Bribery or just desserts? Evidence on the influence of Congressional reproductive policy voting patterns on PAC contributions from exogenous variation in the sex mix of legislator offspring

Evidence on the relationship between political contributions and legislators’ voting behavior is marred by concerns about endogeneity in the estimation process. Using a legislator’s offspring sex mix as a truly exogenous variable, we employ an instrumental variable estimation procedure to predict the effect of voting behavior on political contributions. Following previous research, we find that a legislator’s proportion daughters has a significant effect on voting behavior for women’s issues, as measured by score in the “Congressional Record on Choice” issued by NARAL Pro-Choice America. In the second stage, we make a unique contribution by demonstrating a significant impact of exogenous voting behavior on PAC contributions, lending further credibility to the hypothesis that Political Action Committees respond to legislators’ voting patterns by “rewarding” political candidates that vote in line with the positions of the PAC, rather than affecting those same votes – at least in this high-profile policy domain.

► Instrumental variable estimation procedure to predict the effect of voting behavior on Congressional political contributions.
► A legislator’s proportion daughters has a significant effect on voting behavior for women’s issues.
► Second stage shows a significant impact of exogenous voting behavior on PAC contributions.