Invalidity and Retrospectivity under the Irish and Canadian Constitutions

Abstract

The question of the temporal effect of a finding that a statute is unconstitutional has arisen in a number of common law jurisdictions. In any legal system that allows its superior courts to strike down legislation, certain practical problems will inevitably emerge. This article explains this aspect of Irish constitutional interpretation and compares the manner in which these difficulties have been addressed under the Canadian and Irish constitutions. It notes that the Supreme Court of Canada was required to address these practical problems directly at an early stage and thus developed a more doctrinally coherent approach to findings of constitutional invalidity than the Irish Supreme Court. The article goes on to analyze a recent decision of the Irish Supreme Court that has highlighted the difficulties with the approach adopted in that legal system and concludes with some reflections on the relative merits of the Canadian approach to findings of invalidity.