A new book by leading scholars of partisanship explores the recent consequences of political hostility, and how it does and doesn’t affect democratic functioning

Is partisan hostility damaging American democracy?

The short answer is yes: Political animosity, which scholars recognize as the defining feature of American politics this century, can degrade democratic functioning. But the question begs for a long answer: To see and face the implications of partisan hostility, we need a nuanced understanding of its effects and its boundaries.

A forthcoming book by some of the foremost scholars of polarization amasses empirical evidence of the consequences of political hostility in recent years, and offers a theory of when it affects political beliefs and behaviors.

Partisan Hostility and American Democracy: Explaining Political Divisions and When They Matter (University of Chicago Press: 2024) will be released June 12 from authors James N. Druckman, Samara Klar, Yanna Krupnikov, Matthew Levendusky, and John Barry Ryan.

Study after study has shown a striking rise in negative feelings Americans hold toward the opposing party– a concept scholars call affective polarization. Roughly 8 in 10 partisans report these negative feelings, according to Pew Research Center, and the majority use pejorative words– such as “hypocritical,” “closed-minded,” and “immoral” to describe their counterparts. While partisans have maintained stable attitudes toward their own party over time, their “ratings” of the other party have plummeted since 1980 and notably in the last decade. The authors cite New York Times columnist David Brooks’s taut summation– in the age of affective polarization, “we didn’t disagree more– we just hated each other more.”

“We find that partisanship does shape political beliefs and behaviors, but its effects are conditional, not constant,” said co-author Yanna Krupnikov, an affiliate of the Center for Political Studies at the University of Michigan Institute for Social Research and a professor in the Department of Communication and Media. “It seems most likely to guide beliefs on issues that don’t have direct personal consequences, and it’s most powerful when parties send strong, clear cues on an issue.”

The authors test that framework using panel survey data from a 21-month period spanning 2019, 2020, and 2021– three tumultuous years that occasioned the COVID-19 pandemic and vaccine distribution; the murder of George Floyd and subsequently the largest protest movement in US history; the 2020 election and January 6 insurrection; two impeachments, and a shift in the congressional majority.

The best data for measuring animosity over time, according to the authors, is the “feeling thermometer” in the American National Election Studies (ANES) survey, where respondents rate their feelings toward a party or issue on a 101-point scale, in which “50 degrees” is the neutral fulcrum between “warmer” or “colder” feelings. The authors use that measure in their own data  along with additional measures: trust questions, trait ratings– where respondents evaluate how well positive and negative traits describe each party– and “social distance measures,” where respondents rank their comfort level in situations like having their child marry someone from the other party.

They find the effects of political hostility are most concentrated in individuals with comparatively high animosity, who are a distinctive group in America– with particularly strong political identities and high levels of political engagement. These “high animus” partisans are more likely to take and act on party cues about where they “should” stand, and more likely to reject the possibility of their own party compromising. 

We can observe that animosity can fuel polarization on issues that might otherwise be informed by independent deliberation. In 1997, for example, Democrats and Republicans were equally likely to believe in climate change science; today, there’s a pronounced divergence that can only be explained by parties staking a claim on the issue, Krupnikov said.

The authors focus particularly on the case of politicization that drove the gap between Democrats and Republicans’ behavior during the COVID-19 pandemic. Political hostility is more likely to shape partisan evaluations of party leaders, they report, but the case of Dr. Anthony Fauci demonstrates how party cues can politicize specific targets. The authors also found the effects of COVID’s politicization on behaviors like vaccine or mask resistance diminished when actors confronted the personal stakes of the illness. To further understand these party signal dynamics and when they matter, the authors investigated the effect of animosity on policy positions in cases where issues are politicized by both parties, one party, and neither party.

“The advantage of our theory is its recognition that partisan divides are not inevitable and on many issues most people agree,” said John Barry Ryan, also an affiliate of the Center for Political Studies. “Overall, we see that animosity shapes decision-making by heightening the effects of party cues.”

The authors argue that while partisan hostility has degraded US politics—for example, politicizing previously non-political issues and undermining compromise—it is not in itself an existential threat. Political hostility has little effect on popular beliefs in fundamental norms, and it’s unlikely to directly lead to democratic breakdown or collapse, they say. They also find that overall, partisans do not strongly support undemocratic practices. 

Yet there is considerable cause for concern that partisan hostility may erode democracy over time. Political hostility can result in blind loyalty and decision-making based purely on team mindset– with worrying implications– and animosity can spiral because it has self-perpetuating effects.

“We find that animosity has clear, predictable effects on prioritizing party over other considerations, especially for issues that lack clear and immediate consequences to a person,” Ryan said. “It affects policy positions that make democratic functioning difficult– like our willingness to compromise, or our judgments of party leaders, and how we respond to the pandemic.”

“Political elites can politicize issues and can potentially seize on division in hopes of gaining support,” said Krupnikov. “There is often a focus on voter division, but the future of American democracy depends often on how politicians– more than ordinary voters– behave.”

This post was written by Tevah Platt, communications specialist for the Center for Political Studies.