Polarized platforms and moderate policies with checks and balances

In standard spatial models of elections, parties with policy preferences take divergent positions. Their platform positions are less separated than are the parties' ideal policies. if policy is the result of an executive-legislative compromise, the policy preferences of the parties can be moderated by voter behavior. Divided government may result. Since parties anticipate the moderated outcomes, they have an added incentive to choose separated platforms. Consequently, divergence in platforms is greater than in the standard model, especially when uncertainty is high and the legislature more powerful than the executive. For some parameters, parties may even 'posture' by adopting platforms that are more extreme than their 'true' ideal points. (C) 2000 Elsevier Science S.A. All rights reserved.