Case C-378/17: Judgment of the Court (Grand Chamber) of 4 December 2018 (request for a preliminary ruling from the Supreme Court — Ireland) — Minister for Justice and Equality, Commissioner of An Garda Síochána v Workplace Relations Commission (Reference for a preliminary ruling — Equal treatment in employment — Directive 2000/78/EC — Prohibition of discrimination on grounds of age — Recruitment of police officers — National body established by law in order to ensure enforcement of EU law in a particular area — Power to disapply national legislation that conflicts with EU law — Primacy of EU law)