Neither the Treaty of Rome nor the other fundamental Treaties instituting the European Community and Union contain specific rules on the procedure to be followed during tax reassesment. There are specific provision related to the findamental rights to be respected on freedom to be saveguarded from the intridive activity of the Tax Office at the research of evidence on a possible tax evasion. The reason is the priority tha tyhe Founding fathers attributed to the substantive aspects of taxation, particilarly for what concerns value added tax and customs duties. This loophole has been intragrated in teh recent years both bt the ECJ case law, and even more recetnly by a case of the European Court on Human Rights and fundamental freedoms. In the precedent Ravon the latter ruled that Article 6 of the ECHR is applicable to tax procedureas as well, if some conditions are met. This precedent is of fundamental importance in theory of taxation because it seems at forst glance to overtake to taboos of the European case law, the impossibility to apply the due process caluse to tax processes and the possibility to extend the latter rule to a phase preceding the process, and therefore not manged by an impartial judge.