Public Choice

, 141:17 | Cite as

A behavioral power index

  • Serguei Kaniovski
  • Dennis Leech


We propose an empirically informed measure of the voting power that relaxes the assumptions of equally probable and independent votes. The behavioral power index measures the voter’s ability to swing a decision based on the probability distributions of the others’ behavior. We apply it to the Supreme Court of the United States using roll-call data to estimate voting probability distributions, which lead us to refute the assumption of equally probable and independent votes, and estimate the equivalent number of independent Justices for the Warren, Burger and Rehnquist benches, which turns out to be very low.


Behavioral voting power Constitutional voting power U.S. Supreme Court 

JEL Classification



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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Austrian Institute of Economic Research (WIFO)ViennaAustria
  2. 2.Department of EconomicsUniversity of WarwickCoventryUK

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