Nonseparable Utility and the Double Dividend Debate: Reconsidering the Tax-Interaction Effect

The literature on the use of environmental taxes inthe presence of distortionary (labor) taxes warns thata partial-equilibrium Pigouvian tax analysis is notappropriate because increasing the price of dirtygoods can futher aggravate the prexisting distortions. This argument is most frequently made assuming thatlabor is taxed to meet a fixed revenue requirement.When a dirty good is also taxed, others argue thatthis lowers workers' real wages, causing people toreduce their labor supply below its already suboptimallevel, aggravating labor market distortions. However,most papers ignore the effect that a cleanerenvironment can have on labor supply. That is, mostpast work has assumed that the quality of theenvironment is weakly separable in the utilityfunction. We argue that a cleaner environment canincrease labor supply, at least partially offsettingany incentive for workers to decrease their laborsupply. Further, we show explicitly how relaxing theseparability assumption affects the standardresults.