Unpacking pivotal politics: exploring the differential effects of the filibuster and veto pivots

Abstract

Formal models of politics regularly combine assumptions about a variety of actors and institutions to produce equilibrium expectations, which serve as the primary target for empirical testing. Yet the underlying assumptions can vary in their accuracy among actors and across time and context. We focus on the pivotal politics model of lawmaking and argue that a full evaluation of the theory requires a granular analysis of its two primary components: the filibuster and veto “pivots” in Congress. We show that both types of pivots contribute to the success of pivotal politics in explaining postwar lawmaking, but that the relevance of each varies based on institution-specific contexts. Specifically, the filibuster pivot has little explanatory power before the 1970s, when norms of filibuster use were quite restrictive, while the veto pivot’s explanatory power is limited to situations in which the president has sufficient public backing to be a force in the legislative process.