By systematically altering or selecting the faces that participants are presented with, researchers have been able to examine how variations in facial appearance bias human decisions. These studies have shown not just correlations, but causal evidence that facial appearances influence voting, economic exchanges, and legal judgments. People tend to draw inferences about personality characteristics, above and beyond what we might assume based on things like gender, ethnicity, or expression. Social attributions from faces alone tend to be constructed from how common facial features are within a culture, cross-cultural norms (e.g., inferences on masculinity/femininity), and idiosyncrasies like resemblance to friends, colleagues, loved ones, and, importantly, ourselves. Olivola’s research has shown that these facial attributions people make have serious implications for how people are treated, and their outcomes in life. The especially unfortunate part of these inferences is how heavily they factor into critical decisions, in lieu of actual facts.

“The fact that social decisions are influenced by facial morphology would be less troubling if it were a strong and reliable indicator of people’s underlying traits,” the researchers write in today’s article. “Unfortunately, careful consideration of the evidence suggests that it is not.”