In-Group Bias: How and Why We Favor Our Group Members

In-Group Bias: How and Why We Favor Our Own Group Members - Fallacy in Logic

We humans like belonging to groups. Often, we join them because we want to feel connected and wish to form alliances with individuals that we have something in common with. This isn’t only useful, but essential too.

In every group, there’s also a social consciousness to maintain an identity and favor its members over “outsiders.” In psychology, there is a specific name for this: in-group bias.

This article explores what the concept is all about and examines a few examples to help you better understand it.

What is In-Group Bias? 

In-group bias is a cognitive bias — an innate tendency that we all have in common — that describes how we favor in-group members over individuals who don’t belong to that group.

Naturally, we tend to display a more positive and helpful attitude and generally give preferential treatment towards people we are connected to.

The effects of this are two-fold:

  • Strong sense of belonging and favoritism towards group members can be beneficial for mental health and self-esteem.
  • In some situations, it may lead to harmful behavior towards people outside of one’s group or class, as in the case of racial discrimination.

Moreover, the bias was first identified in the early 1900s and has since become widely-known in psychology. It’s important, in particular, because it displays itself in various group identities, such as ethnicity, religious or geographical beliefs, political ideologies, gender, and age.


In-group bias can occur in various ways. For example, it can present itself as a competition between two or more parties. If there is a competition for limited resources among them, people in one group tend to react and behave negatively in regards to other groups. In general, highly competitive environments spur the need for people form alliances and win against others.

A simple real-world example of the bias would be sports allegiances: sports fans are, more often than not, biased to favor people who back the same team as they do. Additionally, you can also find it at lunch tables in schools where students who see themselves as part of a certain group tend to sit only amongst each other.

Why Does it Occur?

In-Group Bias: How and Why We Favor Our Own Group Members - Fallacy in Logic

In accordance with the Social Identity Theory, one major reason behind this bias is the need to maintain and improve one’s self-esteem, which is greatly sourced from social connections, such as family and friend groups. They provide us with a social identity, as well as the knowledge that people close to us will view us more positively as opposed to “outside” people.

Our basic biological makeup further encourage us to engage in in-group favoritismResearch shows that oxytocin, one of the hormones in our bodies, is responsible for the development of trust towards individuals of similar characteristics. This applies, for example, to race: nasally administered oxytocin causes individuals to behave more empathetically towards people of the same race.


Being a deeply rooted tendency, the in-group bias influences our judgment in ways that often end up going unnoticed. And, while it may help us feel a healthy connection to other people, it also may also give rise to neglect, discrimination, or other negative attitudes towards so-called outsiders. As such, learning about it and striving to reduce its grip on one’s self — for instance, by interacting with many other groups — can prove to be highly beneficial.

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