The German constitution of 1949 does not define a tax. The Federal Constitutional Court initially pointed to the reception of the traditional, purely fiscal notion of a tax from the Reich Tax Code of 1919 for the purposes of the constitution. Later, the court recognised as “taxes in the constitutional sense” also taxes of steering and stimulating nature, which started a discussion in the doctrine and, over time, the correction of the statutory definition in the new Tax Code of 1977. The doctrine also creates its definitions. The practical significance of statutory and doctrinal definitions is limited. The most important role is played by the constitutional concept. Its content determines the distribution of financial competences between the...