Newswise — BLOOMINGTON, Ind. -- Bisexual men and women are paid less for doing the same jobs than similarly qualified heterosexual men and women, according to Indiana University research that breaks new ground by treating bisexual individuals as distinct from gay men and lesbians in the workplace.

The study, "Sexual Orientation in the Labor Market," was published online today by the American Sociological Review, the flagship journal of the American Sociological Association. The author is Trenton D. Mize, a doctoral student in the Department of Sociology in the College of Arts and Sciences at IU Bloomington.

Mize finds that gay men and lesbians are also treated differently from heterosexual men and women when it comes to pay. But those differences, he said, are largely explained by the fact that earnings are correlated with whether employees are married and have children.

For bisexual men and women, the evidence is "highly suggestive" that workplace discrimination is a factor leading to lower pay. The data don't prove discrimination causes lower pay, but Mize was able to rule out many alternative explanations for the wage gap, such as age, education and occupation. Also, bisexual men and women do report unfair treatment from others, bolstering the idea that they face discrimination.

Mize said the findings lend support to arguments for nondiscrimination laws and policies.

"There is currently no federal law prohibiting labor market discrimination based on sexual orientation, and a majority of states in the U.S. still allow discrimination based on sexual orientation," Mize said. "I show that sexual orientation is associated with wages -- with bisexual men and women being paid less -- underlining the importance of legal protections."

Previous studies of sexual orientation in the labor market have taken a "binary" approach, he said, comparing heterosexual with non-heterosexual men and women. The reason is that data available to researchers often lacked enough gay, lesbian, and bisexual men and women to evaluate each group separately.

Mize was able to reach statistically reliable conclusions by drawing on two large data sets: the General Social Survey, which is representative of the adult population in the U.S. and provided over 20 years of data; and the National Longitudinal Study of Adolescent to Adult Health, a large data set that is representative of young adults. That let him conduct separate analyses for heterosexual men and women, gay men, lesbians, and bisexual men and women.

The study finds some evidence that gay men are paid less than similarly qualified heterosexual men. But Mize said the discrepancy appears to exist primarily because married men and fathers are paid more than unmarried and childless men, and gay men are less likely to be married or to be fathers.

Similarly, there is evidence that lesbians earn more than similarly qualified heterosexual women. But that gap seems to reflect the fact that mothers earn less than non-mothers, and lesbians are less likely than heterosexual women to be mothers.

The likelihood of being married or being a parent doesn't fully account for the lower wages earned by bisexual men and women, Mize said.

He said the results suggest that any sociological analysis of sexual orientation "should take a more nuanced view, moving beyond thinking of sexual orientation as a binary." For example, some studies have found that bisexual men and women tend to have worse health outcomes than heterosexual men and women, gay men or lesbians. Other research, including work by Mize and his colleagues, has shown that social stereotypes vary greatly for lesbian, gay and bisexual individuals.

Journal Link: American Sociological Review