via ASA:

Union membership in America has declined significantly since the early 1970s, and that plunge explains approximately a fifth of the increase in hourly wage inequality among women and about a third among men, according to a new study in the August issue of the American Sociological Review.

“Our study underscores the role of unions as an equalizing force in the labor market,” said study author Bruce Western, a professor of sociology at Harvard University. “Most researchers studying wage inequality have focused on the effects of educational stratification—pay differences based on level of education—and have generally under-emphasized the impact of unions…

While the purpose of unions is to standardize wages for their members, Western and Rosenfeld find that even nonunion workers, if they’re in highly unionized industries, tend to have fairly equal wages, partly because nonunion employers will raise wages to the union level to discourage unionization.

In terms of policy implications, Western and Rosenfeld think their study could help reignite the dialogue on labor unions, which they believe has disappeared from economic debates in recent years.

“In the early 1970s, unions were important for delivering middle class incomes to working class families, and they enlivened politics by speaking out against inequality,” said Western. “These days, there just aren’t big institutional actors who are making the case for greater economic equality in America.”

Speaking of unions… Come support Utah teachers unions today at the downtown public library at 1 PM! We’ll be marching to the state office of education, so bring some water and dress accordingly!