Outside the Text: Inside the use of Extrinsic Materials in Statutory Interpretation

AbstractWhen s 15AB of the Acts Interpretation Act 1901 (Cth) was enacted over 30 years ago, its purpose was to establish clear and particular rules about when extrinsic materials could be used in the interpretation of Commonwealth legislation. Accordingly, s 15AB stipulates three threshold tests, at least one of which must be satisfied before extrinsic materials can be considered as an aid to interpretation. However, developments in the common law since that enactment have largely overtaken the utility and effect of s 15AB (and its State equivalents). In particular, the development of the ‘contextual’ approach to statutory interpretation has meant that the common law now permits recourse to extrinsic materials, including parliamentary ones, without the need to pass any gateway test. Consequently, the important emerging issue is, not when such materials can be considered, but how they may be used. This article, using recent High Court cases, examines some of the key threads that have emerged about the ‘appropriate use’ of parliamentary materials, particularly with respect to identifying the purpose of the statute and as against the weight of the statutory text.