Conclusions and theses

pp. 499-520

in: Humberto Ávila, Certainty in law, Berlin, Springer, 2016

Abstract

Legal certainty is a normative ideal of the first magnitude in any legal order, and particularly in the Brazilian order. Its importance is even greater in the field of tax law: The ideals protected by legal certainty have special relevance in the tax subsystem and a more protective significance by virtue of the existence of specific and emphatic norms in the National Tax System that act as instruments to guarantee the intelligibility of law through via the determinability of incidence hypotheses (the legality rule and the system of competence rules), the reliability of law through stability over time (the rule restricting the regulation of prescription and limitation to supplementary laws), period of validity (the rule prohibiting retroactivity) and procedure (rules that expressly apply rights and guarantees not specified in the tax subsystem, such as protection for acquired rights, completed legal acts and res iudicata), and the calculability of law through non-surprise (the anteriority rule).