OS ECJ-TF 3/2015 on the Decision of the European Court of Justice in C.G. Sopora (Case C-512/13), on 'Horizontal Discrimination'

This article deals with the decision taken by the Court of Justice of the European Union in Sopora (Case C-512/13), which was decided by the Grand Chamber of the ECJ on 24 February 2015. It concerns the question of whether a specific requirement to obtain a tax advantage for foreign (incoming) workers violates the freedom of movement of workers (Art. 45 TFEU). This case prominently raises the issue of a differentiation not between nationals and non-nationals (i.e., "vertical discrimination"), but rather between different non-nationals (i.e., "horizontal discrimination") in the context of the taxation of payments of deemed employment expenses ("extraterritorial costs"). By clearly accepting such "horizontal comparison" in the context of Art. 45 TFEU, it resolves a question where the Court "up to now" has "given varying signals". It also suggests that the Court's answer to that question might have wider application