Public Good Provision Financed by Nonlinear Income Tax Under Reduction of Envy

We examine optimal taxation and public good provision by a government which takes reduction of envy into consideration as one of the constraints. We adopt the notion of extended envy-freeness proposed by Diamantaras and Thomson (1990), called λ-equitability. We derive the modified Samuelson rule at an optimum income tax, and show that, using a constant elasticity of substitution utility function, the direction of distorting the original Samuelson rule to relax λ envy free constraints is crucially determined by the elasticity of substitution. Furthermore, we numerically show that the level of public good increases (or decreases) in the degree of envy-freeness when the provision level is upwardly (or downwardly) distorted