Political polarisation has become one of the defining problems of modern democracy, with millions of people across the Western world viewing those who vote differently as not just wrong, but morally inferior. New research suggests that this deep-seated hostility may be more malleable than previously assumed, and that something as straightforward as exposure to the good deeds of political opponents could meaningfully shift attitudes. The findings were published in Social Psychological and Personality Science.
Psychologists Tal Moran of the Open University of Israel and Eva Walther of the University of Trier conducted three experiments involving American Democrats and Republicans, testing whether a structured moral learning treatment could reduce what researchers call affective polarisation. This refers to the gap between strong positive feelings towards one’s own party and strong negative feelings towards the opposing party, a pattern that has intensified sharply in the United States and across many other democracies in recent decades.
In the study, participants were shown photographs of individuals identified as members of either the Democratic or Republican Party, alongside written descriptions of their behaviour. Those in the key experimental condition were exposed to moral actions attributed to members of the opposing party, such as donating a kidney to a colleague or rescuing a trapped animal from a burning building. Participants in a comparison condition saw moral behaviours associated with their own party instead.
The results were striking. Those who had been shown the out-party acting morally reported significantly reduced preference for their own political group, both immediately after the treatment and again two days later. Crucially, this effect appeared not only in self-reported attitudes but also in automatic measures of preference, assessed using the Implicit Association Test, which is designed to capture responses that people may not consciously control or wish to admit.
A second experiment replaced negative behaviours with neutral ones, confirming that the reduction in partisan bias did not require making one side look bad. Simply presenting the opposing party in a morally positive light was sufficient. A third experiment extended the findings to show that the changed attitudes applied not just to individual politicians or party members, but to the broader political group as a whole.
The researchers argue that the approach works because morality is a primary lens through which people evaluate others, and because moral values such as honesty, courage, and compassion tend to be broadly shared across political divides even when policy positions diverge sharply. Presenting multiple examples rather than a single moral exemplar also appeared to help prevent participants from dismissing the individuals they encountered as exceptional cases that did not represent their party more widely.
The study’s authors acknowledge limitations. The research was conducted exclusively in the United States, and it remains unclear whether the effects would persist beyond 48 hours or translate into real-world behavioural changes such as willingness to vote for cross-party candidates. The treatment also had no measurable effect on social distance, the degree to which people felt comfortable with political opponents as neighbours or family members.
The authors suggest the findings could inform political communication strategies, public education programmes, and social media campaigns aimed at reducing partisan hostility.