Pivots and the gridlock interval
Krehbiel (1998) placed legislators on a single ideological dimension and argued that lawmaking requires the consent not of a simple majority but of the filibuster pivot and the veto-override pivot. When current policy lies between these pivots, any change is blocked by someone and gridlock results. Brady and Volden (1998) offered a similar 'revolving gridlock' model. The logic can be seen as extending the median voter theorem to supermajoritarian institutions.
Link to the divided government debate
Mayhew (1991) sparked debate by reporting that the number of major laws did not fall much under divided government. Pivotal politics supported this result theoretically: gridlock can occur under unified government because of the filibuster, and lawmaking is possible under divided government if the pivots agree. Cameron (2000) analyzed how veto threats reshape bills during bargaining.
Evidence and assessments
Binder (1999) measured gridlock as the share of salient issues left unresolved and showed that ideological distance between parties and differences between chambers increase it. Chiou and Rothenberg (2003) reported that adding party discipline to the pivotal model improves its fit. Tsebelis's (2002) veto player theory generalized the same intuition to institutions across countries.
FAQ
- What is pivotal politics in simple terms?
- A theory that what matters for passing a law is who casts the decisive last vote that must be won over.
- What is the gridlock interval?
- The range of policies lying between the filibuster pivot and the veto pivot, where the status quo is hard to move in any direction.
Sources reviewed: 2026-10-26
References
- Krehbiel, K. (1998). Pivotal politics: A theory of U.S. lawmaking. University of Chicago Press. The founding statement of the theory.
- Brady, D. W., & Volden, C. (1998). Revolving gridlock: Politics and policy from Carter to Clinton. Westview Press. A parallel gridlock-interval model.
- Mayhew, D. R. (1991). Divided we govern: Party control, lawmaking, and investigations, 1946–1990. Yale University Press. Divided government and lawmaking.
- Binder, S. A. (1999). The dynamics of legislative gridlock, 1947–96. American Political Science Review, 93(3), 519–533. Measuring gridlock.
- Chiou, F.-Y., & Rothenberg, L. S. (2003). When pivotal politics meets partisan politics. American Journal of Political Science, 47(3), 503–522. Adding parties to the model.
- Cameron, C. M. (2000). Veto bargaining: Presidents and the politics of negative power. Cambridge University Press. Presidential veto bargaining.
- Tsebelis, G. (2002). Veto players: How political institutions work. Princeton University Press. The comparative veto-player framework.