The test for intervention in rule 9.12 of the Federal Court Rules 2011 (Cth)
9 Rule 9.12 of the Federal Court Rules is concerned with applications for intervention. It provides as follows:
Interveners
(1) A person may apply to the Court for leave to intervene in a proceeding with such rights, privileges and liabilities (including liabilities for costs) as may be determined by the Court.
(2) The Court may have regard to:
(a) whether the intervener's contribution will be useful and different from the contribution of the parties to the proceeding; and
(b) whether the intervention might unreasonably interfere with the ability of the parties to conduct the proceeding as the parties wish; and
(c) any other matter that the Court considers relevant.
(3) When giving leave, the Court may specify the form of assistance to be given by the intervener and the manner of participation of the intervener, including:
(a) the matters that the intervener may raise; and
(b) whether the intervener's submissions are to be oral, in writing, or both.
10 Rule 9.12 is not expressed in the older language of requiring a person to be a "necessary or proper party" before that person would be joined to the action. That older rule was the origin of the "direct interest" test discussed below.
11 In Roadshow Films Pty Ltd v iiNet Limited [2011] HCA 54; (2011) 248 CLR 37, 38 [2] - [4], a joint judgment of the High Court reiterated remarks of Brennan CJ in Levy v Victoria [1997] HCA 31; (1997) 189 CLR 579, 600-605, and explained as follows:
A non-party whose interests would be directly affected by a decision in the proceeding, that is one who would be bound by the decision, is entitled to intervene to protect the interest likely to be affected. A non-party whose legal interest, for example, in other pending litigation is likely to be affected substantially by the outcome of the proceedings in this Court will satisfy a precondition for leave to intervene. Intervention will not ordinarily be supported by an indirect or contingent affection of legal interests following from the extra-curial operation of the principles enunciated in the decision of the Court or their effect upon future litigation.
Where a person having the necessary legal interest can show that the parties to the particular proceedings may not present fully the submissions on a particular issue, being submissions which the Court should have to assist it to reach a correct determination, the Court may exercise its jurisdiction by granting leave to intervene, albeit subject to such limitations and conditions as to costs as between all parties as it sees fit to impose.
The grant of leave for a person to be heard as an amicus curiae is not dependent upon the same conditions in relation to legal interest as the grant of leave to intervene. The Court will need to be satisfied, however, that it will be significantly assisted by the submissions of the amicus and that any costs to the parties or any delay consequent on agreeing to hear the amicus is not disproportionate to the expected assistance.
12 This passage from the High Court has also been applied in the context of the Federal Court Rules: Congoo v State of Queensland [2013] FCA 1113 [20] (Logan J); Hua Wang Bank v Commissioner of Taxation [2013] FCAFC 28 [51] (Logan, Jagot and Robertson JJ).
13 In Roadshow Films the High Court can be understood to be saying that the requirement of "direct interest" will establish an entitlement to intervene, but if there is no direct interest then leave to intervene may be granted if the non-party's legal interest is "likely to be affected substantially by the outcome of the proceedings". However, an indirect interest, following from the extra-curial operation of a decision or its effect on future litigation is not sufficient.
14 Consistent with this is the discussion of Brennan CJ in the decision followed by the High Court in Roadshow Films. In Levy v Victoria [1997] HCA 31; (1997) 189 CLR 579, 603, Brennan CJ explained the reasons why "an indirect affection of legal interests enlivens no absolute right to intervene" before explaining the circumstances in which "the necessary legal interest" might permit a discretionary grant of leave to intervene.
15 I do not accept Mineralogy's submission that leave to intervene will only be granted where a party's interests are directly affected. Nevertheless, it is clear that the less direct the interest of the non-party, the more unlikely it will be that intervention will be allowed. See also Comcare v Martinez [2013] FCA 160 [14] (Robertson J).