The extant literature suggests that legislatures are important to democratic systems because, when effective, legislatures monitor the actions of the executive, restrain it, increase accountability, and may even protect the democratic system from backsliding or collapsing. However, existing measures of legislative prowess are limited in terms of theoretical, temporal, or spatial coverage. In this paper, we use V-Dem data to present a new multi-dimensional measure of legislative power vis-à-vis the executive, disaggregating the concept to policymaking, the ability to impose constraints on the executive, and legislatures’ institutional resources. We focus further on a number of important applications of our measure -- analyzing the conditions under which it is conducive to democratic survival, to horizontal accountability, and to the congruence between citizens' preferences and government policies.
