Direct Versus Indirect Taxation: The Design of the Tax Structure Revisited

This article studies the optimal direct/indirect tax mix problem when individuals differ in several unobservable characteristics (productivity and endowments). It presents general expressions for the optimal commodity tax rates and proves that contrary to Atkinson and Stiglitz's (1976) result, differential commodity taxation remains a useful instrument of tax policy even if preferences are separable between labor and produced goods. When cross substitution effects are zero, the expressions resemble traditional many households Ramsey rules. In a Cobb–Douglas illustration, where endowments differ only in good 1 (interpreted as “wealth”), the tax on good 2 provides an indirect way to tax the unobservable wealth.     

Optimal Commodity Taxes in Australia

The recent changes to commodity taxes in Australia have led to renewed interest in a classic question in public finance: should the tax rates be uniform or differentiated? This article attempts to answer this question by calculating optimal commodity taxes in Australia for a nine‐item disaggregation. The estimates point to non‐uniform commodity taxes, even from the viewpoint of an inequality‐insensitive tax planner. The optimal commodity taxes bear little resemblance with the pre‐GST or post‐GST tax rates. No less significant is our observation that even the purely efficiency‐driven optimal commodity taxes imply lower real expenditure inequality than the actual taxes.     

Tax Competition in Vertically Differentiated Markets with Environmentally Conscious Consumers

This paper analyses the effects of tax competition on environmental product quality, pollution and welfare in a two-country, vertically differentiated, international duopoly, in which consumers are environmentally conscious. The firm in each country chooses first the environmental quality of its product (which reflects the emissions generated in the production process) and then the price. In equilibrium one country will be more polluted than the other because firms choose different levels of environmental quality of their products. We find that a country’s optimal commodity tax is higher if the domestic firm is the more polluting supplier. Furthermore, non-cooperative commodity tax rates are inefficiently high in equilibrium. This is because, in this framework with environmentally aware consumers, commodity taxes affect the choice of firms regarding their emissions. Therefore, a domestic tax reduction not only raises the profits of the foreign firm but also lowers its emission levels, resulting in higher welfare for the other country. We also analyse the optimal cooperative and non-cooperative commodity and emission taxes with border tax adjustments. With these two policy instruments available, commodity taxes are higher.     

Is commodity taxation unfair?

In a model where agents have unequal skills and heterogeneous preferences about consumption goods and leisure, this paper studies how to combine commodity taxes and non-linear income tax. It proposes a particular social welfare function on the basis of fairness principles. It then derives a simple criterion for evaluating the social welfare consequences of various tax schedules. Under the proposed approach, the optimal tax should have no commodity tax for some range of consumptions, and income redistribution would feature high subsidies to the working poor. It is also shown that, even when the income tax fails to be optimal, commodity taxes may not improve social welfare.     

Optimal taxation, global externalities and labor mobility

This paper concerns transboundary environmental problems in the context of an optimal tax model. We assume that part of the labor force is mobile across countries, and that the set of tax instruments includes a nonlinear income tax and a commodity tax on the ‘dirty’ good that is causing damage to the environment. The purpose is to compare the (globally optimal) second best policy of a cooperative equilibrium with the policy implicit in a noncooperative equilibrium. We show that the commodity taxes differ between equilibria because of: (i) transboundary externalities not internalized by national governments, (ii) interaction effects between environmental and other policies, and (iii) labor mobility.     

Reexamination of Economic Growth, Tax Policy, and Distributive Politics

The paper examines the relationship between economic growth, tax policy, and distribution of capital and labor ownership in a one‐sector political‐economy model of endogenous growth with productive government spending financed by a proportional tax on capital income. The analysis shows that inequality in wealth and income can be positively or negatively related to the optimal tax rate. In either environment, higher inequality leads to a lower after‐tax return to capital, thereby reducing the economy's growth rate.     

The optimal taxation of risky capital income: An elasticity rule

Should risky capital income be taxed like safe income or should tax rates be differentiated? The question is analyzed in a 2-assets model of portfolio choice. Flat tax rates are chosen in order to maximize the investor's expected utility from terminal wealth subject to an expected tax revenue constraint. If lump-sum taxes are not available, optimal tax rates are characterized by an elasticity rule: The relative change in the risk remuneration should be equal to the inverse of the product of two elasticities. One is the output elasticity of capital. The other is the demand elasticity for risky investments with respect to a revenue preserving tax variation.     

Optimal taxation with consumption time as a leisure or labor substitute

This paper studies the optimal commodity taxation problem when time taken in consumption is a perfect substitute for either labor or leisure. It shows that while labor substitutability affects the optimal tax structure, leisure substitutability leaves the classical optimal tax results intact. In the Ramsey tax framework with linear income taxes, whether the consumers have the same or different earning abilities, labor substitutes tend to be taxed at a higher rate than leisure substitutes with the tax differential being increasing in consumption time. This is not necessarily the case when one allows for nonlinear income taxation.     

Externalities and optimal taxation

This paper reexamines the optimal tax design problem (income and commodities) in the presence of externalities. The nature of the second–best, and the choice of the tax instruments, are motivated by the informational structure in the economy. The main results are: (i) environmental levies (linear or nonlinear) differ in formula from Pigouvian taxes by the expressions for the optimal tax on private goods; (ii) externalities do not affect commodity tax formulas (linear and nonlinear) for private goods; (iii) externalities do not affect the income tax structure if commodity taxes are nonlinear and affect it if commodity taxes are linear; and (iv) a general income tax plus strictly Pigouvian taxes are sufficient for efficient taxation if individuals of different types have identical marginal rates of substitution (at any given consumption bundle).     

Trade,environment, and income inequality: An optimal taxation approach

In a small open economy, how should a government pursuing both environmental and redistributive objectives design domestic taxes when redistribution is costly? And how does trade liberalization affect the economy's levels of pollution and inequalities, when taxes are optimally and endogenously adjusted? Using a general equilibrium model under asymmetric information with two goods, two factors (skilled and unskilled labor), and pollution, this paper characterizes the optimal mixed tax system (nonlinear income tax and linear commodity and production taxes/subsidies) with both production and consumption externalities. While optimal income taxes are not directly affected by environmental externalities, conditions are derived under which under‐ or over‐internalization of social marginal damage is optimal for redistributive considerations. Assuming that redistribution operates in favor of the unskilled workers and that the dirty sector is intensive in unskilled labor, simulations suggest that trade liberalization involves a clear trade‐off between the reduction of inequalities and the control of pollution when the source of externality is only production; this is not necessarily true with a consumption externality. Finally, an increase in the willingness to redistribute income toward the unskilled results paradoxically in less pollution and more income inequalities.     

On optimal redistributive capital taxation

This paper addresses conflicting results regarding the optimal taxation of capital income. Judd proves that in a steady state, there should be no taxation of capital income. Lansing studies a logarithmic example of one of Judd's models and finds that the optimal steady‐state tax on capital income is not always zero—it is positive in some specifications and negative in some others. There appears to be a contradiction. However, I show that Lansing derives his result by relaxing the convergence hypotheses of Judd's theorem. With less restrictive hypotheses, a wider range of primitives (parameter values, initial condition, etc.) satisfy the hypotheses and because each specification of primitives generates its own optimal time path(s) for the model's variables, it follows that a wider range of time paths with a wider range of steady‐state properties is possible. This raises a question. What happens if the convergence hypotheses are weakened further so that they are satisfied by a wider yet range of primitives? I find that at any interior steady state for the model's optimal tax equilibrium, either the capital tax is zero or else the elasticity of marginal utility is unitary which is satisfied identically in Lansing's log example. In effect, Lansing's example illustrates the only way in which an interior steady state can violate the zero tax result.     

Poverty alleviation and tax policy

This paper examines public good provision and tax policy—optimal non-linear income taxation and linear commodity taxation—when the government departs from purely welfarist objective function and seeks to minimise poverty. This assumption reflects much policy discussion and may help understand some divergences of practical tax policy from lessons in optimal tax analysis. In contrast to Atkinson and Stiglitz (J. Public Econom. 6 (1976) 55), it may be optimal to use differentiated commodity tax rates, including the taxation of savings, even if preferences are separable in goods and leisure. The optimal effective marginal tax rate at the bottom of the distribution may be negative, suggesting that wage subsidy schemes can be optimal. Finally, optimal provision of a public good is analysed under poverty minimisation.     

On the undesirability of commodity taxation even when income taxation is not optimal

An important result due to Atkinson and Stiglitz (1976) [Atkinson, A.B., Stiglitz, J.E., 1976. The design of tax structure: Direct versus indirect taxation. Journal of Public Economics 6, 55–75.] is that differential commodity taxation is not optimal in the presence of an optimal nonlinear income tax (given weak separability of utility between labor and all consumption goods). This article demonstrates that this conclusion holds regardless of whether the income tax is optimal. In particular, given any commodity tax and income tax system, differential commodity taxation can be eliminated in a manner that results in a Pareto improvement. Also, differential commodity taxation can be proportionally reduced so as to generate a Pareto improvement. In addition, for commodity tax reforms that neither eliminate nor proportionally reduce differential taxation, a simple efficiency condition is offered for determining whether a Pareto improvement is possible.     

Optimal Tax Policy under Environmental Quality Competition

This paper studies the socially optimal emission and commodity tax policy when consumers are willing to pay a price-premium for environmentally friendlier variants of a commodity vertically differentiated in environmental quality. The first-best levels of quality can be obtained by a combination of a uniform ad valorem tax and an emission tax (or a subsidy for buying green products). The first-best emission tax is higher than the social valuation of the positive externality associated with average environmental quality. Regardless of environmentally conscious consumers, if only one instrument is available, the second-best emission tax is equal to the social valuation of the positive externality associated with average environmental quality. A uniform ad valorem tax increases welfare only if the social valuation of the positive externality associated with average environmental quality is low enough.     

SOME EMPIRICAL EVIDENCE ON DEMAND SYSTEM* AND OPTIMAL COMMODITY TAXATION

We have two major tasks in this paper. The first is to obtain a reasonable estimate of the Japanese demand system, which includes leisure, income and commodity choices. The second is to compute and evaluate the optimal tax equilibrium. The estimation result, based on the Almost Ideal Demand System, is found to be consistent with the microeconomic theory. We evaluate the optimal commodity tax structure by calculating the equilibria under lump‐sum, optimal commodity and uniform commodity taxation schemes. The deadweight losses under uniform taxation are very small, and the optimal commodity tax rates are strikingly close to uniform.     

On the optimal taxation of two person households

This paper generalises the optimal commodity tax formulae for households containing one person to cover the empirically relevant case of two person households. We provide an appropriate framework for the empirical estimation of the optimal tax structure and argue that this may be largely determined by female labour supply behaviour.     

Conjectural Variations, Market Power, and Optimal Trade Policy in a Vertically Related Industry

The paper introduces the conjectural variations and bargaining approaches into a vertical model wherein a foreign upstream firm supplies one input to two downstream firms that produce differentiated products for the export market. Various downstream firms’ competition modes and upstream's pricing schemes emerge as special cases of this formulation. The authors show that the optimal export policy of a downstream country depends crucially on the downstream firms’ conjectures of rivals’ responses, the upstream firm's pricing schemes, their relative bargaining powers, and the degree of product differentiation. If the upstream's pricing or bargaining power is strong (weak) and if the downstream's degree of competition is high (low), a tax (subsidy) is optimal owing to a strong (weak) vertical profit‐shifting effect and a weak (strong) horizontal effect.     

Audit Probability versus Effectiveness: The Beckerian Approach Revisited

The Beckerian approach to tax compliance examines how a tax authority can maximize social welfare by trading‐off audit probability against the fine rate on undeclared tax. This paper offers an alternative examination of the privately optimal behavior of a tax authority tasked by government to maximize expected revenue. The tax authority is able to trade‐off audit probability against audit effectiveness, but takes the fine rate as fixed in the short run. I find that the tax authority's privately optimal audit strategy does not maximize voluntary compliance, and that voluntary compliance is nonmonotonic as a function of the tax authority's budget. Finally, the tax authority's privately optimal effective fine rate on undeclared tax does not exceed two at interior optima.     

Optimal Capital Taxation in a Neoclassical Growth Model

This paper studies the optimal factor tax incidence in a neoclassical growth model with a given share of government expenditure in output. In the Ramsey planner's optimization, the effect of next period's capital on government expenditure equals the given share of the marginal product of capital. Capital accumulation reduces the discounted net marginal product of next period's capital by way of increasing government expenditure. In order to internalize the distortion, it is optimal to tax capital income in the long run.     

On Optimal Commodity Taxes When Consumption Is Time Consuming

This paper studies the problem of optimal taxation of commodities when consumption is a time‐consuming activity. This is done under two distinct preference separability assumptions: between goods and labor supply, and between goods and leisure. It argues that with the labor separability, the traditional uniform taxation results of optimal tax theory continue to hold. With leisure separability, on the other hand, consumption time is a major ingredient of optimal tax rates. However, the relationship between consumption time and optimal tax rates depends crucially on the representation of the economy. In representative consumer economies, time differences determine the pattern of optimal tax rates so that goods whose consumption take more time are subjected to higher tax rates. When individuals have different earning abilities, redistributive, incentive, and efficiency considerations also come into play resulting in a complex relationship. The paper derives formulas for optimal commodity taxes in this case on the basis of three different tax structures: linear commodity taxes in combination with linear and nonlinear income taxes, and nonlinear commodity taxes in combination with nonlinear income taxes.