Political competition within and between parties: an application to environmental policy

This paper presents a political economy model that explains the low rate of emission taxes in the U.S., as well as the fact that neither Democrats nor Republicans propose to increase them. The voters differ according to their wage and capital incomes which are assumed to have a bivariate lognormal distribution. They vote over the emission tax rate and a budgetary rule that specifies how to redistribute the tax proceeds. The political competition is modeled à la Roemer (2001) where the two parties care for the policies they propose as well as the probability of winning; the equilibrium solution concept is the Party Unanimity Nash Equilibrium (PUNE). We calibrate the model using U.S. data and compute the PUNEs numerically. Two main results emerge. All "viable" PUNEs entail subsidies on emissions (as opposed to taxes). This indicates the importance of distributional concerns in garnering political support for environmental policies. Second, parties always propose an interior value for the budgetary rule even though all citizens prefer extreme values. This illustrates the emergence of political compromise to attract voters.