Polarized platforms and moderate policies with checks and balances

In standard spatial models of elections, parties with policy preferences ta ke divergent positions. Their platform positions are less separated than ar e the parties' ideal policies. if policy is the result of an executive-legi slative 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 pl atforms. Consequently, divergence in platforms is greater than in the stand ard model, especially when uncertainty is high and the legislature more pow erful than the executive. For some parameters, parties may even 'posture' b y adopting platforms that are more extreme than their 'true' ideal points. (C) 2000 Elsevier Science S.A. All rights reserved.