Veto Player Theory

Basic concepts

Tsebelis (1995) called the actors whose agreement is necessary to change the status quo veto players. Actors specified by a constitution, such as a president or the chambers of a legislature, are institutional veto players; actors generated by the political process, such as the parties of a governing coalition, are partisan veto players. The set of policies that all veto players prefer to the status quo is called the winset. The more veto players there are, the greater the distances between them and the more cohesive each is internally, the smaller the winset becomes. A small winset makes the status quo hard to change, producing high policy stability. The theory generalizes discussions of checks and balances and the veto into a game-theoretic spatial model.

Agenda setters and comparing institutions

The veto player who can make proposals to the others first is the agenda setter. Because it can choose the outcome it likes best within the range the others will accept, the agenda setter has considerable power. Tsebelis argued that governments tend to control the agenda in parliamentary systems while legislatures tend to do so in presidential systems, and that the actual number and configuration of veto players explains policy outcomes better than the presidential–parliamentary distinction. Immergut's (1990) concept of veto points stemmed from a similar concern: she argued that health insurance reform was harder in countries with more institutional points at which interest groups could block it.

Evidence and criticism

Tsebelis (1999) reported that parliamentary democracies with more veto players produce fewer significant labor laws, and Tsebelis and Chang (2004) explained the extent of change in budget structures by the number and distance of veto players. MacIntyre (2001) argued that during the Asian financial crisis too many veto players made policy rigid while too few made it volatile, both undermining investor confidence. König, Debus and Tsebelis (2011) applied the theory to reform processes in many democracies. Critics argue that the theory underplays intraparty conflict, public opinion and the courts, and that veto players' positions are hard to measure. Even so, it remains a leading analytical tool of new institutionalist political science.

FAQ

What is veto player theory in simple terms?

It holds that the more people or groups whose agreement is needed to change a policy, and the more their views differ, the harder the policy is to change. Institutions are compared by counting actors such as presidents, chambers and coalition parties and measuring their disagreements.

Are many veto players a bad thing?

Not necessarily. Policy becomes more stable and predictable, but responding quickly to crises or passing needed reforms becomes harder. Too few veto players, on the other hand, can make policy swing frequently.

Sources reviewed: 2026-10-26

References

1. Tsebelis, G. (1995). Decision making in political systems: Veto players in presidentialism, parliamentarism, multicameralism and multipartyism. British Journal of Political Science, 25(3), 289–325. The founding article — compares regime types through one veto-player framework.
2. Tsebelis, G. (1999). Veto players and law production in parliamentary democracies: An empirical analysis. American Political Science Review, 93(3), 591–608. Tests whether more veto players mean fewer significant laws.
3. Tsebelis, G. (2002). Veto Players: How Political Institutions Work. Princeton, NJ: Princeton University Press. The definitive book — policy stability, agenda setters and applications in one place.
4. Immergut, E. M. (1990). Institutions, veto points, and policy results: A comparative analysis of health care. Journal of Public Policy, 10(4), 391–416. Veto points explain divergent health reforms — a closely related precursor concept.
5. MacIntyre, A. (2001). Institutions and investors: The politics of the economic crisis in Southeast Asia. International Organization, 55(1), 81–122. Too many or too few veto players both hurt crisis response — a U-shaped application.
6. Tsebelis, G., & Chang, E. C. C. (2004). Veto players and the structure of budgets in advanced industrialized countries. European Journal of Political Research, 43(3), 449–476. Budget structure change explained by veto players — measuring policy stability.
7. König, T., Debus, M., & Tsebelis, G. (Eds.). (2011). Reform Processes and Policy Change: Veto Players and Decision-Making in Modern Democracies. New York: Springer. An edited volume applying the theory to reform processes across democracies.