Americans are, compared with populations of other countries, particularly enthusiastic about the idea of meritocracy, a system that rewards merit (ability + effort) with success. Americans are more likely to believe that people are rewarded for their intelligence and skills and are less likely to believe that family wealth plays a key role in getting ahead. And Americans’ support for meritocratic principles has remained stable over the last two decades despite growing economic inequality, recessions, and the fact that there is less mobility in the United States than in most other industrialized countries.

This strong commitment to meritocratic ideals can lead to suspicion of efforts that aim to support particular demographic groups. For example, initiativesdesigned to recruit or provide development opportunities to under-represented groups often come under attack as “reverse discrimination.” Some companies even justify not having diversity policies by highlighting their commitment to meritocracy. If a company evaluates people on their skills, abilities, and merit, without consideration of their gender, race, sexuality etc., and managers are objective in their assessments then there is no need for diversity policies, the thinking goes.

The paradox of meritocracy builds on other research showing that those who think they are the most objective can actually exhibit the most bias in their evaluations. When people think they are objective and unbiased then they don’t monitor and scrutinize their own behavior. They just assume that they are right and that their assessments are accurate. Yet, studies repeatedly show that stereotypes of all kinds (gender, ethnicity, age, disability etc.) are filters through which we evaluate others, often in ways that advantage dominant groups and disadvantage lower-status groups. For example, studies repeatedly find that the resumes of whites and men are evaluated more positively than are the identical resumes of minorities and women.

This dynamic is precisely why meritocracy can exacerbate inequality—because being committed to meritocratic principles makes people think that they actually are making correct evaluations and behaving fairly. Organizations that emphasize meritocratic ideals serve to reinforce an employee’s belief that they are impartial, which creates the exact conditions under which implicit and explicit biases are unleashed.

“The pursuit of meritocracy is more difficult than it appears,” Castilla said at a recent conference hosted by the Clayman Institute for Gender Research at Stanford, “but that doesn’t mean the pursuit is futile. My research provides a cautionary lesson that practices implemented to increase fairness and equity need to be carefully thought through so that potential opportunities for bias are addressed.” While companies may want to hire and promote the best and brightest, it’s easier said than done.