A New Approach to Optimal Commodity Taxation

This paper makes a fresh attempt at characterizing optimal commodity taxes. Under the usual assumptions, an extremely simple expression for second-best commodity taxes is derived, showing tax rates as functions of observable variables only, rather than as functions of unobservable variables such as compensated cross-elasticities. The main formula is independent of special preferences and of the number of commodities. It has a simple economic meaning and could be particularly useful for empirical research. Examples and remarks on the normalization problem are provided.