Abstract: This study reverses an extremely sensitive issue and developments in tax law matters, namely the distinction between different forms of illicit. At a structural level, the concepts of tax law have specific autonomy; alternatively we see a correlation with the doctrinal elements of civil law. These shades occur in the context that tax law is dependent on the patrimonial dynamics governed by civil law. Equally, the tax behaviors are likely to have their own qualification and hence a range of differentiated consequences.

Key-words: abnormal management act, abuse of rights, simulation, fraud law