This paper uses data on bill sponsorship and co-sponsorship in the U.S.
House of Representatives to estimate gender differences in cooperative behavior. To address the potential selection of female representatives, we employ a Regression Discontinuity de- sign that focuses on mixed-gender electoral races decided by a narrow margin, where the gender of the elected representative is plausibly exogenous. We document two main findings. First, simple OLS estimator shows that women are able to recruit a larger number of cosponsors on the bills that they sponsor, but this difference largely vanishes in the RD specifications. Second, male and female representatives are equally likely to sponsor legislation that attracts bipartisan support. However, this result masks important differences by party affiliation: female Democrats are less likely, and female Republicans are more likely to sponsor legislation that attracts bipartisan support.
Female Republicans are especially likely to attract support from female Democrats.
This is particularly true on bills that address issues more relevant for women, over which female Republicans have possibly less support within their own party. We interpret these results as evidence that cooperation is mostly driven by a commonality of interest, rather than gender per se.