Understanding social norms can provide insights into the internal, group-level dynamics that may move groups towards hate or violence. How do group norms impact group members’ behavior? How do these norms evolve over time for a given group? The following primer defines social norms, describes how they are formed and their impact on behaviors, and examines the practical implications of this research.

Social norms are unwritten rules of behavior based on what is considered normal for or expected of members in a certain group.¹ There are a different types of norms:

  1. Descriptive norms: What people are actually doing.
  2. Perceived norms: What someone thinks all or most people are doing
  3. Injunctive norms: What someone thinks they should or should not be doing

Perceived norms are typically the most important for shaping behavior because this is what we think all or most people in our group are doing,² and therefore what we base our behavior on.

Studies have shown that norms have an enormous impact on our behavior,³,⁴ often predicting our behavior even better than our individual beliefs or attitudes towards a particular issue.⁵,⁶,⁷


  • We tend to overestimate negative behavior. A few loud voices advocating negative behavior (or even just talking about it) can have an outsized impact: they change what we think the norm is, and therefore how we behave.
  • Norms are powerful partly because they are related to belonging - and we are wired for belonging. For example, studies have actually shown that when we are rejected, the same part of our brain is activated as when we feel physical pain. Being rejected actually hurts us.⁸ We care most about the norms in the groups we are part of, and in particular, for our closest social groups.⁹ For instance, high schoolers care more about high school norms than adult ones, and care most about the norms in their clique than those of the general student body. In times of conflict, if our group is condoning or participating in hate or violence, we may feel increased pressure to do the same, even if doing so violates our privately held beliefs.
  • Norms are not static. They form and evolve alongside real or perceived challenges in our social environment. We are constantly - even if not consciously - assessing and updating our understanding of norms through signals from the groups we belong to (e.g. public statements, actions; or even marketing campaigns, social media,and the news).¹⁰
  • Some people have a bigger influence on norms than others - specifically, “norm referents” --people who are widely known across a particular social network, either because they are leaders or the “hubs” of social networks--tend to have a greater influence within that network.²,¹¹,¹²


Norms may encourage individuals harboring hate or prejudice to either act upon, or conceal, those views;⁷,¹³,¹⁴,¹⁵,¹⁶,¹⁷ they may also influence whether those opposing hate and prejudice choose to take action or stay silent.¹⁸,¹⁹

As conflicts evolve and identities become more rigid and exclusionary, norms and social pressures can shift to encourage support or participation in violence or harm.  As people face novel situations without clear rules or expectations for behavior,²,¹¹,¹²,²⁰,²¹,²² as in conflict, norm clues are more influential. In such situations, public rhetoric and observed actions can quickly shift group norms, particularly when connected to powerful emotions that lead people to more strongly identify with their group, such as fear and perceived threat.²³


Norms also impact prosocial behavior. For example, studies increasingly show the impact of conflict resolution media programming even in the most violent contexts.²⁴,²⁵,²⁶ Israeli and Palestinian children who viewed the show “Sesame Street” later endorsed more positive stereotypes and attributes of the out-group,²⁷ and Rwandans who listened to a pro-reconciliation radio program following the genocide were more likely to expect that open dissent and cooperation between ethnic groups would be deemed acceptable.⁵ Lastly, institutional shifts can also cause people to update their norm perceptions. When the U.S. Supreme Courts ruled in favor of marriage equality in 2015, it was shown to influence norm perceptions throughout the U.S. (though not personal attitudes).¹⁰

In summary, norms powerfully influence behavior; they matter the most for people’s own groups;⁹ and perceptions of norms are not static but are instead based on our understanding of the social environment, regardless of whether that assessment mirrors reality. Norms can positively or negatively impact expressions of hate or violence in society. Norms may restrain expressions of prejudice and prevent violence, creating expectations of inclusion and equality; or, they may be mobilized to increase the expectation of and social pressure to participate in expressions of hatred and violence, while silencing dissent.²⁸


  1. Norms are  unwritten rules of behavior that vary across groups.
  2. Norms are key drivers of behavior, as humans are hardwired to be part of groups.
  3. The perception of what the norm is- whether or not that perception is accurate- is what matters most in terms of dictating behavior.
  4. Norms can create powerful social pressure that fuel harmful and violent behaviors, as well as cooperation and prosocial behaviors.


  1. Consider who the ‘norm referents’ in a group are--be they well-respected leaders or “hubs” that are widely connected within a network. Can you work with them to set positive norms such as nonviolence and inclusivity? Sometimes these people can be identified through informal means--by mapping out key connectors in a community, and identifying informal and formal leaders who hold high esteem. Other times, you can actually conduct a social network exercise to identify “hubs” and appeal to their participation. Can you correct misperceptions about negative norms- in other words, show people that those advocating for harm and violence are the minority?
  2. Can you give examples of positive behavior for people to follow (showing rather than telling?)
  3. Be careful not to communicate a negative norm, for instance by saying “hate is everywhere.” Instead, communicate a social issue in a way that also communicates a positive norm, such as “While hate is on the rise, most citizens reject it vehemently.”

¹ Miller, D. T., Monin, B, & Prentice, D.A. (2000). Pluralistic ignorance and inconsistency between private attitudes and public behaviors. In D. J. Terry & M. A. Hogg (Eds.), Attitudes, Behavior, and Social Context: The Role of Norms and Group Membership, 95–113. Mahwah, NJ, US: Erlbaum.

² Paluck, E. L., & Shepherd, H. (2012). The salience of social referents: A field experiment on collective norms and harassment behavior in a school social network. Journal of Personality and Social Psychology, 103(6), 899–915.

³ Asch, S. E. (1955). Opinions and Social Pressure. Scientific American, 193(5), 31–35.

⁴ Cialdini, R. B., & Goldstein, N. J. (2004). Social Influence: Compliance and Conformity. Annual Review of Psychology, 55(1), 591–621.

⁵ Paluck, E. L. (2009). What's in a norm? Sources and processes of norm change. Journal of Personality and Social Psychology, 96(3), 594-600

⁶ Crandall, C. S., Miller, J. M., & White,Mark H.,,II. (2018). Changing norms following the 2016 U.S. presidential election. Social Psychological and Personality Science, 9(2), 186-192.;

⁷ Blanchard, F. A., Lilly, T., & Vaughn, L. A. (1991). Reducing the Expression of Racial Prejudice. Psychological Science, 2(2), 101–105.

⁸ Eisenberger, N. I., & Lieberman, M. D. (2004). Why rejection hurts: A common neural alarm system for physical and social pain. Trends in Cognitive Sciences, 8(7), 294–300.

⁹ Haslam, S. A., Oakes, P. J., McGarty, C., Turner, J. C., Reynolds, K. J., & Eggins, R. A. (1996). Stereotyping and social influence: The mediation of stereotype applicability and sharedness by the views of in-group and out-groupmembers. British Journal of Social Psychology, 35(3), 369-397.

¹⁰ Tankard, M. E., & Paluck, E. L. (2016). Norm perception as a vehicle for social change. Social Issues and Policy Review, 10(1), 181-211.

¹¹ Paluck, E. L., Shepherd, H., & Aronow, P. M. (2016). Changing climates of conflict: A social network experiment in 56 schools. Proceedings of the National Academy of Sciences, 113(3), 566–571.

¹² Valente, T. W., & Pumpuang, P. (2007). Identifying opinion leaders to promote behavior change. Health Education & Behavior: The Official Publication of the Society for Public Health Education, 34(6), 881–896.

¹³ Crandall, C. S., Eshleman, A., & O'Brien, L. (2002). Social norms and the expression and suppression of prejudice: The struggle for internalization. Journal of Personality and Social Psychology, 82(3), 359-378.

¹⁴ Stangor, C., Sechrist, G. B., & Jost, J. T. (2001). Changing racial beliefs by providing consensus information. Personality and Social Psychology Bulletin, 27(4), 486–496.

¹⁵ Wittenbrink, B., & Henly, J. (1996). Creating Social Reality: Informational Social Influence and the Content of Stereotypic Beliefs. Personality and Social Psychology Bulletin, 22(6).

¹⁶ Zitek, E. M., & Hebl, M. R. (2007). The role of social norm clarity in the influenced expression of prejudice over time. Journal of Experimental Social Psychology, 43(6), 867–876.

¹⁷ Monteith, M. J., Deneen, N. E., & Tooman, G. D. (1996). The Effect of Social Norm Activation on the Expression of Opinions Concerning Gay Men and Blacks. Basic and Applied Social Psychology, 18(3), 267–288.

¹⁸ Blanton, H., & Christie, C. (2003). Deviance Regulation: A Theory of Action and Identity. Review of General Psychology, 7(2), 115–149.

¹⁹ Miller, D. T., & Prentice, D. A. (2013). Psychological levers of behavior change. In E. Shafir (Ed.), The behavioral foundations of public policy, 301-309. Princeton, NJ, US: Princeton University Press.

²⁰ Bandura, A. (1986). Social foundations of thought and action, Englewood Cliffs, NJ, US: Prentice Hall.

²¹ Cialdini, R. B., & Trost, M. R. (1998). Social influence: social norms, conformity and compliance (4th ed.). In D. T. Gilbert, S. T. Fiske, & G. Lindzey (Eds.). The handbook of social psychology (Vol. 2), Boston, MA, US: McGraw-Hill.

²² Deutsch, M., & Gerard, H. B. (1955). A study of normative and informational social influences upon individual judgment. The Journal of Abnormal and Social Psychology, 51(3), 629–636.

²³ Kallgren, C. A., Reno, R. R., & Cialdini, R. B. (2000). A focus theory of normative conduct: When norms do and do not affect behavior. Personality and Social Psychology Bulletin, 26(8), 1002–1012.

²⁴ Bilali, R., Vollhardt, J. R., & Rarick, J. R. D. (2016). Assessing the Impact of a Media-based Intervention to Prevent Intergroup Violence and Promote Positive Intergroup Relations in Burundi. Journal of Community & Applied Social Psychology, 26(3), 221–235.

²⁵ Crisp, R., & Turner, R. (2009). Can Imagined Interactions Produce Positive Perceptions? Reducing Prejudice Through Simulated Social Contact. The American Psychologist, 64(4), 231–240.

²⁶ Johnson, D. R., Jasper, D. M., Griffin, S., & Huffman, B. L. (2013). Reading narrative fiction reduces Arab-Muslim prejudice and offers a safe haven from intergroup anxiety. Social Cognition, 31(5), 578–598.

²⁷ Cole, C., Arafat, C., Tidhar, C., Tafesh, W. Z., Fox, N., Killen, M., Ardila-Rey, A., Leavitt, L., Lesser, G., Richman, B., & Yung, F. (2003). The educational impact of Rechov Sumsum/Shara’a Simsim: A Sesame Street television series to promote respect and understanding among children living in Israel, the West Bank, and Gaza. International Journal of Behavioral Development, 27(5), 409–422.

²⁸ For an interesting discussion of social change in relation to changing norms and norm perceptions, see: Sunstein, C. R. (2017). Unleashed (SSRN Scholarly Paper ID 3025749). Social Science Research Network.