The Encyclopaedic Australian Legal Dictionary (LexisNexis AU) can help.
An explanatory memorandum is an executive document issued at the same time as a bill. It's purpose is to explain the aims and operation of the statute. In statutory interpretation, if the meaning of a provision in an Act is ambiguous or obscure, reference may be made to explanatory memoranda in order to ascertain the meaning of the provision.
A Law Reform Commission is an organisation with a focus on the systematic development, review and reform of the law in a particular jurisdiction. Each Australian state and territory and the Commonwealth have associated law reform agencies. As a result of Commission inquiries and projects, publications are produced including background papers, issues papers, consultation papers and final reports.
When a bill is debated in parliament, it is sometimes necessary to refer the bill to a committee, which specialises in the subject area of the bill, for an advisory report.
A speech given by the relevant Minister in parliament outlining the policy underlying a proposed law (a Bill) during the second reading. Second reading speeches are included in the published parliamentary debates known as Hansard. They are particularly useful in determining the historical intent of new and amending legislation. As an aid to statutory interpretation, second reading speeches may be used to discern the underlying purpose or object of a statute.