A PREVIOUS COLUMN discussed the role and purpose of an amicus curiae in common law jurisdictions, civil law jurisdictions and areas of international law. It also examined the potential for the role of an amicus curiae to develop in mainland China (see Amicus curiae). This column discusses the role and purpose of an intervener in common law jurisdictions and examines a recent example in New Zealand.

Difference between an amicus curiae and an intervener in common law jurisdictions. As noted in the previous column, an amicus curiae is not a party to the dispute. By comparison, an intervener is a party to the proceedings – at least in a technical sense – and is subject to all the benefits and burdens of a party. For example, an intervener can appeal, tender evidence and participate fully in the proceedings. At the same time, an intervener will be bound by the court’s decision (to the extent that it is applicable to the intervener) and may also be subject to an adverse costs order requiring the intervener to pay all or some of the costs of the other parties.

In some cases, it is difficult to draw a clear distinction between the role of an amicus curiae and the role of an intervener. Similar to an amicus curiae, an intervener may wish to provide specialist knowledge or expertise to the court, to inform the court and to assist the court in making a decision.

It is relevant to note that in many common law jurisdictions, there is very little, if any, written law or legislation that governs the role of amicus curiae or intervener. Instead, the power of courts to recognise these roles is based on their inherent jurisdiction to request assistance in relation to their deliberations and decision-making function.

Further, special circumstances need to exist before a court will exercise its discretion to permit an intervener to participate in the proceedings. The criteria for the exercise of discretion vary from jurisdiction to jurisdiction. In the UK, for example, it has been said that courts have permitted an intervener in circumstances where the intervener intends to raise issues of public interest that have not been addressed by the parties, and where the participation by the intervener would serve the interests of justice.

In Australia, the courts have made reference to the need for interveners to demonstrate a “special interest” in the subject of the proceedings, and have indicated that this requirement is satisfied where it is shown that the special interest is more than a “mere intellectual or emotional concern”.

The rules of civil procedure in some jurisdictions set out a procedure by which a person may apply to intervene. For example, the rules in the state of Victoria in Australia make provision for a person to intervene in an appeal proceeding where the person satisfies the Court of Appeal that:

  • The applicant’s contribution as an intervener will be useful and different from the contribution of the parties;
  • The intervention would not unreasonably interfere with the conduct of the application or appeal; and
  • Any other matter that the Court of Appeal considers relevant.

In recent times, “public interest” interveners have come to be recognised as a subset of interveners generally. The term “public interest” interveners refer to persons who wish to participate in litigation for the public interest. Such interveners make submissions in relation to how a case might affect the public interest and help the court to understand the implications from this perspective. This is in addition to the traditional practice of allowing representatives of the state, such as the attorney­ general, to intervene in constitutional and other cases to protect the public interest. A recent example of a public interest intervener is discussed below.

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This column draws on an article by Zhang Yang and Andrew Godwin titled Administrative Enforcement of Insider Trading in China: An Empirical Study (2022), in Company and Securities Law Journal.

Andrew Godwin

Andrew Godwin previously practised as a foreign lawyer in Shanghai (1996-2006) before returning to his alma mater, Melbourne Law School in Australia, to teach and research law (2006-2021). Andrew is currently Principal Fellow (Honorary) at the Asian Law Centre, Melbourne Law School, and a consultant to various organisations, including Linklaters, the Australian Law Reform Commission and the World Bank.