We develop a general method to study the effects of non-linear taxation in dynamic settings using variational arguments. We first derive general theoretical formulas that characterize the welfare effects of local tax reforms and, in particular, the optimal tax system, potentially restricted...

The Mirrlees Review recommends that commodity taxation should in general be uniform, but with some goods consumed in conjunction with labour supply (such as child care) left untaxed. This paper examines the validity of this claim in an optimal income tax framework. Contrary to the recommendation...