Taxation of Mobile Factors as Insurance under Uncertainty

This paper considers the effects of the taxation of mobile factors, i.e., capital, under uncertainty. The wages earned by residents of a jurisdiction are uncertain due to random shocks. Since the uncertain wages in a jurisdiction depend on the amount of mobile capital employed in the jurisdiction, and since taxation alters the quantity of capital employed, taxation affects the riskiness of uncertain wages. In particular, the taxation of capital moderates the fluctuation of uncertain wages, thereby providing insurance. For this reason, jurisdictions use distortionary capital taxation even if lump‐sum taxation is available. In addition, this insurance effect counteracts the tendency toward too low tax rates on capital arising from tax competition, and possibly improves the efficiency of tax competition.