The article argues that the relationship between accounting and taxation in each country and in relation to a given item of income is a matter of juridical interpretation, with important consequences for the determination of the taxable basis. Furthermore, it contends that current analytical classifications of the relationship between taxation and accounting do not cover all possibilities. Such conclusions are drawn from the analysis of the issue of fiscal amortization of goodwill paid on business combinations, in Brazil. First, the article analyses theoretical models that aim at describing relations between taxation and accounting. Then, it exposes Brazilian legislative changes that have led to litigation concerning fiscal amortization of goodwill. The article examines four interpretive positions that deal with the interactions between accounting and taxation concerning goodwill amortization in Brazil, all based on the search for the substantive justification of the tax rule. Apart from the more general conclusions regarding the nature of the relationship between accounting and taxation, the article also concludes that the model of justification that has been used in Brazil is not sufficient and that the principle of legal certainty can play a significant role.
Intertax