A new study indicates that mainstream economic news coverage tends to be biased in favor of Democratic presidents. The findings, which appear in the journal American Politics Research, provide evidence that the media is more charitable to Democrats than Republicans.

“Trust in the mainstream media has been on the decline for decades. It has fallen most among supporters of the Republican Party, partially in response to a constant drumbeat of complaints about a biased press from conservative elites. This is a serious problem. Trust in the mainstream news is essential for the health of a democracy, now more than ever. If there is something to these allegations, we need to address it,” said study author Eric Merkley, a Ph.D. candidate at the University of British Columbia.

“Complaints by conservative elites that the mainstream media is biased are typically dismissed as faux-outrage, while beliefs among rank-and-file Republicans to that effect are written off as evidence these citizens are being duped by their leaders. I wasn’t so sure, and academic research on this question is very much mixed. I thought it would be an important and challenging empirical problem to tackle.”

Merkley used automated content analysis software to evaluate the tone of 400,000 news articles related to unemployment and inflation. The articles were published between 1985 and 2013 by 23 high-circulating American newspapers and the Associated Press. (Editorials and opinion pieces were excluded.)

Merkley examined news articles about unemployment and inflation because both have objective metrics of performance.

He found that the tone of economic news coverage was more positive during Democratic presidencies, even after controlling for the economic performance.

“Journalists broadly lean to the political left and this has become increasingly true over time. These findings suggest there is a real possibility that journalists subtly frame news content in ways that serve their partisan interests,” Merkley told PsyPost.

“The key word is subtly. This study provides no evidence that mainstream media deliberately manufacturers false or misleading content to harm Republican presidents. Rather, the findings are consistent with confirmation bias. Journalists appropriately reduce tone in economic news in response to worsening economic conditions under Republican presidents, but are problematically more charitable during Democratic administrations.”

“This shouldn’t be a huge surprise. Being objective and impartial is darn near impossible for journalists and all citizens when our cognitive hard-wiring is oriented towards supporting our social group identities when we see and interpret information in the political world.”

All research includes some limitations, and the current study is no exception.

“The findings of any single study need to be interpreted within the larger assortment of literature that exists on a question. The reality is that there has been a large amount of work published on this topic and the findings have been very mixed. This isn’t the only word or the last word on this question,” Merkley said.

For example, another study published in 2016 found that most media outlets “present topics in a largely nonpartisan manner” — with the exception of overtly partisan outlets like Daily Kos and Breitbart News. But that study measured bias in a substantially different way and analyzed political news in general.

“My findings only apply to economic news content. It is possible that patterns of bias vary across broader issue types,” Merkley explained. “Perhaps the news media is biased against Republicans on economic issues because journalists expect performance to be poor compared to Democratic administrations (which is true on average). The pattern of bias may go against Democrats on different issues. For instance, maybe Democratic administrations will be at a disadvantage in crime reporting. More work should be done on this issue.”

“The method I use here is also meant to apply to strict performance issues where the public is in general agreement about what outcomes are good or bad (i.e. higher unemployment = bad). There are a lot of advantages to using performance issues, but they are only a subset of all the issues out there. A different approach needs to be taken on what we call directional issues where there is value-based disagreement among citizens about what policy outcomes are good or bad.”

“There is also a possibility that media bias has increased over time as journalist preferences have moved left and the Republican Party has moved sharply to the right. My methodology cannot address this question, but I certainly think it is worth exploring,” Merkley added.

“It is also important to note that this work does not address the growing conservative echo chamber, such as Fox News, Breitbart, Town Hall, etc. There is no doubt in my mind that patterns of coverage would look very different in these outlets. My focus in this research is in mainstream news outlets.”