Taxation of Family Income in the Light of the Principle of Ability to Pay

The fiscal rules underlying the taxation of family income, over the years, have undergone profound changes, in line with the reform of family systems, which marked the transition from the patriarchal family, based on the figure of the pater familias, to the nuclear one, composed by partners and children. Originally, the system chosen was that of legal cumulation, consisting in the imputation to the husband, in his role as head of the family, of the income produced by the members of the family unit; following the intervention of the Constitutional Court, we passed from the principle of legal cumulation to that of decumulation, characterized by the individual (or separate) taxation of the income produced by each member of the family unit, allowing each taxpayer to see the income taxed independently product, regardless of any evaluation concerning one’s own family situation.