As tensions rise with another election season, the ever-present rift between the Republican and Democratic parties becomes even more palpable. Discourse across party lines can be quite costly, sparking intense animosity that has killed many legislations and ruined many more family dinners.

With hot-button issues on the line, it may seem like partisan hostility is the inevitable product of a deep ideological rift, and that there's simply no avenue for reconciliation. However, while such a rift might explain tensions among legislators, tensions at the dinner table tell a different story. A small remark suggesting that a conversation is happening across the political aisle can often be enough to irreparably damage impressions, or even turn a trusted friend into a loathsome foe. If merely knowing that another person belongs to a different party than our own can have such a powerful impact, ideology may not be the only driver of U.S. political partisanship. Rather, our deeply ingrained tendency to sort ourselves and others according to group memberships may be distorting our judgment well before any specific ideological disputes could arise.

To examine this possibility, my collaborators and I tested the effect of party membership on people's judgments of emotional facial expressions, a nonverbal form of communication. We used pictures of people showing one of three emotions: anger, happiness, or surprise. We wanted to see if judgments of these facial expressions might change if viewers were told the people in the pictures belonged to the same (versus a different) political party than themselves. We also examined how participants judged the facial expressions in a neutral scenario, where participants were not told the party identity of the person in the picture.

Judgments of Surprise Shift More Easily than Judgments of Clear Expressions

We found that party membership of the people in the pictures only affected judgments of one of the three emotions: surprise. When participants were told the people in the pictures identified with the opponent party, participants judged those people's surprised faces as more negative—compared to when told the people identified with the same party as themselves, or even compared to when participants did not know the political party of the faces.

Notably, judgments of happy and angry faces were not affected by whether the people in the pictures shared the participants' party identification. This is most likely because, while happy and angry expressions have a relatively clear meaning, surprised facial expressions are more open to interpretation as they can have a positive (unexpected gift) or negative meaning (witnessing a robbery). Judgments of surprised expressions are more malleable to the influence of expectations or underlying biases. 

Judgments of Own-Party Emotion Were No Different from Judgments of Unknown-Party Emotion

Notably,  judgments of surprised faces thought to belong to one's own party were no different from judgments of surprised faces with an unknown party identity. This suggests that, while believing that the person in the picture belongs to the other party caused judgments of surprise to shift in the negative direction, believing that the person belonged to one's own party did not shift judgments in the positive direction. In other words, there was not an added affinity for individuals in one's own group.   

These results suggested that partisan animosity in the U.S. may be more strongly driven by contempt for the opponent party, rather than by loyalty to one's own party.

In sum, without prompting them to think of any specific ideological issues, we were able to shift participants' judgments of surprised facial expressions by changing which party they thought the person belonged to. When participants believed the person in the picture belonged to a different political party, they judged that person's surprised facial expression as more negative.

Our findings could indicate a troubling possibility; within moments of initiating a cross-party interaction, preconceived biases may have already poisoned the well, distorting perception of the other party's thoughts and intentions, and undermining efforts at effective communication.

While completely overcoming impulses to form impressions based on labels is not easy, perhaps being aware of biases can help. For example, other research suggests that slowing down and practicing mindfulness can help to overcome a knee-jerk negativity in response to surprised faces. Even if the ideological divide remains vast, there's still the elusive hope that discourse could be a little less intolerant and a lot more tolerable.

For Further Reading

Basyouni, R., Harp, N. R., Haas, I. J., & Neta, M. (2022). Political identity biases Americans' judgments of outgroup emotion. Journal of Experimental Social Psychology103, 104392.

Iyengar, S., Sood, G., & Lelkes, Y. (2012). Affect, not ideology: Social identity perspective on polarization. Public Opinion Quarterly, 76(3), 405-431.

Harp, N. R., Freeman, J. B., & Neta, M. (2022). Mindfulness-based stress reduction triggers a long-term shift toward more positive appraisals of emotional ambiguity. Journal of Experimental Psychology: General.


Ruby Basyouni is a PhD student at the University of California, Los Angeles. Her research examines how people decide who and what to pay attention to in their social environment.