The Bipartisan Path Revisited: Collaboration and Legislative Effectiveness in the U.S. States

Monday, July 21, 2025

Does bipartisan collaboration enhance legislative success in U.S. state legislatures, as it does in Congress? This Center for Effective Lawmaking (CEL) working paper extends Harbridge-Yong, Volden, and Wiseman’s (2023) work, which finds that members of Congress are more effective lawmakers when they attract a greater share of cosponsors from the opposing party. Ph.D. candidate (and CEL Graduate Affiliate) Mackenzie R. Dobson adapts their framework to the state level using an original dataset of 401,720 bills introduced across 43 state legislatures between 2009 and 2018. These data enable new, fine-grained measures of bipartisanship, capturing both legislators’ ability to attract out-party cosponsors and their willingness to cosponsor legislation introduced by the opposing party. On the whole, bipartisanship is positively associated with lawmaking success in the states, as it is in Congress. Notably, however, substantial variation across legislatures—such as institutional rules and design, party competition, and majority security—likely shape the contours of bipartisan collaboration. These findings underscore the value of state legislatures for evaluating how structural features of policymaking environments condition cross-party collaboration and open avenues for comparative institutional research.

To learn more, read the full report here.

“A Close-Up Shot of People Shaking Hands” by Gustavo Fring is licensed under CC BY-ND 2.0.