Partisan media? Cable viewers shift attitudes after changing the channel

Millions of Americans count right-leaning Fox News as their primary source of information about politics and current events. A new working paper co-authored by Yale political scientist Joshua Kalla presents evidence of the influence such partisan media outlets wield over people’s attitudes on the major issues of the day.

For the study, Kalla and co-author David Broockman of the University of California-Berkeley, conducted an experiment in which they recruited a sample of regular Fox News viewers and paid a random subset of them to watch rival cable news network CNN from Aug. 31 through Sept. 25, 2020. They found that the people who switched to CNN for four weeks developed different views on a variety of issues, including President Donald Trump’s handling of the COVID-19 pandemic and the racial justice protests that followed the killing of George Floyd, than those who continued watching Fox News.

The researchers selected Fox News for the study, they said, because the incumbent president happened to be Republican.

Previous research has suggested that partisan media affects voting behavior, but it is unclear exactly how it influences people’s views. The experiment provided evidence that partisan media outlets, by filtering out unflattering or negative information about their preferred ideological side, weaken the electorate’s ability to evaluate the performance of elected leaders. It also found evidence that, by setting the news agenda through its coverage choices, partisan media strongly influences the issues its viewers deem most pressing.

“The people in our study are committed Republicans and active voters who liked Donald Trump and disliked CNN. Yet, being paid to watch CNN altered their views on several prominent issues,” said Kalla, an assistant professor of political science in the Faculty of Arts and Sciences. “This is concerning because it suggests that, by providing viewers a biased set of facts through its framing and coverage decisions, partisan media undermines our ability to hold elected officials accountable.”

The researchers randomly divided a sample of 763 regular Fox news viewers into a 304-person treatment group, in which individuals were paid $15 per hour to watch CNN, and a 459-member control group that was not incentivized to watch the news network. Members of the treatment group watched CNN for an average of 5.8 hours per week during the study period. The researchers enforced compliance through a series of quizzes on CNN’s primetime coverage that participants were paid $10 a pop to take.

They focused the study on Fox News because President Trump, a Republican, was the incumbent president heading into the 2020 election, Kalla explained. Future studies conducted with a Democratic incumbent in office should focus on regular viewers of more left-leaning cable news networks, such as CNN or MSNBC, he added.

The researchers performed a transcript analysis of the content of each networks’ primetime broadcasts, documenting significant differences in the issues and events they covered during the study period with Fox News far more likely to report facts favorable to Republicans and CNN likely to do the same concerning Democrats. For example, CNN devoted substantially more broadcast time than Fox News to the pandemic’s severity and Trump’s failure to control it. By contrast, Fox News coverage consistently downplayed the pandemic as a public health threat and emphasized Trump’s efforts to protect Americans from the virus, according to the study.

At the same time, their analysis found, Fox News focused its coverage on the racial unrest that gripped the United States in the summer of 2020, consistently indicating that Joe Biden and the Democratic Party supported the protestors’ tactics and demands. Both networks covered voting by mail but approached the issue from opposing perspectives with CNN describing it as largely secure and Fox News suggesting it was vulnerable to fraud.

Three waves of follow-up surveys captured the opinions of people who’d switched to CNN and those who continued watching Fox News, exposing significant differences between the two groups. For example, participants who watched CNN were 11 percentage points less likely than the Fox News viewers to believe that it is more important for the president to focus on violent protests than the COVID-19 pandemic. They were six points more likely to believe that many foreign countries were more effective than the United States at controlling the coronavirus. The switchers were six percentage points less likely to believe that then-candidate Joe Biden supported eliminating all funding for the police. They were seven percentage points more likely to support voting by mail and nine percentage points less likely to agree that mail-in voting would generate widespread fraud.

The people who switched to CNN became more negative in their appraisals of Trump, including his management of the pandemic, his intelligence, and his honesty, according to the study. Switching to CNN also made people more aware of bias in Fox News’ coverage. For example, the switchers were less likely to agree that “If Donald Trump did something bad, Fox News would discuss it.”

However, the study showed the people who watched CNN did not become more positive in their evaluations of Biden or change their partisan identifications. A final survey, conducted two months after the incentivized period, offered little evidence that participants had continued watching CNN regularly. Many of the effects of watching CNN on their views and attitudes dissipated over time, the study found.

“Our study shows that Fox News doesn’t simply reinforce beliefs that its viewers already hold, it also feeds them a biased set of facts that leaves them with a warped understanding of factual reality,” said Broockman, an associate professor of political science at UC-Berkeley. “That many of our participants’ attitudes shifted back to their preferred ideological perspective after they stopped watching CNN suggests that partisan media serves to replenish people’s partisan loyalties and political beliefs, giving it formidable power over our discourse.”

The full working paper is available online.