Investment in public infrastructure with spillovers and tax competition between contiguous regions

Two contiguous regions compete to attract a population of heterogeneous firms. They choose infrastructure levels in a first stage and compete in taxes in a second stage. We study the properties of Subgame Perfect Nash equilibria in this stage game depending on the extent to which the benefits of infrastructure spill over from one region to the other. First, we show that the presence of inter-regional spillovers allows jurisdictions to control for the intensity of tax competition and therefore affects the optimal levels of infrastructure selected at equilibrium. Second, by comparing the non-cooperative and cooperative outcomes, we show that the extent to which regions overinvest in infrastructures negatively depends on the intensity of the spillovers.