Political animosity exceeds racial hostility, new Stanford research shows

New Stanford research shows that Democrats and Republicans are increasingly polar opposites – their political biases spill over into their social lives. Along party lines and ideology, more than even race or religion, Americans are distrustful of those who are not politically similar.

Christos Georghiou / Shutterstock Dems vs. GOP

Political disagreements are harder for Americans to bridge than racial or religious differences, according to a study co-authored by Stanford political scientist Shanto Iyengar.

New Stanford research has found that Americans are increasingly divided along political party lines – and those sentiments are stronger than racial biases.

"We were particularly surprised at the extent to which party politics has become a litmus test for interpersonal relations. Marriage across party lines is extremely rare," said Shanto Iyengar, a Stanford political scientist and director of the Political Communication Laboratory.

The evidence demonstrates that hostile feelings for the opposing political party are ingrained or automatic in voters' minds, he wrote in a new research paper.

"The polarization of the American electorate has dramatically increased," said Iyengar, whose co-author was Sean Westwood, a post-doctoral researcher at Princeton University. "We show that the level of partisan animus in the American public exceeds racial hostility."

Why? It is largely due to a witches' brew of political candidates relying on negative campaigning and partisan news sources serving up vitriolic commentary, according to Iyengar, the Harry and Norman Chandler Professor of Communication. 

The widening split, he said, is no longer just the Democrats vs. Republicans, but liberals vs. conservatives.

Attitudes and perceptions

Using a variety of survey indicators, Iyengar and Westwood show that negative stereotypes of the other party have intensified and that political affiliation is now a relevant cue for non-political decisions.

Partisans are much more likely today to express reservations over the prospect of a son or daughter marrying across party lines, the study noted. Evidence from online dating sites demonstrates that even though people are far from transparent about their politics, ideology is nonetheless a powerful predictor of the dating decision. 

To find out whether partisan attitudes predict non-political behavior, Iyengar and Westwood examined how 1,000 people viewed the resumes of several high school seniors competing for scholarships. Some of the documents included racial cues – "president of the African American Student Association" – while others had political ones – "president of the Young Republicans."

Those findings showed that race mattered. African-American participants showed a preference for the African-American candidates 73 percent to 27 percent. Whites showed a modest preference for African-American candidates, as well, though by a significantly smaller margin.

However, partisanship made a much bigger impact than race on how people thought about others. Both Democrats and Republicans selected their in-party scholarship candidate about 80 percent of the time even when the candidate from the other party had stronger academic credentials.

Trust issues

In another study, the researchers asked 800 people to play a "trust" game, in which player 1 is given some money and told that she can give some, all, or none of it to player 2. The researchers found that race didn't matter – but party affiliation did. People gave significantly larger amounts when they were playing with someone who shared their party group identity.

Iyengar suggested that – unlike race, gender or other social divides where attitudes and behavior are constrained by social norms of civility and tolerance – there are no similar pressures to temper disapproval of political opponents. People feel free to say bad things about their political opponents, he said.

"If anything, the rhetoric and actions of political leaders demonstrate that hostility directed at the opposition is acceptable, even appropriate," Iyengar said. "While Republicans view fellow partisans as patriotic, well-informed and altruistic, Democrats are judged to exhibit precisely the opposite traits."

He said he believes that increasing political collegiality will require significant social interventions that enhance the political heterogeneity of neighborhoods and friendship groups. 

"What we need is greater personal contact between Republicans and Democrats," Iyengar said.

Shanto Iyengar, Political Science: (650) 723-5509, siyengar@stanford.edu

Clifton B. Parker, Stanford News Service: (650) 725-0224, cbparker@stanford.edu