(b) Sunset clauses can tackle uncertainty
Legal certainty is often presented as a synonym of continuity of lasting legislation due to the belief that law tends towards greater certainty. However, as time goes by, the effectiveness of a rule may diminish due to the evolution of social circumstances; the discovery of new elements or information; the emergence of new complex conducts; or the consequent creation of room for novel legal disputes that were not originally comprehended by its scope. In addition, the deterrent effect of rules may equally diminish as potential litigants discover ways to readjust their conduct in order to avoid the application of this specific rule. This increasing reduction of the effectiveness of rules constitutes a ground for claiming the need for legislative change. Supported by Calabresi, D’Amato suggests that a (judicial) sunsetting of statutes comparable to the amendment of precedents performed by courts would increase legal certainty and ensure that legislation is updated. Hence, the need to take into account a change in circumstances can be regarded as a ground for admitting or even imposing a periodic revision of legislation: laws that are disconnected from the real world cannot provide for effective legal protection and, though they might be stable, they do not allow citizens to predict their rights and duties.
The fact that legislators revise rules, drawing benefits such as a tax exemption so as to ensure that new relevant circumstances are taken into account, is not contrary to the principle of legal certainty. This was notably ruled by the European Court of Justice (CJEU) in the Plantanol case:
In the context of Directive 2003/30 on the promotion of the use of biofuels or other renewable fuels for transport, it is not, in principle, contrary to the general principles of legal certainty and the protection of legitimate expectations for a Member State, with regard to a product composed of a blend of vegetable oil, fossil gas oil and specific additives, to withdraw, before the expiry date initially laid down in the national rules, the tax exemption scheme which applied to that product. In any event, such a withdrawal does not require the presence of exceptional circumstances. However, it is for the national court to consider, in the context of an overall assessment in the specific case, whether those principles have been observed by taking account of all relevant circumstances.
The CJEU affirmed that ‘the principle of legal certainty does not prohibit legislative amendment, imposing rather, that the legislator takes account of the particular situations of traders and provides, where appropriate, adaptations to the application of the new legal rules’. In this case, the German law under analysis (Law on Taxation of Energy, article 50(1)(1)) did not include a sunset clause. In any case, should legislators be able to foresee a rapid change of circumstances, the introduction of this provision (or alternatively a review clause) can give a sign to private actors that laws and regulations might need to be terminated or reviewed. If the CJEU admitted that amending a law to fit the circumstances does not violate the principle of legal certainty, then ‘announcing’ that this amendment might take place within two or three years will not either. Sunset clauses may even ensure that legislators will proceed to a reconsideration of all relevant circumstances.
Sunset clauses may be equally important when the effects of a new regulation are unknown, requiring their evaluation as more information as to the regulation’s effectiveness is gathered. Such uncertainty can be found in socially or ethically controversial laws or regulations. The evaluation criteria used here should be focused on the assessment of the effects and side-effects of the regulation in question. In addition, uncertainty has been suggested as a ground or a justification for the use of sunset clauses. This legislative strategy to guarantee the enactment of policies characterized by risk and uncertainty is, for example, visible in the German and US federal anti-terrorism laws mentioned earlier (see Chapter 2). The choice of sunset clauses was partially based on the uncertainty regarding the duration of the high terrorist threat.
In addition, the introduction of sunset clauses in controversial and uncertain laws, followed by an adequate evaluation, can increase their social acceptance because it reveals that regulators are willing to compromise and are open to review of regulations should these produce undesirable effects.
In conclusion, sunset clauses do not endanger the principle of legal certainty, instead this legislative instrument can be a valuable tool to enable legal changes; to provide temporary (legal) certainty; and to respond to situations characterized by acute uncertainty, risks, lack of information and decreasing effectiveness of rules.
-  This is the case of Ronald Dworkin, Taking Rights Seriously (HarvardUniversity Press, 1977) 286.
-  Anthony D’Amato, ‘Legal Uncertainty’ (1983) 71(1) California LawReview 1.
-  Ibid. 47.
-  Plantanol GmbH and Co. KG v. Hauptzollamt Darmstadt, Case C-201/08,Judgment of the Court (Third Chamber), 10 September 2009  ECRI-08343.
-  See Frans Jan Douglas and Tessa van den Berg (ZENC, study commissioned by ACTAL), Horizonwetgeving Dichterbij: onderzoek naar horizonwet-geving en regeldrukvermindering voor bedrijven (ZENC, 2010).
-  Funke, Burokratieabbau mit Hilfe zeitlich befristeter Gesetze, n. 53 above,