The proceeding concerned an application by the Australian Workers’ Union (AWU) seeking to quash the decision of the Registered Organisations Commissioner to investigate whether the AWU had breached relevant provisions of the Workplace Relations Act 1996 (Cth). As part of the proceeding, the AWU issued a subpoena to the Secretary of the Department of Jobs and Small Business (Department). In complying with the subpoena, the Secretary, the Department and the Minister, Ms Kelly O’Dwyer MP, objected to production of six of the documents on the grounds they were subject to legal professional privilege. The AWU submitted that the privilege had been waived by the previous Minister, Senator Michaelia Cash, or her chief of staff. His Honour Justice Wheelahan first assessed who held the privilege in these circumstances. His Honour dismissed the initial argument of both parties and held that the Crown was the entity who held the privilege, as the advice sought from Departmental lawyers was done in the exercise of Senator Cash’s executive powers. As to the second issue of waiver, Justice Wheelahan rejected the AWU’s submission that Senator Cash or her former chief of staff had impliedly waived privilege in giving evidence in the proceeding, as Senator Cash was no longer the relevant Minister, and did not appear to have the authority to waive the privilege. His Honour thus upheld the claim for privilege over the six documents.