Protection of family diversity: marriage, civil and de facto unions (cohabitation, joined families); same-sex unions and / or marriage

The constitutional complaints concerned the question of the constitutionality of the exclusion of parents living in a marital community from the right to deduct childcare costs as extraordinary burdens from the income tax assessment basis due to gainful employment, as well as from the granting of a household allowance. 
The FCC held that the parental duty to bring up children under Article 6.2.1 of the Basic Law requires parents to cover the economic needs of the children through benefits in kind as well as to ensure care and education. From Article 6.1 of the Basic Law arises the right to decide freely which parental responsibility is exercised and also the involvement of a third party. At the same time, Article 6.1 of the Basic Law guarantees a special principle of equality, which prohibits the discrimination of marriage and the family in relation to other cohabiting and child-raising communities, also with regard to tax relief. 
The principle of equal taxation requires that taxes be levied in accordance with financial capacity, which is reflected in the legislative obligation to exempt from taxation income that is needed to ensure a family's minimum subsistence level. 
In this context, parents' ability to pay is generally reduced by the child's need for care as a component of the child-related subsistence minimum, irrespective of the type of demand coverage. It is one of the state's tasks to recognize and enable childcare in the form chosen by the parents. 
By allowing the deduction of childcare costs for "single" taxpayers, § 33c of the Income Tax Act violated the complainants' right to equal treatment under Article 6.1 and 2 of the Basic Law. In accordance with the provision of § 33c.2 of the Income Tax Act, only parents with unlimited tax liability and living in a marital community were excluded from the tax relief.
The same applied to the regulation on the deduction of a household allowance. Non-marital parental unions were granted such a tax-free allowance even if each parent is entitled to a basic tax-free allowance, while spouses were generally deprived of it.