Optimal income taxation with human capital accumulation and limited record keeping

This paper characterizes optimal income taxes in a dynamic economy where human capital is unobservable and the government is restricted to use taxes that depend only on current income. I show that unobservability of human capital tends to decrease the labor wedge, while the effect on the human capital wedge is uncertain. I also analyze the relationship between optimal taxes in economies with and without endogenous human capital and identify two qualitative reasons why the optimal tax codes will differ. I perform numerical simulations to calculate the quantitative relevance of endogenous human capital formation for optimal tax policy. I find that endogenous human capital lowers marginal tax rates by about 9% on average, as compared with a static model without human capital.