enough, reality does kick in. Americans got a sense that the war in Iraq wasn't going very well and over time that began to filter into their interpretations of national politics, and all the PR tactics in the world couldn't save the Bush administration from the political consequences of the choices they had made there. It’s hard to maintain deception about the big issues, over time. And we actually have a pretty good record, I think, of calling out people who are the most outrageous and dishonest.

Trump stands as an anomaly historically in all sorts of ways, but one of them is he's breaching almost every modern campaign norm of what you can say as a politician. But I would expect that the patterns we’ve seen in the past will tend to persist. He’s unlikely to get away with this forever.

BROOKE GLADSTONE:  Brendan, thank you very much.

BRENDAN NYHAN:  My pleasure.

BROOKE GLADSTONE:  Brendan Nyhan is an assistant professor in the Department of Government at Dartmouth College.

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