On the difficulty of making decisions within the EU-25

In this paper we measure the effect of the quota on the difficulty of making decisions in the EU-25 Council with the weights agreed upon in the Treaty of Nice. We compute the probability of a proposal being rejected in the Council. This probability depends on the voting rule (and therefore on the quota) and on the probabilities of the different vote configurations. Here we do not consider that all vote configurations are equiprobable, the classical implicit or explicit assumption in the literature. We assume that vote configurations with a minority of member states in favour of the proposal have a null probability, with other vote configurations being equiprobable.