When I wrote this article, the Coronavirus had just been declared a pandemic by the World Health Organization,1 and the United States had declared a national emergency.2
Since then, health officials have tried (quite successfully) to promote behaviors that can reduce the spread and transmission of the Coronavirus — including the one we are all quite familiar with now, social distancing, or the practice of avoiding unnecessary contact with others in order to slow the transmission of the disease.
While social distancing is essential to slow the spread of COVID-19 — which in turn reduces the strain on our healthcare system and saves lives — it is personally costly for the individual, as it requires personal sacrifice (forget about going out to brunch).
As such, now more than ever it is important to understand how insights from behavioral science can promote prosocial behaviors and get people to prioritize shared over individual interests. One potentially powerful set of tools to promote behavioral change is social norms.
Social norms are overt or unspoken rules that govern what behaviors are viewed as appropriate in society. Norms are frequently enforced by other members of the group and violating a norm can result in anything from social disapproval or informal sanctions to ostracization.3
Our predilection to create and conform to social norms is thought to be universal, occurring in diverse societies and cultures across the planet, although their expression is likely culturally dependent.4 Children as young as 3 years old begin to shift their behavior in accordance with local social norms, suggesting that our sensitivity to norms arises early in development.5 Taken together, this early internalization and ubiquity of norms suggests that we have evolved an innate sensitivity to follow them.6
Research on social norms has found that they have a profound impact on behavior across a wide range of domains such as decreasing littering,7 improving energy conservation,8 increasing hygienic behavior,9 and reducing student gambling.10
To get a better sense of the influence of social norms on human behavior, let’s look at a foundational study of social norms by Robert Cialdini and colleagues.11
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An Illustrative Example
Petrified Forest National Park in northeastern Arizona is a vast swath of desert and colorful badlands known for its abundance of 225 million-year-old fossilized trees. Unfortunately, however, the park faces rampant theft of its’ petrified wood from visitors, which threatens to compromise its natural beauty.
In a bid to counteract this theft, the park teamed up with Cialdini and colleagues to see if they could help simply by rewording the messaging of signs around the park.
The authors manipulated whether signs displayed an injunctive norm, which refers to what is commonly approved or disapproved of (“please don’t remove the petrified wood”), or a descriptive norm, which refers to what is commonly done (“many past visitors have removed the petrified wood”). They also manipulated whether the norm was strong, such that it was negatively framed (“please don’t remove the petrified wood”), or whether the norm was weak, in that it was framed positively (“please leave the petrified wood”).
They found that people were significantly less likely to steal petrified wood from the park after seeing a sign that displayed an injunctive norm compared to a descriptive norm, with the lowest level of theft occurring when the sign reflected a strong injunctive norm.
The results of this study suggest that messages that convey a descriptive norm about what is commonly done (e.g., “many visitors have removed the petrified wood”) can backfire, resulting in greater levels of that behavior. This is because descriptive norms convey the message: “if everyone else is doing it, then it’s probably okay if I do it too”. Reframing this message around the injunctive norm, what others approve or disapprove of, is much more effective at changing behavior.
While this research is hardly hot off the press (the study described above was published in 1990), organizations and health officials have been slow to apply its insights. This is surprising, given that simply reframing messages in terms of social norms can offer a cheap but effective behavioral intervention.
Exactly how can we harness social norms for societal and organizational good? Research suggests three main ways to effectively utilize social norms.
First, as seen above, messages framed as injunctive norms have the strongest impact on behavior, above and beyond descriptive norms. For example, if you wanted to promote energy conservation by having hotel guests turn off their room lights, you should emphasize that most people disapprove of leaving lights on and wasting energy (an injunctive norm), rather than emphasizing that most people leave their lights on and waste energy (a descriptive norm).
Second, messages have a stronger impact on behavior when they are framed negatively, describing which behaviors are not approved of. In keeping with the energy conservation example, it is better to have a message that says: “save energy, do not leave your lights on”, rather than one that says: “save energy, remember to turn your lights off”.
Lastly, while you can make norms explicit through a sign or message, often norms are not so clear and salient, making them less effective at changing behavior. Norms are most effective at changing behavior when they are made focal in attention and brought to our conscious awareness — such as when explicitly stated on a sign or clearly modeled by another person. For example, if you see another hotel patron model the norm by turning their lights off as they leave their room, this makes the norm salient and would likely make you more prone to shut your lights off too.
Using Norms to Promote Social Distancing
With all that in mind, let’s return to the question at hand: how we can use social norms to promote social distancing?
First, we should describe messages urging social distancing as an injunctive norm by framing them in terms of what others approve of (e.g., “most people think social distancing is the right thing to do”). Indeed, framing messages about social distancing as a descriptive norm (“most people are not social distancing, contributing to the spread of the disease”) might actually be detrimental.
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Importantly, if conveying both descriptive and injunctive norms, the norms should align, as it would be counter-productive to have the normative information conflict.11 For example, communicating that most people aren’t social distancing but approve of others who are would likely result in less social distancing relative to messages that convey consistent normative information (i.e., “everyone is social distancing and approve of others who are too”) or only conveys the injunctive norm.
Second, we should frame the injunctive norm negatively (“do not go to gatherings of more than 25 people”) rather than positively (“only go to gatherings of less than 25 people”). This distinction is subtle yet powerful, and can result in significant differences in behavior.
Lastly, it’s important to induce a normative focus so people are more likely to remember and follow the norm. That can take the form of a steady stream of reminders and messages from the media and public health experts. Influencers and celebrities could also model the norm of social distancing via social media, such as this video currently trending on Twitter featuring Mel Brooks.
In sum, research on social norms offers powerful insights for organizations and public health officials on how to promote prosocial behavior. In a time of global crisis, these insights are more important than ever.
 Gumbrecht, J. & Howard, J. (2020, March 11). WHO declares novel coronavirus outbreak a pandemic. CNN, retrieved from https://www.cnn.com.
 Savage, S. (2020, March 13). Trump Declared an Emergency Over Coronavirus. Here’s What It Can Do. New York Times, retrieved from https://www.nytimes.com.
 Fehr, E., Fischbacher, U., & Gächter, S. (2002). Strong reciprocity, human cooperation, and the enforcement of social norms. Human Nature, 13(1), 1-25.
 House, B. R., Kanngiesser, P., Barrett, H. C., Broesch, T., Cebioglu, S., Crittenden, A. N., Erut, A., Lew-Levy, S., Sebastian-Enesco, C., Smith, A.M. and Yilmaz, S. & Yilmaz, S., & Silk, J. (2020). Universal norm psychology leads to societal diversity in prosocial behaviour and development. Nature Human Behaviour, 4(1), 36-44.
 House, B. R. (2018). How do social norms influence prosocial development?. Current Opinions in Psychology, 20, 87-91.
 Chudek, M., & Henrich, J. (2011). Culture–gene coevolution, norm-psychology and the emergence of human prosociality. Trends in Cognitive Sciences, 15(5), 218-226.
 Cialdini, R. B., Reno, R. R., & Kallgren, C. A. (1990). A focus theory of normative conduct: recycling the concept of norms to reduce littering in public places. Journal of Personality and Social Psychology, 58(6), 1015.
 Goldstein, N. J., Cialdini, R. B., & Griskevicius, V. (2008). A room with a viewpoint: Using social norms to motivate environmental conservation in hotels. Journal of Consumer Research, 35(3), 472-482.
 Leoniak, K. J., & Maj, K. (2016). A slice of hygiene: justification and consequence in the persuasiveness of prescriptive and proscriptive signs. Social Influence, 11(4), 271-283.
 Larimer, M. E., & Neighbors, C. (2003). Normative misperception and the impact of descriptive and injunctive norms on college student gambling. Psychology of Addictive Behaviors, 17(3), 235.
 Cialdini, R. B., Demaine, L. J., Sagarin, B. J., Barrett, D. W., Rhoads, K., & Winter, P. L. (2006). Managing social norms for persuasive impact. Social Influence, 1(1), 3-15.
About the Author
Paul is a PhD student in Psychology at Boston College. His research applies behavioral economics and evolutionary psychology to study social cognition and morality, with a focus on understanding the ultimate and proximate mechanisms that underlie cooperation and punishment.