Rules, ideology and coalition formation in the European Parliament: past, present and future

This research investigates the frequent creation of voting coalitions between the Socialist (PSE) and largely Christian Democratic (PPE) party groups within the European Parliament. The tendency of the PPE and PSE to form a 'grand coalition' is frequently understood to imply that there is no significant role for ideology in the European Parliament. Two common explanations of the creation of the 'grand coalition' are tested demonstrating their inability to adequately explain actual coalition trends. The author then offers some simple spatial models as a means of predicting when we should expect to see the grand coalition form. She then analyzes 200 votes to test for the existence of each of the theoretical models and discusses the present and future role of ideology within the European Parliament.