If Fox News viewers watched CNN instead, would it make a difference?

The establishment of Fox News in the late 1990s forever changed both media and politics in America, transforming the formerly staid world of television news into the series of political shoutfests we know and love-hate today. More than a quarter-century after its founding, however, the question persists: Does watching Fox News actually change voters' minds?

It's worth noting that, in a famous study published 15 years ago, economists showed that exposure to Fox could have a measurable impact on elections. Comparing markets that had received Fox to those where it was not yet available, the study concluded that the presence of Fox News was good for a Republican gain of 0.4 to 0.7 percentage points between the 1996 and 2000 elections. It was a decidedly modest effect — but large enough to sway that super-close election.

It's a slightly different question how watching Fox affects someone's views of the day-to-day controversies of politics. One view is that Fox is such an echo chamber that it can't possibly be changing minds. Only committed conservatives, the theory goes, would bother to tune in to Sean Hannity or Tucker Carlson, so what difference could it make what they say?

A pretty big difference, as it turns out, according to a new study by political scientists David Broockman of the University of California, Berkeley and Joshua Kalla of Yale. The research offers a much more granular look at the impact of Fox on its viewers, thanks to reliance on a resource-intensive experiment, rather than the broad aggregates of that earlier paper.

Broockman and Kalla recruited a sample of regular Fox News viewers and paid a subset of them to watch CNN instead. (Compliance was enforced with some news quizzes, for which additional compensation was offered.) Then the treatment group of switchers and the control group of non-switchers took three waves of surveys about the news.

The results: Not only did CNN and Fox cover different things during the September 2020 survey period, but the audience of committed Fox viewers, which started the month with conservative predispositions, changed their minds on many issues.

Switchers were 5 percentage points more likely to believe that people suffer from long COVID, for example, and 6 points more likely to believe that many foreign countries did a better job than the U.S. of controlling the virus. They were 7 points more likely to support voting by mail. And they were 10 points less likely to believe that supporters of then-candidate Joe Biden were happy when police officers get shot, 11 points less likely to say it's more important for the president to focus on containing violent protesters than on the coronavirus, and 13 points less likely to agree that if Biden were elected, "we'll see many more police get shot by Black Lives Matter activists."

Still, these are reasonably large changes from a one-month experiment. And they occurred despite the long-term effort of then-President Donald Trump to discredit CNN and other mainstream media outlets.

What's more, only so much news occurs at any given time. One story that broke while the experiment was ongoing was Bob Woodward's revelation that Trump was aware early that the new virus was "deadly" — specifically, that it was much worse than the flu, contradicting the president's later public efforts to downplay the virus. Those in the treatment group were more likely to know about this, as well as the fact that Trump did not meet with the family of Jacob Blake, the victim of a police shooting in Wisconsin the month before.

Over a longer span of time, presumably, more stories ignored by Fox News would have piled up. And indeed one of the things that switchers changed their minds about was Fox News itself: They became more skeptical that Fox would cover a story that reflected poorly on Trump, even if it were true.

This mode of political influence, where partisan media can simply ignore stories that are inconvenient, is a potentially powerful challenge to democratic accountability. It's also probably not symmetrical. Even media outlets that skew liberal in their coverage generally don't shy away from covering the COVID death toll or the rise in inflation.

Of course, Democrats can't improve their standing with the public by paying Fox viewers to switch channels. But one lesson they can take from this experiment is that nobody is impossible to reach.

The left, by contrast, tends to stigmatize any engagement with right-wing media, as if fearing contamination through association. If it were true that this media is consumed exclusively by people who are totally impervious to dissonant information, boycotting the RWM might be a defensible strategy. But Broockman and Kalla's research indicates that information flows at the margin really do matter. Any opportunity to present new facts to people, and new arguments, is valuable.