Abstract
The interface between state legal systems and customary law is the site of a number of complex problems. A particular difficulty lies in accommodating customary law in formal common law court processes, which are typically driven by the adversarial system. An important but much neglected issue within this area is how best to approach the proof of customary law in courts. A threshold question that arises is whether it should be treated as law or fact. Few countries give any legislative guidance on this issue, nor has it been the subject of extensive consideration by the courts themselves. This article examines the issue of proof of customary law and a number of associated questions, focusing on the common law courts in Australia. Comparison is drawn with the position in neighbouring South Pacific Island States, which are also grappling with this issue. The article commences with a discussion of proof of customary law within the broader context of legal pluralism. It then moves on to a survey of the legislation that impacts on proof of customary law in civil and criminal proceedings in Australian courts. Some illustrative case law is then explored. The article assesses the adequacy of the current regime and considers some of the options for reform.