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	Veto Player Analysis	Spatial Voting Model
Field	Political Science	Political Science
Family	MCDM	MCDM
Year of origin	1995	1957
Originator	George Tsebelis	Harold Hotelling, Duncan Black & Anthony Downs
Type	Comparative institutional analysis framework	Formal model of electoral and legislative choice
Seminal source	Tsebelis, G. (2002). Veto Players: How Political Institutions Work. Princeton University Press. ISBN: 9780691091891	Downs, A. (1957). An Economic Theory of Democracy. Harper & Row. ISBN: 9780060417505
Aliases	Veto Players Theory, Veto Points Analysis, Tsebelis Veto Player Framework, Policy Stability Analysis	Spatial Theory of Voting, Downsian Model, Proximity Voting Model, Median Voter Model
Related	4	4
Summary	Veto player analysis is a spatial-institutional framework, developed by George Tsebelis in his 1995 article and 2002 book, for predicting the capacity of a political system to change policy. A veto player is any individual or collective actor whose agreement is required to alter the status quo. The theory shows that the potential for policy change shrinks as the number of veto players grows, as the ideological distance between them widens, and as their internal cohesion increases — three structural variables that together determine a system's policy stability independently of constitutional labels such as presidentialism or parliamentarism.	The spatial voting model represents voters and political alternatives as points in a common geometric policy space and assumes that each voter supports the alternative nearest to their own ideal point. Rooted in Hotelling's location theory, Duncan Black's 1948 single-peakedness result, and Anthony Downs's 1957 economic theory of democracy, the model yields two foundational results: the median voter theorem, which identifies the equilibrium policy in one dimension, and the Downsian prediction that two vote-seeking parties converge toward the center. It is the workhorse formalism behind modern empirical estimation of political positions.