We examine preferences for income and wealth taxation in Germany and how they interact within the tax system. In a large-scale online experiment, 1,691 participants are randomly assigned to state either an unspecified overall tax burden, separate income and wealth tax burdens, an income tax burden only, or a wealth tax burden only. Average (implicit marginal) preferred tax rates are 17.4% (18.9%) for income and 4.1% (2.3%) for wealth. When no explicit wealth tax is available, preferred income tax rates are approximately 30% higher, indicating that respondents associate wealth with an ability-to-pay taxes. When both instruments are available, however, respondents do not treat them as substitutes. Instead, they combine both tax burdens rather additively, yielding a substantially higher overall tax burden. Political and redistributive attitudes explain further heterogeneity. Respondents also appear to exempt low levels of wealth and favor taxing financial assets and real estate other than the primary residence.

Horizontal inequity occurs when employees and self-employed with the same income end up with different effective tax burdens, due to the difficulty of enforcing taxes on self-employed. Based on detailed micro-tax simulations models integrated with household surveys in 25 developing countries, we find that tax systems incur large horizontal inequities in practice and that reforms which improve vertical equity worsen horizontal equity by the same amount. An in-person survey in Pakistan and online surveys across multiple countries reveal widespread concern about horizontal equity. Randomized information treatments heighten the concern but do not shift tax preferences over horizontal versus vertical equity.

Economists design schemes to finance environmental policies based on efficiency, but voters, whose support determines the feasibility of such schemes, hold beliefs about efficiency and fairness that often collide with economic theory. We design a large-scale information experiment to assess a representative population’s beliefs about alternative financing schemes. Informed consumers support a CO2 tax after learning the rich pollute more, but oppose it and do not oppose government deficits when learning older people also pollute more. When learning that certain groups, due to luck, gain from climate change, consumers oppose redistribution from gainers to losers. Everybody despises market solutions such as private insurance. Consumers’ beliefs could lead to inefficient schemes to finance environmental policies but communication can manage consumers’ beliefs about the desirability of alternative schemes.