When Do Low Roll Rates Indicate Party Influence? Evidence from Counterfactual Roll Rates

Abstract

A simulation-based counterfactual is one way to solve the observational equivalence challenge that seemingly “partisan” majority-party roll rates can be observed in the absence of any actual party influence. We simulate no-partisan-agenda-control counterfactual roll rates and apply them across sessions of the US House of Representatives and 86 state legislative chambers to evaluate the extent to which observed roll rates provide evidence for party influence on the legislative agenda. After assessing and controlling for the baseline risk of majority-party rolls, there is significant evidence of party influence on roll rates in some state legislatures, particularly those with rules that grant parties more agenda power, and in the post-Reed’s-rules House of Representatives. Institutional rules interact with the (simulated) risk of a majority roll to shape observed roll rates across chambers and across time.