摘要：THECommonwealth government's forthcoming proposals to reform Austra-lia's taxation system could well include the introduction of a goods and ser-vices tax (GST). This would be a broad-based consumption tax that may either be hidden in the price of goods or, as in Canada, added on explicitly at the point of sale. Political considerations are likely to play a major role in the choice of modifica-tions to specific taxes. For example, voters may be concerned only with the total tax paid, along with the total amount of government services provided (and, possibly, associated changes in government debt if revenues and expenditures do not bal-ance). In this case, tax reform that increases the efficiency of the tax system and is revenue-neutral, as the government of Canada claimed of its GST when it was in-troduced in 1991,1should not affect the government's electoral chances. However, if voters do not treat all types of taxes as being indistinguishable, then there are dif-ferent politicalcosts associated with alternative types of taxes and these may differ substantially from the economic costs of these taxes. To the extent that different forms of taxes affect voters differently, governments may choose those tax instru-ments which have lower political costs rather than those that have lower economic costs. As noted by Hettich and Winer (1984), the politically optimal tax structure is one in which the marginal politicalcost, rather than the marginal economic cost, of raising an additional dollar of tax revenue is the same for all types of taxes
