Competitive Nonlinear Taxation and Constitutional Choice

In an economy where agents are characterized by different productivities (vertical types) and different abilities to move (horizontal types), we compare a unified nonlinear optimal taxation schedule with the equilibrium taxation schedule that would be chosen by two competing tax authorities if the same economy were divided into two States. The overall level of progressivity and redistribution is unambiguously lower under competitive taxation than under unified taxation; the “rich” are always in favor of competing authorities and local governments, whereas the “poor” are always in favor of unified taxation. The constitutional choice between fiscal regimes depends on the preferences of the middle class, which in turn depend on the initial conditions in terms of the distribution of abilities (incomes), the relative power of the various classes, and mobility costs. In particular, as mobility increases, it becomes increasingly likely that a reform in the direction of unification of fiscal policies in a federation will receive majority support, while a decreased average wealth can have the opposite effect