The plaintiff Sally Howell and the University had been parties to a number of Administrative Decisions Tribunal and Supreme Court cases ( some relevant posts here) concerning documents relating to the investigation of a complaint made against her as Deputy Principal of the Macquarie University Special Education Centre School.In those cases some documents had been found exempt, others were ordered to be disclosed . The defendant, Jenny O'Brien had advised the University about aspects of the complaint investigation conducted by a person engaged by the University for this purpose, and oversighted by the Ombudsman.
The main FOI related issue was whether in these proceedings the plaintiff could seek by subpoena documents held by the University previously found to be exempt by the Tribunal under the FOI Act on grounds of legal professional privilege. Both the Defendant and the University ( which appeared and made submissions but was not a party to the proceedings) asserted that the subpoena should be set aside, either because the Plaintiff was prevented by issue estoppel from challenging the claim of privilege, or because the subpoena constituted an abuse of the court’s process. Justice Patten discussed the relevant FOI history [25-49]), before considering estoppel:
"50 A long line of authority establishes the principle of issue estoppel defined thus by Dixon J in Blair v Curran“A judicial determination directly involving an issue of fact or of law disposes once for all of the issue, so that it cannot afterwards be raised between the same parties or their privies.”
51 In my opinion, the very issue debated before me upon the subpoena motion was decided adversely to Mrs Howell by the ADT the issue being that the subpoena documents were subject to legal professional privilege of the University.."
However, Justice Patten concluded that estoppel was not available as the University was not a party to the case before him and the Defendant was not a privy of the University, on this point citing  the following from the leading text on the subject:
“Res Judicata estoppels operate for, or against, not only the parties, but those who are privy to them in blood, title or interest. Privies includes any person who succeeds to the rights or liabilities of the party upon death or insolvency, or who is otherwise identified in estate or interest. It is essential that the party to be estopped by privity must have some kind of interest, legal or beneficial, in the previous litigation or its subject matter. Privity was described by the US Supreme Court as a mutual or successive relationship to the same right of property, although this cannot be exhaustive. Hence assignees will be bound as privies of the assignor."
However he found for the Defendant on the claim that the issue of a subpoena would involve re-litigation and constitute an abuse of process, citing the following from a decision of the NSW Court of Appeal :
"The guiding considerations are oppression and unfairness to the other party to the litigation and concern for the integrity of the system of administration of justice, and amongst the matters to which regard may be had are -
(a) the importance of the issue in and to the earlier proceedings, including whether it is an evidentiary issue or ultimate issue;
(b) the opportunity available and taken to fully litigate the issue;
(c) the terms and finality of the finding as to the issue;
(d) the identity between the relevant issues in the two proceedings;
(e) any plea of fresh evidence, including the nature and significance of the evidence and the reason why it was not part of the earlier proceedings; ...
(f) the extent of the oppression and unfairness to the other party if the issue was relitigated and the impact of the relitigation upon the principle of finality of judicial determination and public confidence in the administration of justice; and
(g) an overall balancing of justice to the alleged abuser against the matters supportive of abuse of process". “
Justice Patten rejected the Plaintiff's submission that new evidence had come to light since the ADT decision on the applicability of the FOI exemption that evidenced improper motive on the part of the Defendant, and that this brought into question the privilege claim.
The subpoena was set aside. Justice Patten then dismissed the defamation action on the basis that it was bound to fail because the alleged defamatory publication attracted absolute privilege by virtue of section 25H(2) of the Ombudsman Act. In the course of the decision he rejected a submission that the Defendant also enjoyed the benefit of clause 5 of Schedule 1 of the Macquarie University Act for limitation of liability for any person acting under the direction of the University or the Council in carrying out duties in good faith, because she as the University's employed solicitor, was not in any real sense acting under direction.