New study reveals correlation between Trump's repeated falsehoods and public misperceptions

New research published in Public Opinion Quarterly reveals a correlation between the number of times President Donald Trump repeated falsehoods during his presidency and misperceptions among Republicans, and that the repetition effect was stronger on the beliefs of people who consume information primarily from right-leaning news outlets.

By the time President Trump left office, he had made an estimated 30,573 false claims, according to the Washington Post Fact Checker, which informed this study. Some of these claims were repeated dozens and hundreds of times in various news and social media outlets.

To understand whether and to what extent the repetition of Trump's falsehoods affected public misperceptions, researchers at Vanderbilt Peabody College of education and human development surveyed 754 U.S. participants on 150 of Trump's claims; 301 participants were registered Republicans and 453 were Democrats or not affiliated with either party.

The survey did not reveal that the claims were made by Trump or how many claims were true or false. After completing truth ratings on all claims, participants completed optional questions about their demographic backgrounds as well as news and social media consumption.

The researchers found that repetition of Trump's false claims correlated with belief in the claims among Republicans but not Democrats; in fact, increased repetition of the claims correlated with a decrease in Democrats' misperceptions. These findings build on prior research on the "illusory truth effect," which contends that repetition increases belief in both true and false statements.

The type of media consumed may explain the partisan asymmetry in belief of Trump's claims, as the authors write, "Republicans may consume news media that amplifies these false claims, while Democrats may consume media that ignores or outright rejects them. Thus, repeated falsehoods by Trump may increase belief regardless of whether a Republican or Democrat sees it, but because news outlets' coverage of Trump's falsehoods varied, Republicans were more likely to see these false claims."

"We believe that the news media plays an important role in mediating the relation between what politicians say and what the public hears. Democrats and Republicans tend to listen to different media outlets and so were more or less likely to hear what Trump said and whether it was false," said Lisa Fazio, associate professor of psychology and human development and senior author on the paper.

In particular, the repetition effect was strongest among participants who predominantly watched Fox News, especially among Republicans. In addition, claims repeated mostly through X, the company formerly named Twitter, were more likely to increase belief for both Republicans and Democrats, "possibly because such claims gained broad coverage through, for instance, cable news," the authors write.

"These findings highlight the ways that prominent politicians may be able to shape public opinion, and they highlight the need for more to be done to curb the spread of misinformation in contexts like social media," said Raunak Pillai, the study's first author and a psychology doctoral student in Fazio's Building Knowledge Lab.

Ultimately, the researchers say that the results of this study suggest that repeated false statements by politicians may play an important role in creating misperceptions among the public.