Political denials: The policy effect of intercameral partisan differences in bicameral parliamentary systems

Bicameralism in legislatures affects both the legislative process and partisan competition. In the United States, divided partisan control of Congress has been found to lead to interparty logrolls and increased budget deficits. In parliamentary systems, it is generally assumed that similarly divided legislatures have little effect on policy. I argue, by contrast, that party discipline means that divided control of the legislature has the opposite effect: because cooperation dilutes party labels, parties have an interest in passing and claiming credit for policy, but also in preventing their counterparts from doing the same. The result is a game in which chamber majorities balance the desire to make policy with the need to differentiate themselves from each other (to the extent that they are different). I test the hypothesis of an inverse relationship between divergence and policy making in a nine-country. TSCS regression of deficits on an index of chamber divergence.