Abstract

In parliamentary systems, legislative parties are the building blocks for executive coalitions. A standard assumption in the large literature on coalition politics is that legislative parties form fixed units from one election to the next. Under some conditions, however, this assumption falls flat. For instance, about one-fourth of legislators in the Italian lower house switched parties between 1996 and 2001. How is legislative party switching linked to the politics of executive coalitions? This paper examines how government composition affects the direction of party switching, and how party switching affects the reallocation of cabinet office. I devote in-depth scrutiny to Italy. Subsidiary country cases, chosen to maximize institutional variation, are Australia, Britain, Canada, France, and Spain