Taylor v Attorney-General for the Commonwealth

This matter came before the High Court of Australia concerning a dispute between Mr R. Merkel, QC, appearing for the plaintiff, and the Solicitor-General of the Commonwealth of Australia, Mr S.P. Donaghue, QC, appearing for the defendant. The proceedings involved a discussion regarding the drafting of question two of the case, which the Court identified as having three distinct bases for the plaintiff's contention that the Minister erred in refusing consent. These bases related to the Minister's alleged misunderstanding of customary international law, the binding effect of the Rome Statute on Australia's obligations, and the Executive's determination to implement the Rome Statute domestically.

The central legal issue before the Court was whether customary international law had changed as a result of the Rome Statute, specifically concerning immunity *ratione personae*. The plaintiff argued that the Rome Statute, by its widespread adoption, evidenced a change in customary international law, thereby altering existing immunities. The defendant contended that treaty law, particularly the Rome Statute, could not unilaterally alter customary international law in the manner suggested by the plaintiff, and that the plaintiff's argument was a misunderstanding of how customary international law evolves. The Court also considered the relevance of a further report from the International Law Commission, which appeared to conclude that no customary rule existed allowing for limitations on immunity *ratione personae* despite the Rome Statute.

The Court's reasoning focused on the need to clarify the precise state of international law for the purpose of the case. His Honour noted that the plaintiff's initial submissions on the first basis of question two were challenged by the International Law Commission's report. The Court indicated that if the plaintiff's contention regarding the change in customary international law was not supported by the evidence, the focus would shift to the second and third bases of question two, concerning the domestic legal obligations arising from the Rome Statute and the Executive's determination. The parties were directed to prepare full submissions on these matters, with specific dates set for the exchange of these documents to allow the Court to determine the appropriate course of action, including whether the case should proceed to a Full Court.