Roger Ailes, left, and Bill O’Reilly at the Hollywood Reporter 35 Most Powerful People in Media event in 2012. (AP Images for The Hollywood Reporter)

Since 2015, according to a new Pew Research Center poll, Republicans’ attitudes toward colleges and universities have become much more negative. The poll found that the number of Republicans who believe colleges have a “positive impact on the way things are going in the country” dropped from 54 percent in 2015 to 36 percent in 2017. Meanwhile, Democrats’ approval held constant at 72 percent.

Has that affected our politics? Several commentators have been asking that question: Has the right’s declining trust in academics, scientists and other experts — call it “anti-intellectualism” — influenced opinions about politics?

That’s what my new research looks into. Drawing on more than 40 years of survey data, I found that the answer is yes. You can find the new anti-intellectualism in the way candidates and political movements scoff at experts and their evidence — something we can see in public attitudes like the refusal to acknowledge human-caused climate change and support for politicians like Donald Trump.

President Trump and many of his top aides have expressed skepticism about climate change, while others say human activity is to blame for global warming. So what's the administration's real position? (Peter Stevenson/The Washington Post)

A certain kind of populism distrusts intellectuals and experts

The historian Richard Hofstadter famously referred to Americans’ distrust and dislike of experts as a form of “anti-intellectualism.” Anti-intellectualism has been increasing in the United States since the mid-1990s, primarily among ideological conservatives, according to recent research.

Throughout U.S. history, politicians have attempted to capitalize on voters’ anti-intellectual attitudes. George Wallace, for example, frequently referred to college professors and judges as pointy-headed intellectuals during his third-party campaign for president in 1968.

More recently, Trump was regularly skeptical of and sometimes openly derisive toward experts a during  his 2016 presidential campaign. Brexit campaigners were similarly skeptical about European Union bureaucrats, even throwing Trump’s famous “You’re fired!” catchphrase at European economists.

How I did this research

Does such antagonism toward the experts win over the citizens who hold anti-intellectual attitudes? To answer this question, I analyzed four decades of survey data from two sources.

One is the General Social Survey (GSS), a representative sample of Americans that has been conducted roughly once every two years since 1972. I measured anti-intellectualism in this survey using a question that asked respondents whether they place a great deal, only some, or hardly any trust in the “scientific community.”

During the 1990s, conservatives started to distrust experts

From the early 1970s through early 1990s, I found little ideological divide on this question. In 1991, for example, 47 percent of liberals and 46 percent of conservatives expressed high levels of trust in the scientific community. By the mid-1990s, however, views began to diverge. In 2014, 53 percent of liberals and only 36 percent of conservatives held high levels of trust in the scientific community.

The second source is a four-wave national panel study collected during the 2016 general election by the University of Minnesota’s Center for the Study of Political Psychology (CSPP), via Survey Sampling International. I measured anti-intellectualism in this survey using a question developed by Eric Oliver and Wendy Rahn. They asked more than 3,500 respondents how much they agreed or disagreed with this statement: “I would rather place my trust in the opinions of ordinary people than the opinions of experts and intellectuals.”

Here, too, I found significant differences between liberals and conservatives. In 2016, liberals earned an average score of 2.14 on the 0 to 4 point scale — in which zero meant strongly disagreeing that the opinions of ordinary people should be trusted over experts, and four meant strongly agreeing with that statement — while conservatives averaged about 2.42. The difference between the groups is a statistically significant 9 percent.

In each dataset, I assess the relationship between anti-intellectualism and the public’s political opinions using regression modeling. These models control for several other factors that might influence respondents’ political attitudes, such as partisanship, education and other basic demographics.

Anti-intellectual Americans were more likely to prefer anti-expert politicians like Wallace or Trump

Respondents who were more anti-intellectual were more likely to support candidates who spoke skeptically about experts. In the 1972 GSS, approximately 22 percent of those who “hardly trusted” the scientific community were likely to vote for George Wallace in 1968, compared with only 12 percent of those who placed “a great deal” of trust in experts.

I found a similar pattern among those who supported or opposed Donald Trump. In the CSPP study, respondents rated Trump and Hillary Clinton on scales ranging from 0 (very negative feelings toward a candidate) to 100 (very positive feelings). The difference between these two scales is known as a “comparative candidate evaluation,” or CCE, which I scaled to range from 0 (favoring Clinton over Trump) to 1 (favoring Trump over Clinton).

In July, those who strongly felt that expert opinions were less trustworthy than ordinary people’s were more likely to prefer Trump, with an average 0.49 CCE rating; those who strongly disagreed that experts were less trustworthy than ordinary people were more likely to prefer Clinton, with a 0.44 CCE rating. That’s about a 5 percentage-point difference between groups — and it grew to about 8 points among those questioned in in October, with 0.51 and 0.43 CCE, respectively.

Does being wary of experts lead people to support Trump, or does supporting Trump lead people to be wary of experts? Because the CSPP data interviewed the same respondents a number of times over the course of the election, I was able to use more complex statistical procedures to investigate whether anti-intellectual attitudes increased support for Trump, or vice versa. I found that that anti-intellectual attitudes led voters to support Trump, and not the other way around.

Attacking science, experts and professors can help get politicians elected

Anti-intellectualism may influence how politicians campaign in upcoming election cycles. My research shows that politicians can successfully earn support by calling into question not only scientific consensus, but those who produce it. Attacking scientists, college professors and other experts can be a politically useful strategy for those hoping to win over the support of people who hold anti-intellectual attitudes.

And elections, of course, have consequences. If politicians who deride experts win political office, they may take action consistent with those views once elected. For example, Trump did dismiss EPA science advisers and pull out of the Paris climate agreement — which may increase global carbon emissions, and also help win support on the 2020 campaign trail.

Matt Motta is a PhD candidate at the University of Minnesota. Find him on Twitter @matt_motta.