At least when it comes to female politicians, perhaps you can judge a book by its cover, suggest two UCLA researchers who looked at facial features and political stances in the U.S. House of Representatives.
"Female politicians with stereotypically feminine facial features are more likely to be Republican than Democrat, and the correlation increases the more conservative the lawmaker's voting record," said lead author Colleen M. Carpinella, a UCLA graduate student in psychology.
The researchers also found the opposite to be true: Female politicians with less stereotypically feminine facial features were more likely to be Democrats, and the more liberal their voting record, the greater the distance the politician's appearance strayed from stereotypical gender norms.
In fact, the relationship is so strong that politically uninformed undergraduates were able to determine the political affiliation of the representatives with an overall accuracy rate that exceeded chance, and the accuracy of those predications increased in direct relation to the lawmaker's proximity to feminine norms.
"I suppose we could call it the 'Michele Bachmann effect,'" said Kerri Johnson, the study's senior author and an assistant professor of communication studies and psychology at UCLA.
The findings are forthcoming online in the peer-reviewed Journal of Experimental Social Psychology.
The work was inspired by prior research that has shown that Americans have a better-than-chance ability to determine whether someone is a Democrat or a Republican on the basis of appearance alone. The mechanism behind these judgments, however, is not well understood.
"At least when it comes to female politicians, assessing how much a face reflects gender norms may be one way of guessing political affiliations," said Johnson.
Carpinella and Johnson focused on the House of Representatives because the body was large enough to yield statistically valid results and its members would not be as easily recognized by study subjects as members of more high-profile political bodies, such as the U.S. Senate.
They started the project by feeding portraits of 434 members of the 111th House of Representatives into a computer modeling program used by researchers in their field. Loaded with a database of hundreds of scans of faces of men and women, the FaceGen Modeler allows researchers to measure how much the details of any one face approach the average for either gender.
The model compared each representative's face to the norm on more than 100 subtle dimensions, including the shape of the jaw, the location of eyebrows, the placement of cheek bones, the shape of eyes, the contour of the forehead, the fullness of the lips and the distance between such features as the bottom of the nose and the top of the lip. Armed with these dimensions, the researchers were able to arrive at an amalgamated score assessing the extent to which the face exhibited characteristics common to men or to women. Theoretical values ranged from -40 (highly male-typed) to +40 (highly female-typed).
"We weren't looking at hairstyle, jewelry or whether a person was wearing make up or not," Carpinella said. "We wanted to get an objective measure of how masculine or feminine a face is, based on a scientifically derived average for male or female appearance."
In addition to party affiliation, the researchers took into account each politician's DW–NOMINATE score, a scale developed by political scientists that uses voting records to determine how conservative or liberal a lawmaker is.
Because the GOP is more frequently associated with policies that uphold traditional sex roles, the researchers expected to find that Republican representatives of both sexes would have more sex-typical faces than their counterparts across the aisle. The theory, however, did not hold for male politicians. In a finding that the researchers do not view as a particularly revealing, the faces of male Republicans, on average, scored as less masculine than the faces of their Democratic counterparts.
"The Democratic Party is associated with social liberal policies that aim to diminish gender disparities, whereas the Republican Party is associated with socially conservative policy issues that tend to bolster traditional sex roles," Johnson said. "These policy platforms are manifest in each party's image — apparently also in the physical characteristics exhibited by politicians."