Political dynamics, public goods and private spillovers

Positive and negative spillovers from private activities onto aggregate economic outcomes are empirically significant. How might politics interact with private investment incentives and their externalities? Our theory connects politics to policies which distort private spillovers. This has implications for empirical identification. In our model, for large negative externality there is a unique equilibrium with perpetually high tax rates and majority poor voters. This is a consequence of political manipulation that anticipates private spillovers on forward-looking investment decisions. When positive spillovers are sufficiently large, individuals can coordinate on policies that encourage private investment. This sustains an equilibrium with perpetually low tax rates and majority rich voters. The resulting multiple equilibria can be used to interpret existing conundrums in empirical findings. We can also rationalize an observed cross-country empirical regularity in terms of public funding for knowledge goods and income inequality.