An important paper by Bruce Western and Jake Rosenfeld which is forthcoming in the American Journal of Sociology finds that the decline in private sector union density in the U.S. (from 34 per cent to 8 per cent for men, and from 16 per cent to 6 per cent for women) explains one fifth to one third of the increase in inequality of hourly earnings over the period 1973 to 2007. This shows declining union density to be a much greater causal factor than most studies have found.

The novel contribution of the authors is to show empirically through a sophisticated quantitative analysis that a fall from high to lower union density in industrial/regional clusters is associated with rising levels of wage inequality among non-union workers in those clusters.

The path from strong unions to greater equality among non-union workers likely runs through two channels. The first is fear; non-union employers in a strong union environment will pay higher wages to lower paid workers in order to avoid unionization. The second and likely stronger channel is norms. Strong unions establish norms of fair wage differences between management and workers and between groups of workers which spill over into the non-union sector.

This article was first posted on The Progressive Economics Forum.

Thank you for choosing rabble.ca as an independent media source. We’re a reader-supported site — visited by over 315,000 unique visitors during the election campaign! But we need money to grow. Support us as a paying member (click here) or in making a one-off donation (click here).