98-F-3. Martinelli, Cesar and Akihiko Matsui, "Policy Reversals: A Democratic Nixon and a Republican Clinton", January 1998.

We develop a model in which political parties but not voters are informed about which policies induce the optimal outcome for the voters. Policies can be located on the real life. Parties are policy-oriented, and have polarized preferences, i.e., any leftward move of the implemented policy is preferred by the left-wing party, and any rightward move by the right-wing party. Parties have to precommit to policy platforms before the election. We divide the equilibrium set into two classes, according to whether or not the public can infer the optimal policy from the platforms the parties choose. In every equilibrium and every individual election, the right-wing party proposes a platform that is at the right of the one proposed by the left-wing party. However, in revealing, or separating, equilibria, the policy position of the right-wing party when it gets to win the election is at the left of the one implemented by the left-wing party when it wins in turn. This result partly explains some observed electoral episodes in which the wining party is the one which seems in principle least identified with the policies wished for by the electorate.