After enlargement: Voting patterns in the sixth European parliament

We examined how voting behavior in the European Parliament changed after the European Union added ten new member-states in 2004. Using roll-call votes, we compared voting behavior in the first half of the Sixth European Parliament (July 2004 - December 2006) with voting behavior in the previous Parliament (1999-2004). We looked at party cohesion, coalition formation, and the spatial map of voting by members of the European Parliament. We found stable levels of party cohesion and interparty coalitions that formed mainly around the left-right dimension. Ideological distance between parties was the strongest predictor of coalition preferences. Overall, the enlargement of the European Union in 2004 did not change the way politics works inside the European Parliament. We also looked at the specific case of the controversial Services Directive and found that ideology remained the main predictor of voting behavior, although nationality also played a role.