October 18, 2023

Political leadership and anti-scientific messaging

Do populist challenges to scientific recommendations lead citizens to adopt risky behavior?

Jair Bolsonaro, former president of Brazil, takes a selfie with a fan.

Source: Palácio do Planalto, CC BY 2.0

During the COVID-19 pandemic, national health authorities in many countries recommended that citizens wear masks and practice social distancing to stop the spread of the disease. But at the same time, a number of political leaders downplayed or contradicted such advice.

In a paper in the American Economic Journal: Economic Policy, authors Nicolás Ajzenman, Tiago Cavalcanti, and Daniel Da Mata showed that anti-scientific messaging in Brazil had a significant impact on how closely citizens followed COVID-19 guidelines.

Brazil’s former president, Jair Bolsonaro, was one of the world’s most prominent political critics of early policies aimed at slowing the spread of COVID-19. He publicly flouted recommendations and regularly dismissed the effects of the virus, calling it “just a little dose of flu” and a media “fantasy.”

This paper is about Brazil, but more generally, anti-scientific rhetoric is a common characteristic of many leaders. Anti-scientific behavior and anti-scientific rhetoric could have very important, consequential effects on a lot of outcomes that we really care about.

Nicolás Ajzenman 

Over the course of the pandemic, Bolsonaro issued a steady stream of populist, anti-establishment statements. But two episodes stood out to the researchers.

On March 15, 2020, Bolsonaro joined street protesters and conservative activists to demonstrate against the Congress and the Supreme Court of Brazil. Standing among the crowds, who were disregarding social distancing recommendations, the president took selfies and fist-bumped supporters. 

Then, on the evening of March 24, Bolsonaro reaffirmed the message from nine days earlier by delivering a national address that aired on every TV and radio station in the country. In that pronouncement, the president emphatically opposed COVID-19 precautions implemented by subnational governments, advised the country to return to normalcy, and minimized the pandemic’s effect with unscientific claims.

Anecdotal reports suggested that Bolsonaro supporters took the messages to heart.

“I was living in Brazil at the time, and it was pretty clear that some people were actively going out and trying to have normal lives as if it was some sort of a political statement,” Ajzenman told the AEA in an interview.

Using front page news, Google searches, and Tweets, the authors showed that these two events garnered significantly more attention than other statements and actions from Bolsonaro, making them good candidates for estimating the impact of anti-scientific rhetoric on the behavior of Brazilians.


Measures of attention on key dates
The chart below shows four measures of attention—newspaper coverage, Google searches, Twitter retweets, and Twitter likes—given to Bolsonaro's public events and pronouncements against social distancing measures.
Source: Ajzenman et al. (2023) 


To obtain estimates, the authors identified pro- and anti-Bolsonaro municipalities based on vote shares from the 2018 presidential election. They then compared results from a social distancing index based on mobile phone location data, as well as credit card expenses on nonessential in-store purchases, from before and after the two major events in which the president publicly challenged social distancing policies.

Compared to anti-Bolsonaro municipalities, pro-Bolsonaro municipalities were much less likely to maintain isolation and avoid nonessential shopping immediately after the demonstration on March 15. And after Bolsonaro’s pronouncement on March 24, the relative degree of social distancing continued to diverge.

Overall, the findings suggest a significant decrease in social distancing in pro-Bolsonaro municipalities compared to anti-Bolsonaro municipalities following the president’s most visible public dismissals of scientific recommendations.

The authors say their work offers strong empirical support for the claim that political rhetoric from leaders has a significant impact on the behavior of their supporters.

“This paper is about Brazil, but more generally, anti-scientific rhetoric is a common characteristic of many leaders,” Ajzenman said. “Anti-scientific behavior and anti-scientific rhetoric could have very important, consequential effects on a lot of outcomes that we really care about.”

More than Words: Leaders' Speech and Risky Behavior during a Pandemic appears in the August 2023 issue of the American Economic Journal: Economic Policy.