People judge members of their own circles more harshly than they judge individuals from other groups for the same transgressions, new Cornell research has found.

Morality plays a central role in this phenomenon, the researchers found: Because morality is a social glue that holds a community together, when someone breaks those moral rules inside the group, it is perceived as more of a threat than when outsiders break the same rules in their own groups.

“When we’re part of a group, we feel a strong connection to the people in our group, and so we feel they are more likeable or more trustworthy,” said Simone Tang, assistant professor at the Peter and Stephanie Nolan School of Hotel Administration and a co-author of “Morality’s Role in the Black Sheep Effect: When and Why Ingroup Members Are Judged More Harshly Than Outgroup Members for the Same Transgression,” published Sept. 28 in the European Journal of Social Psychology.

“However, at the same time, when someone from our group does something morally wrong, it can threaten our social ties and reflect poorly on the whole group, so we judge them harshly to protect the group as a whole,” Tang said.

Tang’s co-authors include Steven Shepherd, associate professor at Oklahoma State University’s Spears School of Business, and Aaron Kay, professor at Duke University’s Fuqua School of Business.

“Ingroup” members may be family or friends and who may share the same political beliefs, hail from the same organization, or share the same nationality. In contrast, the “outgroup” may be from a different country or different institution. Contrary to prevalent wisdom that ingroup members always judge other ingroup members more favorably than outgroup members, they found that people made harsher moral judgments against the ingroup transgressor.

Across six studies, 2,361 university students and working American online community members either learned that an ingroup member had behaved badly toward another person in their group, or an outgroup member had done the same thing to another person in the outgroup. For example, students either read that a professor from their own university had been abusive toward other classmates or that a professor from the rival university was abusive toward rival classmates.

The researchers found that moral violations, such as gender discrimination, engendered harsher judgments toward ingroup members than non-moral violations, such as tardiness. This indicated that people cared about an ingroup member’s violation when the social glue of the community – morality – is threatened.

The professors also tested whether the severity and the context of the harm caused by the wrongdoing matters. For example, they found that if someone in your group hurts someone else badly, you might judge them more harshly than if they did something that didn’t hurt anyone but was still morally wrong. And if a member of your group does something morally wrong in a situation where their actions harm your group’s social harmony, you might judge them more severely than if it happened in a context that did not threaten the group’s social bonds.

“We hope that our research can help explain real-world puzzles,” Tang said. “In the world of politics, for example, our results provide a different perspective on our current polarized political landscape. Whereas the prevailing thought is that Democrats and Republicans view each other as outgroup members, our research suggests that perhaps the demonization of the other party happens because they view each other as ingroup members (e.g., Americans), hence rendering harsher moral judgments when another ingroup member holds an opposing view. We increasingly see splintering within our groups, and understanding when and why we denigrate and vilify those in our group will be crucial.”

Sarah Magnus-Sharpe is director of PR and media relations for the Cornell SC Johnson College of Business.