Are conservatives or progressives more biased? New study finds it depends on who’s in power

A new study sheds light on how political power influences ideological prejudice in the United States, revealing that people’s ideological bias against opposing beliefs intensifies when their own party is not in power. The research analyzed data spanning nearly five decades, showing that conservatives are more prejudiced against progressives when Democrats hold power, and progressives exhibit stronger biases against conservatives when Republicans are in charge. Published in the Journal of Experimental Psychology: General, the study offers new insights into how ideological prejudices shift based on political circumstances.

The researchers behind the study — Johanna Woitzel from Ruhr University Bochum and Alex Koch from the University of Chicago — aimed to address an ongoing debate: is ideological prejudice inherently stronger among conservatives or progressives? This question has been contested for years, with some studies suggesting conservatives or progressive are generally more prejudiced, while others argue that ideological bias is a universal response to opposing viewpoints. Woitzel and Koch proposed a new angle: that political power dynamics might shape how strongly people hold prejudices against opposing ideologies.

To test this hypothesis, they used data from two main sources: the American National Election Studies (ANES) and the Agency–Beliefs–Communion (ABC) model studies. ANES provided an extensive longitudinal dataset, covering political attitudes from 1972 to 2021, while the ABC studies offered recent data from 2016 to 2021, focusing on people’s perceptions of various social groups based on ideological alignment.

The researchers pooled and reanalyzed 27 studies — 21 from ANES and six from the ABC model — each of which included information on people’s ideological self-identification, prejudicial feelings toward different groups, and the political environment at the time of data collection. ANES, with its nationally representative samples, measured ideological dissimilarity by asking participants to rate their attitudes toward various groups on a spectrum of “warmth” and “coldness,” which essentially indicated likability or dislikability. The ABC studies, on the other hand, captured ideological prejudice by asking participants to rate groups based on trustworthiness, likability, and morality.

In analyzing these data sources, the researchers identified the party in power during each period and created a political power index to account for which party controlled the presidency, vice presidency, Senate, and House of Representatives. This political power index varied from -0.5 (indicating complete Republican control) to +0.5 (indicating complete Democratic control). By integrating this index with the participants’ ideological scores and prejudice measures, the researchers could assess if and how shifts in political power influenced ideological prejudice.

The researchers found that changes in governmental power were closely tied to fluctuating patterns of ideological prejudice: conservatives displayed increased prejudice toward progressive groups during Democratic administrations, while progressives showed stronger bias against conservative groups during Republican-led administrations.

To complement these findings, the researchers conducted two new experiments. In the first experiment, 1,004 participants were recruited to rate a series of groups under conditions that varied both the measures of ideology (narrow vs. broad) and the form of prejudice assessed (feelings vs. thoughts). This design was intended to evaluate whether the measurement approach could influence the strength or direction of ideological prejudice. Participants rated their own ideological alignment on a scale from conservative to progressive and then completed assessments of prejudice toward groups with contrasting ideologies.

The results of this experiment indicated that measurement style (narrow political ideology vs. broader measures including lifestyle and religion) did not significantly alter the findings, reinforcing the robustness of the ideological prejudice effect.

The second experiment tested the impact of sample representativeness by comparing results from a nationally representative sample of 1,000 U.S. residents with a more accessible sample of 1,044 online workers recruited through Prolific Academic. Both groups rated their prejudicial feelings toward various groups identified in a pilot study as common ideological groups in U.S. society, including Democrats, Republicans, LGBTQ+ people, and religious groups. The results showed consistent levels of ideological prejudice in both samples, suggesting that the study’s findings were not influenced by sample characteristics.

To test for causality, the researchers conducted a third experiment that included an imagined political power scenario, asking 994 participants to envision either Democrats or Republicans holding complete control of the U.S. government. Participants then rated their prejudice toward both conservative and liberal groups. This manipulation allowed researchers to simulate a “perceived power threat” and observe its effect on participants’ levels of ideological prejudice.

The results showed that when participants imagined that their opposing political party held power, their ideological prejudice toward opposing groups increased. This experimental evidence reinforced the study’s main hypothesis that ideological prejudice intensifies in response to opposition or perceived powerlessness within the political structure.

The results “led us to conclude that ideological prejudice is robustly heterogeneous,” the researchers stated. “Thus, the scientific debate about (a)symmetric ideological prejudice might benefit from focusing on when and why ideological prejudice is stronger in conservatives, progressives, or neither, instead of arguing that one of the three is the case throughout time and across situations.”

However, this study has some limitations. The researchers acknowledged that while they found strong evidence for the influence of political power on ideological prejudice, other factors could contribute to this effect. Events such as economic downturns, social movements, and global crises like pandemics may also heighten or reduce ideological biases. Additionally, the study primarily focused on ideological dynamics within the United States, which means these findings may not apply to other countries or cultures with different political systems and values.

The study, “Political Rule (vs. Opposition) Predicts Whether Ideological Prejudice Is Stronger in U.S. Conservatives or Progressives,” was authored by Johanna Woitzel and Alex Koch.