The Double Majority Principle and Decision Making Games in Extending European Union

In this paper game-theoretical concepts of power indices are applied to evaluation of power (or influence) distribution among different European Union member states in a decision making processes in the Council of Ministers, Commission and European Parliament. Dynamics of distribution of power during a sequence of extensions is analyzed and possible consequences of future East European and Mediterranean extensions anticipated. A new voting rule concept is suggested and evaluated: the so called double majority principle, based on two sets of weights in voting: one given by the number of votes in a decision making body and the second by the proportion of GDP or proportion of population. Models of Commission, Council, and European Union interactions are investigated from the point of view of power distribution among the member states and among the three most important European institutions.