Evolution of the common law principle of "issue waiver"

The term "issue waiver" is an established part of the Australian legal lexicon. And yet, considerable confusion remains over precisely what issue waiver is, and when it will arise to defeat a claim of legal professional privilege. This article seeks to redress this confusion by examining the development of the common law principle of issue waiver in Australia. The article charts the evolution of issue waiver in Australian case law, from its origins as a distinct ground of waiver to its eventual subsumption under the general principle of implied waiver. In so doing,it pays particular attention to the impact this evolutionary process has had on the scope of the issue waiver exception to legal professional privilege.