The month following the November 2015 Paris terrorist attack, incidents of hate crimes in the United States against Muslims spiked to 45, up from an average of 13 monthly incidents the previous four years, according to FBI data. However, after the 2017 Las Vegas shooting by a white male, the same directed anger toward white men never materialized.

Emile Bruneau, director of the Peace and Conflict Neuroscience Lab at the Annenberg School for Communication, wanted to understand why such collective blame—holding an entire group responsible for the actions of one individual—applies to some populations but not others.  

“Should we close down the mosque where a terrorist prays? Should we punish his family? Legally and traditionally, we reject this,” Bruneau says. “You can’t hold the mosque responsible, just like you can’t hold a town responsible if someone there is a white supremacist who commits murder. I became interested in how people try to combat this tendency.”

Looking specifically at the question of collective blame toward Muslims, Bruneau, along with Emily Falk, an associate professor of communication at Annenberg, and Nour Kteily of Northwestern University, built a three-step experiment.

In the first phase, 2,000 participants watched one of eight videos depicting Muslims in distinct ways. A short documentary, for example, highlighted the relationship between a Muslim cleric and his wife. In another, a researcher spoke about her work on American attitudes toward Muslims. The idea was to determine which video would most effectively reduce collective culpability, and the winner was a clip of a Muslim woman on Al Jazeera News.

“During a 15-second piece of the interview, she notes that blaming all Muslims for the attacks in Paris is like blaming all Christians for the Westboro Baptist Church or the KKK,” Bruneau says. Directly calling out the double standard, he adds, probably made people realize their hypocritical—and likely subconscious—thought processes. 

Next, Bruneau and colleagues randomly assigned 1,000 different individuals to watch one of the same eight videos, this time to forecast which option would most effectively reduce the number of participants who blamed all Muslims for an act committed by one Muslim. Participants did not make accurate predictions, concluding that the Al Jazeera video clip that turned out to be most effective would have no effect at all.  

With this data in hand, the researchers then split a third set of 600 participants into two randomized groups. Those in the experimental group went through an exercise that offered scenarios about several terrorist attacks committed by white males. After hearing about such events, participants were asked how responsible they—and white people generally—were for those attacks, and then how responsible Christians are for the actions of Christian extremists like the KKK. After making these judgments about their own responsibility, and the collective responsibility of white people and Christians, participants in the experimental group were asked how responsible Muslims are, in general, for a specific attack by Muslim extremists.

Participants in a control group were asked straight away how responsible all Muslims were for the attack by Muslim extremists.

On a scale of 0 to 100, with 0 being “not at all responsible” and 100 being “completely responsible,” people who hadn’t completed the exercise typically placed Muslim blame between 35 and 40.

For those who had, that reported number dropped to 10, and they became less likely to sign an anti-Muslim petition.

Bruneau thinks this is the case because humans don’t like feeling hypocritical.

“It creates cognitive dissonance, and we want to relieve that because it’s uncomfortable,” he says. “If you put hypocrisy in someone’s face, if you use it as a weapon rather than a tool, you’ll probably get a reaction. People might double down and become combative. But if you can gently point to it, they’re more likely to change.”

Moreover, Bruneau says it’s possible that transformation can last. In another version of the same study conducted with Spaniards, Bruneau checked in with participants a month later. Their level of empathy was nearly the same as it had been just after they completed the experiment.