by Rasmus Smith Nielsen, PhD student The article concludes that the Danish Supreme Court in its judgment UfR 2017.824H (Ajos case) has ruled that 1) an application of the general EU principle prohibiting discrimination on grounds of age in Denmark together with 2) direct effect and horizontal effect of article 21 in the Charter on Fundamental Rights of the European Union and 3) direct effect of law derived from TEU art. 6, section 3, would under e.g. the Danish EU accession law constitute an infringement of art. 88 of the Danish Constitution (amendment of the constitution), and 4) the European Court of Justice has according to the Danish Supreme Court, at least, before 1th December 2009 infringed the treaty (currently TEU and TFEU), cf. e.g. TEU art. 5, section 2, TEU art. 13, section 2, and TFEU art. 352.