How would you try to make a good impression at a job interview? Beyond the obvious (making eye contact, smiling, and attempting to appear knowledgeable and competent), what other tactics might you deploy?

One subtle approach some jobseekers might take involves the use of social identity. Humans are notoriously cliquey – establishing some shared sense of belonging with a new acquaintance can establish feelings of closeness and trust, and might result in favourable treatment.

Perhaps you have in mind an interviewee with blond hair and blue eyes, who notices the interviewer shares similar features. Is the interviewee recommended to casually suggest that the two can therefore look forward to an effective working relationship?

Of course not. These days such a strategy thankfully seems improbable, not only because of its moral repugnance, but also because it is hardly likely to work. (It feels less improbable that it might have been used in previous centuries, possibly with success, at job interviews in the world of colonial bureaucracy, for example.)

But other identities, especially political leanings, can play a big part in helping us to form connections – and use them to our advantage.

Shared identity does not only apply to sensitive characteristics such as race and gender. In fact, our social identities are multidimensional and include some traits regarded as more frivolous. As former Labour MP Frank Roy put it: “Monday to Friday, my body belongs to the trade union movement. Saturday my heart belongs to Celtic. And Sunday, my soul belongs to the Catholic Church.”

With most people you might meet, you are a clique member on some dimensions, but an outsider on others.

In recent research, I explored whether people deploy identity characteristics in strategic ways. I ran an economic experiment, creating scenarios where one person’s success depends on how someone else treats them.

Job interviews are like this, as the interviewee’s success depends on the interviewer’s decision. But there are many other examples of how this could work in business and our wider lives. For instance, an Airbnb host’s profitability depends on guests choosing to do business with them.

In my experiment, involving 416 students in the UK, interactions consisted of a decision-maker selecting amounts of real money to transfer to an “applicant”, who I will refer to as a dependant.

Crucially, before their interaction, the dependant could select which of several identity characteristics to reveal to the decision-maker, in the same way as an Airbnb host picks which details to show on their profile.

They made this decision with full awareness of the decision-maker’s characteristics, understanding which revelations would mark them as an in-group member and which would set them apart in the out-group. Dependants also reported how they believed the decision-maker would treat them had they chosen to reveal each of their available characteristics.

The data made it possible to check how accurate these beliefs were, and whether dependants’ choices about what to reveal led to higher transfers than they would have obtained by revealing other characteristics.

Political leanings

The results showed decision-makers gave preferential treatment to in-group dependants, but the level of this favouritism depended on which dimension of identity I looked at. By far the strongest favouritism was based on political identity.

In the experiment, one of the things dependants could reveal was whether they supported or opposed Brexit. Decision-makers who were Remainers acted extremely generously towards Remainers and harshly towards Brexiters. Those who were Brexiters did the opposite.

Decision-makers’ in-group favouritism based on other characteristics, such as race and gender, tended to be much milder. This could be because people find discrimination based on race or sex to be distasteful or morally unacceptable – especially when they know their behaviour is being observed. Political leanings, on the other hand, might be said to be a choice.

Importantly, dependants correctly anticipated that political identity would have the biggest impact. Consequently, they had a very strong tendency, when they knew their view on Brexit matched the decision-maker’s, to reveal it – and to conceal it when they knew their views diverged. In contrast, dependants were rather reluctant to reveal shared race or gender, perceiving this to be less beneficial.

On average, dependants profited from their decisions, obtaining better treatment from decision-makers than would have occurred had they randomly selected what to reveal. So the deliberate use of social identity appears to be an effective strategy.

Overall, this research shows people often use their identity, especially their political stances, strategically in their interactions with, for example, potential employers or business contacts.

In today’s world, political identity has become one of our strongest dividing lines and people mostly interact with like-minded others. But it is worth thinking about how strategically emphasising shared political affiliations to strengthen a relationship might actually be making this polarisation even worse.