We develop a model of policy experimentation in federal systems in which heterogeneous districts choose both whether to experiment and the policies to experiment with. The prospect of informational spillovers implies that in the first best the districts converge in their policy choice....

A club's majority rule defines the number of members that must approve a policy proposed to replace the status quo. Since the majority rule thus dictates the extent to which winners must compensate losers, it also determines the incentives to invest in order to become a winner of anticipated...