Legisprudence Vol II, No 1 FIVE PARADOXES ON LEGAL CERTAINTY AND THE LAWMAKER Patricia Popelier * Abstract The principle of legal certainty is becoming popular as a legal tool to fight uncertainty in the legal order. At the same time the very fundaments of the principle are at issue. The transformation of the principle of legal certainty into a legal tool may lead to unrealistic expectations. In order to grasp its meaning and to understand what the principle of legal certainty can and cannot do as a legal tool, the paper aims to disentangle five paradoxes. In suggesting solutions, it focuses on the meaning of legal certainty as a principle of proper law making, directed to the authors of written laws. Keywords Legal certainty, proper law making, accessibility, legitimate expectations, judicial review A. INTRODUCTION The principle of legal certainty is fundamental in modern legal orders. Constitutional and European courts acknowledge the existence of a “principle of the certainty of the law”. 1 This principle is aimed at all branches of government. With respect to jurisdiction for example, the European Court of Human Rights emphasizes that “where the courts have finally determined an issue, their ruling * Patricia Popelier is professor at the University of Antwerp, UALS, Research Group Constitutional and Administrative Law. This is the written report of a presentation held at the IAJM Congress on Legal Certainty, Sherbrooke, Québec, Canada, 26 October 2007. I wish to thank my colleague Georges Pavlakos for advice on matters of English style. 1 See P Popelier, Rechtszekerheid als beginsel voor behoorlijke regelgeving (Legal certainty as a principle of proper law making), (Antwerp, Intersentia, 1997), 256-349 and Id, “The Role of the Belgian Constitutional Court in the Legislative Process” (2005) 26 Statute Law Review, 35-37.