Tax law is often uncertain. In particular, the use of tax shelters tends to be in the “grey area” between illegal tax evasion and legal tax avoidance. In this paper I show that uncertainty in tax law can help achieve higher efficiency than allowing or disallowing a tax shelter with...

We analyze how a country pursuing a unilateral climate policy may contribute to a reduction in global CO2 emissions in a cost-effective way. To do so its system of energy taxes and subsidies must account for leakage of emissions from the domestic to the foreign economy. We focus on leakage...

We solve the non-linear income tax program for a rank-dependent social welfare function à la Yaari, expressing the trade-off between size and inequality using the Gini or related families of positional indices. The key idea is that when agents optimize and absent bunching, ranks in the actual...

We show how normative standpoints determine optimal taxation of wealth. Since wealth is not equal to capital, we find very different welfare implications of land rent-, bequest- and capital taxation. It is mainly land rents that should be taxed. We develop an overlapping generations model with...

We propose and axiomatically characterize a family of welfare criteria that prioritize individuals making larger sacrifices. By combining efficiency with a concern for equality of sacrifice, our criteria avoid serious shortcomings of utilitarianism. We illustrate our results within the...

We consider optimal non-linear income tax problems when the social welfare function only depends on ranks as in Yaari (1987) and weights agree with the Lorenz quasi-ordering. Gini, S-Gini, and a class putting more emphasis on inequality in the upper part of the distribution belong to this set....

Most governments will have to raise additional resources to deal with the aftermath of the corona crisis. This paper argues that excise duties on drinking, smoking, gambling, sugar-sweetened beverages, plastics, fossil fuels, motoring, telecoms and platforms are the preferred instruments. In...

There is increasing empirical evidence that people systematically differ in their rates of return on capital. We derive optimal non-linear taxes on labor and capital income in the presence of such return heterogeneity. We allow for two distinct reasons why returns are heterogeneous: because...

The objective of this paper is to critically assess the use of simple rules for the social cost of carbon (SCC) that employ a rudimentary form of the Ramsey Rule. Two interrelated caveats apply. First, if climate change poses a serious problem, it is hard to justify an exogenous constant growth...

I study the optimal taxation of robots and labor income. In the model, robots substitute for routine labor and complement non-routine labor. I show that while it is optimal to distort robot adoption, robots may be either taxed or subsidized. The robot tax exploits general-equilibrium effects to...