Interpretive Presumptions Assessed against Legislators’ Understanding

Abstract

Courts have long used a range of presumptions in interpreting statutes, as a means of giving some effect to fundamental rights and principles and to international law obligations: they have presumed that, absent indications to the contrary, Parliament must have intended to legislate consistently with these. These interpretive presumptions include the presumption of consistency with fundamental common law rights (the so-called ‘principle of legality’); the older and simpler device of ‘rules of strict construction’ of legislation affecting certain fundamental rights and principles; the presumption of consistency with the Treaty of Waitangi that may be recognized in NZ; and the express interpretive instructions to prefer rights-consistent meanings that appear in statutory bills of rights. The strength of use of such interpretive presumptions has fluctuated over time and has varied according to the subject matter and context. Recent decades have seen stronger uses at least in certain areas. Particularly ‘adventurous’ use has been made in the UK of the express instruction in s 3 of the Human Rights Act 1998 (UK) to interpret legislation consistently with the rights in the European Convention of Human Rights. Similarly assertive use has been made in NZ of the common law presumption of consistency with unincorporated international treaties. Australia has seen some fairly strong uses of the principle of legality. There has been much spirited debate on whether such strong uses can be justified. In this essay, I ask a prior question: how do we decide what amounts to a strong use that calls for special justification? I examine this question from the perspective of one who considers that democratic principles normally call for interpreters of statutes to respect the intention of the enacting Parliament (or better: legislators’ likely understanding). An explanation and defence of this position is a topic for another paper; here I provide only a very brief summary. My contribution here is to work through the implications that follow for assessing the strength of uses of interpretive presumptions if we take respect for legislators’ likely understanding as our starting point. First, I propose a test for distinguishing between assertive uses that call for special justification and weak or moderate uses that do not, and explore the application of that test. Secondly, I identify and compare the different tests established in the cases for the three main presumptions, and assess each of them against my criterion of respect for legislators’ likely understanding. My examination extends to the UK, Australia, and NZ — three common law jurisdictions without constitutional bills of rights.