On Indeterminacy and Growth under Progressive Taxation and Utility-Generating Government Spending

We examine the theoretical interrelations between progressive income taxation and macroeconomic (in)stability in an otherwise standard one-sector AK model of endogenous growth with utility-generating government purchases of goods and services. In sharp contrast to traditional Keynesian-type stabilization policies, progressive taxation operates like an automatic destabilizer that generates equilibrium indeterminacy and belief-driven fluctuations in our endogenously growing macroeconomy. This instability result is obtained regardless of (i) the degree of the public-spending preference externality, and (ii) whether private and public consumption expenditures are substitutes, complements, or additively separable in the household's utility function.