Chapter 15 - Representation and other participants

Other participants

The courts do allow the participation of different types of non-parties in a case. These can be important in the case of a self-represented litigant. Equally, they can be completely independent of either party, but of great assistance to the court. This section looks at the following types of participants to see whether further legislative intervention is needed that may involve new courts legislation:

  • McKenzie friends;
  • amicus curiae;
  • technical advisors; and
  • interveners.

McKenzie friends

Any unrepresented party to civil or criminal litigation is entitled to have a support person to provide assistance in court. The support person may attend as a friend of the party, may take notes, may quietly make suggestions and may give advice.457  These support people are known as “McKenzie friends” after the United Kingdom case that confirmed their legitimacy.458 McKenzie friends are permitted in almost all common law courts.459

A McKenzie friend does not have the right to take part in the proceedings as an advocate. However, the court has the discretion to allow the friend to play a greater role, such as speaking for the party if they think this is appropriate. This discretion must be exercised in the proper manner and in the interests of justice. The opposing party is equally entitled to a fair trial. If the court considers that a particular McKenzie friend will obstruct the efficient administration of justice then the court can decline to allow that person to act as a McKenzie friend or remove someone who is already acting as a McKenzie friend.460

In the United Kingdom, there was confusion among litigants and their friends and relatives about the role that a non-lawyer support person could play in court. Despite expectations that these support people could turn up to court and address the court on behalf of a litigant, cases such as Izzo v Philip Ross & Co461 made it clear that permission for a McKenzie friend to address the court was an indulgence and courts should consider matters on a case-by-case basis.462 There were, however, some inconsistencies in the rules applied to McKenzie friends.463 This led to requests for further guidance on representation in the Civil Procedure Rules and practice notes. The Master of the Rolls as the Head of Civil Justice has issued a guidance note on McKenzie friends for the Civil and Family courts.464 This outlines what a McKenzie friend can and cannot do. It states that a self-represented litigant has the right to use a McKenzie friend and the litigant should apply requesting the assistance at the earliest possible stage and provide details of the proposed McKenzie friend. It makes it clear that the court should provide reasons for a decision to refuse to allow a litigant to use a McKenzie friend. The Civil Justice Council has also recently proposed a draft code of conduct for McKenzie friends.465

There have been cases involving “professional” McKenzie friends. These are people from support groups or non-governmental organisations who have experience helping litigants with court proceedings.466 An example in the United Kingdom was Dr Pelling, a campaigner for fathers’ rights who frequently acted as a McKenzie friend. On occasion he was refused leave to act as a McKenzie friend on the basis that his campaigning agenda and adversarial approach were not considered appropriate, and his experience may have led him to conduct the case himself rather than remain in the role of an assistant.467

A McKenzie friend could be a lawyer who is not “on the record”, as was the case in McKenzie v McKenzie.468 However, a lawyer, whether funded privately or by legal aid cannot be obliged to accept the role of McKenzie friend if he or she is unwilling to do so. In R v Hill, the Court of Appeal discussed the fact that there does not seem to be any authority for allowing lawyers to act as McKenzie friends.469 The Court noted that this raises issues about legal professional privilege, the duties and liability of a lawyer to the accused, and the lawyer’s duty to the court.470

There has been some speculation that the global financial crisis and the straitened circumstances of more litigants may lead to an increase in the reliance upon McKenzie friends rather than lawyers.471 Greater use of McKenzie friends could create a greater need for guidelines or regulation of the role of McKenzie friends in the New Zealand courts.


Are there any problems with the use of McKenzie friends?


Should McKenzie friends be permitted in court?


If so, should there be legislation, regulations or guidelines outlining the role of McKenzie friends in the New Zealand courts?


Should a person be able to have a lawyer as their McKenzie friend?

Amicus curiae

An amicus curiae, or friend of the court, is not a party to an action, but a person appointed by the court to assist it, either by providing information and submissions about a particular area of the law or, where one of the parties is unrepresented, by advancing legal arguments on that party’s behalf.472 The former role involves giving assistance to the court in a neutral and comprehensive way, ensuring all aspects of a dispute are teased out and addressed. The latter may involve partisan advocacy, including confrontation with opposing counsel.473

The appointment of an amicus, and the extent to which he or she may file documents and present arguments, are at the discretion of the court. The appointment of an amicus does not require the consent of the parties.474


What is the role of an amicus?

In the United Kingdom, a memorandum issued to judges in 2001 makes it clear that the role of the amicus in that country is expressly rooted in assistance to the court.475 The court may seek the assistance of an amicus (renamed an “advocate to the court”) when there is a danger of an important and difficult point of law being decided without the court hearing relevant argument. The function of the advocate to the court is to give the court assistance on the relevant law and its application to the facts of the case. It is not his or her function to represent anyone.

In New Zealand, the term amicus curiae is used to cover a wider range of circumstances where counsel are appointed to assist the court. They have been appointed:

(a)to present legal arguments for a party who does not or cannot appear;476

(b)for a class of persons that might be affected by a judgment;477

(c)where a party to a proceeding is not represented by counsel in certain circumstances, such as where he or she is unfit to represent him or herself,478 or is unable to obtain representation;479

(d)where the case raises complex issues such as matters of human rights or international law.480

Despite the range of roles an amicus may take on, the core of the role remains constant: an amicus does not act on instructions from a party to the proceedings or a client. The amicus selects independently arguments which he or she thinks are appropriate to put before the court, or discharges requests from the court for analysis of a particular matter.481

Appointment of an amicus curiae

The power to appoint counsel to assist the court is not explicitly provided for by statute, but is grounded in the inherent jurisdiction of the High Court. There are some express powers to appoint counsel. For example, rule 4.27 of the High Court Rules and rule 3.33.8 of the District Courts Rules provide that the court may make certain directions in relation to representation of specified classes of person or the public interest, on application by a party or an intending party, or on its own initiative. Among the available directions, the court may appoint counsel to represent minors, unborn persons, absentees or unrepresented persons; or direct that the Attorney-General or the Solicitor-General be served; or that any chief executive of a Government department or other officer may represent the public interest.

In a civil proceeding, section 61A of the Judicature Act 1908 provides that a single judge of the Court of Appeal may make incidental orders or directions in relation to a proceeding, provided the order or direction does not “determine the appeal or dispose of any question or issue that is before the court in the appeal or proceeding”.

Rules 5 and 7 of the Court of Appeal Civil Rules provide that a single judge may “give any directions that seem necessary for the just and expeditious resolution of any matter that arises in the proceeding”. Rule 5 of the Supreme Court Rules 2004 provides a similar power in relation to “any matter that arises in a case”, and rule 7 provides the power may be exercised by a single permanent judge.

In relation to criminal proceedings, section 333(4) of the Criminal Procedure Act 2011 is drafted in similar terms to secion 61A of the Judicature Act 1908 (although section 333(4) is not yet in force).

When should an amicus be appointed?

In Levy v Victoria, Brennan CJ said that the footing on which an amicus curiae is heard is that the person is willing to offer the court a submission on law or relevant fact that will significantly assist the court.482 He added a proviso – any cost to the parties or any delay consequent on agreeing to hear the amicus must not be disproportionate to the assistance that is expected.

In our view, care should be taken not to allow the role of counsel assisting the court to become a surrogate or parallel legal aid system. Where a party chooses to be self-represented, appointment of a friend of the court may be inappropriate. Similarly, where legal aid has been declined and the affected party seeks the appointment of counsel to assist the court, care must be taken not to undermine the legal aid decision.

When counsel to assist is appointed, his or her duty is to provide whatever assistance the court requires. He or she is not a party to the appeal and has no entitlement to be heard. Both the appointment and the extent to which the appointed counsel may file documents and present legal argument is an exercise of the court’s discretion.483  It is very important that the extent of counsel’s brief is communicated clearly when he or she is appointed.

Counsel assisting the court is expected to assist the court in a neutral and comprehensive way. His or her assistance will, however, often require him or her to advance a particular stance or viewpoint. The Court of Appeal has held that in the context of contempt proceedings there is nothing wrong with counsel assisting the court adopting a partisan role.484

Where an amicus is appointed to represent the interests of an otherwise unrepresented person or group, he or she will almost inevitably present partisan argument.485 This can create some conceptual difficulties. In The Beneficial Owners of Whangaruru Whakaturia No 4 v Warin & Ors, the appellants sought to appeal against a decision of the High Court holding that the first respondents had an indefeasible title in respect of certain land. The appellants, the beneficial owners of the land, were never parties to the proceeding, but counsel was appointed by the High Court as amicus curiae. The Court of Appeal noted that although in formal terms, counsel was appointed as amicus, the manner in which he approached his brief blurred that role, and in the end he advanced the interests of the appellants as if they were parties to the proceeding.

The Court of Appeal held that the beneficial owners of the land did not have standing to appeal. It noted that the case demonstrated how, if an amicus is permitted to participate in a proceeding essentially as a party, confusion may result as to rights and obligations in subsequent stages of the proceeding:486

The issue for us is the right of appeal, but the potential problems where successful parties want to seek costs against an amicus whose participation in the proceeding necessitate substantial additional work for the parties, are very real. Although there is provision for the payment of costs from public funds under the Judicature Act, that could be problematic where the participation of an amicus strays into the realm of truly partisan advocacy rather than impartial presentation of information to the court.

The Court suggested that if the genesis of the amicus’s inclusion in a proceeding is viewed as emanating from the court, rather than from an instructing party, then conceptual problems such as whether there is a right to appeal disappear. Once judgment is issued, the court’s need for the amicus is exhausted, whether or not the represented group’s interest has prevailed.487

One issue that arises is that the distinction between an amicus curiae and an intervener can become blurred. In cases where the issues that the non-party will address require substantially partial legal argument, it may be more appropriate that the non-party seeks leave to appear as an intervener (discussed below), rather than the court appointing an amicus. The High Court discussed the distinction between an amicus curiae and an intervener in Auckland Area Health Board v Attorney-General.488 That case concerned an application by doctors from the intensive care unit of Auckland Hospital for a declaration clarifying whether in law they would be guilty of culpable homicide if they withdrew the ventilatory-support system maintaining the breathing and heartbeat of a patient with advanced Guillain-Barre syndrome.

The Attorney-General was originally named as a defendant in the proceeding, but the proceeding was then reconstituted as an originating application. The Attorney-General was granted a right of appearance. He originally wished to be heard as amicus curiae, to bring relevant factual and legal considerations to the attention of the court. However, the High Court suggested that this status would not be appropriate, as the Attorney-General had responsibilities in the matter in his own right – the relief sought, if granted, would impinge on the prosecutorial discretion and prerogative powers of the Crown.489 Accordingly the Attorney-General sought, and was granted, leave to be heard as intervener.

Where the court requires the assistance of counsel because one of the parties is no longer legally represented, it may be the most efficient practice to appoint that party’s former counsel.490  In Duncan v Medical Practitioners Disciplinary Committee, the Court of Appeal was faced with a respondent who indicated that he did not intend to take part in the appeal.491  Because the case raised issues of public importance, the Court decided to appoint counsel who had appeared for the respondent in the High Court to assist the court. This is a practice which has also been endorsed in relation to criminal cases.492 Where counsel was appointed to assist the lower court, that counsel will generally be retained, if needed, for the appeal.493

Legislative reform

A question for consideration is whether the power to appoint an amicus curiae should be codified in legislation. Such a provision could provide clarity about when an amicus curiae can participate in a case and what role they may have.


Should there be a specific statutory provision in the new Courts Bill enabling the appointment of amicus curiae?


If so, on what grounds/in what circumstances should an amicus be appointed?

Technical advisors

Section 99B(1) of the Judicature Act 1908 gives the Court of Appeal and the Supreme Court the power to appoint a technical adviser to assist it in an appeal where questions arise from evidence relating to scientific, technical, or economic matters, or from other expert evidence. The technical adviser’s advice may be given such weight as the court thinks fit.494

A technical advisor may be appointed at the impetus of the court itself or following application of one of the parties.495 The court may remove an advisor for the reasons of disability affecting performance, neglect of duty, bankruptcy or misconduct, and an advisor may resign.496 The court determines the rate of remuneration for the advisor.497

Sections 99B to 99D, which provide for the role of a technical advisor, were inserted in 1999,498 and amended in 2003 to take into account the establishment of the Supreme Court.499

We are not aware of any cases in which a court has used its power under section 99B to appoint a technical adviser, and so as Williams J noted in 2000, the courts’ approach to the appointment of technical advisers is uncharted territory:500

In particular, this Court is unaware whether the Court of Appeal is likely to seek the adviser’s assistance by having [the] adviser sit with it during a hearing or whether such assistance will only be given out of Court. Both possibilities seem to be open on the terms of s 99B.


Why have the provisions of the Judicature Act 1908 allowing the appointment of technical advisors not been used?


Is there a need for guidelines for technical advisers, including matters such as who can be an adviser, and what type of evidence they can give?


Intervention is a procedure that allows non-parties to become involved in litigation. These non-parties are known as interveners. Interveners remain as non-parties to the litigation in that they do not have a direct stake in the outcome of the case, but they may participate in it by making written or oral submissions to the court. There is no clear legislative basis for intervention in New Zealand.501 The High Court Rules, Court of Appeal Rules and Supreme Court Rules are silent on third party interventions. Nonetheless, there appears to be a healthy practice of third party interventions. Interveners have appeared in the New Zealand Supreme Court at least 16 times since 2004.502

The authority of the court to allow intervention comes from its inherent jurisdiction. There is nothing in the rules of court to prevent the court exercising its inherent jurisdiction to join an interested party in an appropriate case.503 The Human Rights Commission has as one of its functions the role of applying to court to act as an intervener in proceedings if doing so will facilitate it being an advocate for human rights.504

Interventions by third parties can be in the public interest or for the intervener’s own private interest, depending on the aim of the intervener. Interveners in the private interest are less common because someone whose private interests are directly affected by a case can be named as an interested party by the claimant or defendant, joined as a party by the court, or can apply to join the case as a party themselves.505 However, sometimes there are interveners in the private interest.506 The Attorney-General regularly intervenes in cases for the Government. Intervention is most common in judicial review cases,507 as frequently:508

…the challenge to the exercise of the statutory power or decision of a public body will have consequential effects upon others who obtained beneficial entitlements or expectations following upon the exercise of such power.

Unlike general intervention by non-parties, there is a long history of authority for public interest intervention by the Attorney-General in New Zealand.509 The main relevant authorities for the role of interveners are those from the High Court and the Court of Appeal.

Intervention can provide the court with an enhanced perspective on the questions at issue in the proceedings, promote better and more informed decision-making and increase public acceptance of court decisions. Intervention by individuals, public interest groups and others can play an important part in presenting a court with the perspectives it needs in order to make fully informed decisions. It may also allow broader participation in litigation, particularly from non-traditional interests who may otherwise find it difficult to gain access to the judicial system.

But intervention can also raise issues of potential prejudice and unfairness to the original parties to the proceeding. As Lord Woolf has noted:510

The practice of allowing third persons to intervene in proceedings brought by and against other persons which do not directly involve the person seeking to intervene has become more common in recent years but it is still a relatively rare event. The intervention is always subject to the control of the court and whether the third person is allowed by the court to intervene is usually dependent upon the court’s judgment as to whether the interests of justice will be promoted by allowing the intervention. Frequently the answer will depend upon whether the intervention will assist the court itself to perform the role upon which it is engaged. The court has always to balance the benefits which are to be derived from the intervention as against the inconvenience, delay and expense which an intervention by a third person can cause to the existing parties.

Overseas experiences have indicated that a well-regulated system of public interest intervention can both assist the courts and increase public confidence in the judiciary.511

It has been argued that the lack of regulation regarding intervention does not provide sufficient certainty as to when an application for intervention will be accepted or the type of conditions that will be attached to each intervener status.512


When is intervention allowed?

Traditionally it has been difficult to convince the court that intervention is justified. Courts have been reluctant to depart from the traditional privity of litigation. However, it appears that interventions are becoming more common. Public interest intervention is a relatively recent development that can be seen as following on from the increasing acceptance of the law-making role of the courts that has developed internationally in recent decades.513 In other comparable jurisdictions intervention has increasingly been allowed where the applicant has a significant interest in the litigation and the participation of an intervener will not unduly delay or prejudice the determination of the rights of the original parties. With the exception of Canada, Commonwealth jurisdictions generally have a relatively undeveloped system and jurisprudence for intervention.514

In New Zealand, a new approach is emerging in some cases, particularly public law matters such as New Zealand Bill of Rights Act 1990 cases, which have the potential to affect many people far beyond the immediate dispute. A case may be appropriate for an intervention if it raises an issue of public importance, and there is a risk that this public interest may not be sufficiently addressed by the submissions of the parties alone. In Drew v Attorney-General, McGrath J held that an intervention should be allowed “where the assistance likely to be offered outweighs any potential detriments to the various interests”.515 The primary consideration appears to be whether the assistance from an intervener’s submissions goes beyond the assistance that counsel for the parties can provide.516


Interveners are sometimes given leave to make oral presentations, and other times they are restricted to written submissions. In the United Kingdom, the general rule is that the proposed intervener must approach the parties for their consent to the intervention. The courts generally grant leave to intervene despite at least one party having refused consent, but the requirement allows the parties to express their views to the court. This is particularly important in relation to whether an intervener is granted leave to make oral submissions at the hearing: a party may consent to an intervention by way of written submissions, but not to oral submissions.517

Often intervention is granted on terms that restrict the intervener’s role. The court must consider whether the intervener should be bound to take the record as it is and not adduce further evidence; whether the intervener should be prevented from being able to seek costs even where costs may be able to be awarded against them; and requirements as to the promptitude of filing any necessary papers.

Interveners can be required to meet the additional costs of other parties occasioned by their intervention.518 Whether they can be liable for costs additional to this is not clear.

In practice, it is often not until the appeal stage that a case picks up some momentum, and this is when some interveners try to get involved. These interveners can then sometimes seek leave to introduce new evidence on the appeal. However, in principle there is no prima facie right to add to the record upon being granted status as an intervener. It can be problematic to have a large amount of additional material introduced at this stage and to provide fair notice to parties in an appellate proceeding. It may be that there should be rules regarding the introduction of new evidence and the relevance of interveners’ submissions.

Intervention in other countries

In the United Kingdom, the practice of third party interventions in the higher courts has been described as having grown steadily from about 1995, a trend that has been attributed in part to the passage of the Human Rights Act 1998 (UK):519

Even before the Act was passed, UK courts had already begun to pay greater attention to the provisions of the European Convention on Human Rights. And it is likely that UK courts were mindful of the much more generous provision for third party interventions before the European Court of Human Rights.

Unlike New Zealand, the United Kingdom’s legislation makes explicit provision for interveners. The rules of the Appellate Committee of the House of Lords,520 the United Kingdom Supreme Court,521 the Privy Council522 and the European Court of Human Rights all make explicit provision for third party interventions. The procedure rules for the Supreme Court make provision for applications to the Court for permission to intervene in an appeal by:523

(a) any official body or non-governmental organization seeking to make submissions in the public interest,

(b) any person with an interest in proceedings by way of judicial review,

(c) any person who was an intervener in the court below or whose submissions were taken into account. 

There is a prescribed application form, and interventions may be allowed by written submissions only or by way of both oral and written submissions.524

While the Civil Procedure Rules that govern the United Kingdom High Court do not refer to interventions directly, the Practice Direction to Part 54 of the Rules refers to “applications to intervene”,525 and there is a procedure in the rules governing judicial review proceedings that allows interventions in practice. However, there is no formal provision for interventions in the Court of Appeal, which is where many interventions occur.526 There is no consistency of practice and there are at least two methods by which a party can apply to intervene in the Court of Appeal: a formal application, or a letter to the Civil Appeals Office requesting leave to intervene.

As in New Zealand, there is no legislation setting out when interveners should be allowed. Third parties have been allowed to intervene because of their knowledge, concern and experience.527

The Rules of the Supreme Court of Canada have allowed significant participation of interveners since 1987,528 and intervention “has become the norm rather than the exception in cases before the Supreme Court of Canada”.529 A group or individual has a right to intervene before the Supreme Court where they were granted leave to intervene in the court below and the Attorney-General of a province, territory or the federal government may intervene as of right if there is a constitutional question before the Court.530 In all other cases, leave of the Court must be given to intervene.531 Applications must identify the applicant, and their interest in the proceeding, “including any prejudice that the person interested in the proceeding would suffer if the intervention were denied”.532 An important provision requires an intervener not to duplicate the submissions of the parties but instead to:533

… set out the submissions to be advanced by the person interested in the proceeding, their relevance to the proceeding and the reasons for believing that the submissions will be useful to the Court and different from those of the other parties …

Australia has taken a somewhat more restrictive approach, and there has been relatively little jurisprudence on interventions. The High Court of Australia’s approach has been largely ad hoc. It was not until the mid-1990s that the Court began to expand the grounds for intervention beyond the test of strict legal interest.534 In the case of Levy v Victoria the Court allowed the intervention of a number of interveners, including state attorneys-general and media organisations, on a question of whether state duck hunting regulations raised free speech implications.535 Chief Justice Brennan noted that an intervener must ordinarily show an interest that would be directly affected by a decision, but that legal interests may be affected in indirect ways, such as the operation of a precedent.

Legislation for interveners

The rising scope for intervention could be seen as increasing the need to spell out in legislation such matters as when interveners should be allowed, and what their rights are. The Commission’s view is that any legislative provisions should enable the court to have sufficient discretion to tailor the extent of the role of the intervener to the particular proceedings, allowing the court to maximise efficiency and balance the concerns of both the parties and the intervener.

While it may be useful to have a provision stating the court’s power to grant a third party leave to act as an intervener, it is likely that details regarding the process for intervention and role of an intervener are more suited to being set out in rules than in the new consolidated courts statute.


The matters that could be clarified in rules include:

  • the costs that an intervener can be liable for;
  • the process for making an application to intervene, and what material the prospective intervener must provide to the court;
  • the time for filing an application;
  • criteria for determining whether leave to appear will be granted;
  • when an intervener may give written submissions and oral submissions;
  • any restrictions on the parameters of matters that interveners can discuss; and
  • whether new evidence can be introduced by an intervener at an appeal stage.


To what extent should legislation set out the law relating to interveners? What matters should be addressed in rules?


What rights should be accorded to interveners? Are there any rights of parties which interveners should not have?

Mihaka v Police [1981] 1 NZLR 54, citing Collier v Hicks (1891) 2 B & Ad 663, 109 ER 1290 and McKenzie v McKenzie [1970] 3 All ER 1034. Applied in Muir v Police (1986) 2 CRNZ 12.

McKenzie v McKenzie [1970] 3 All ER 1034. This was a divorce case in which the husband had had legal aid withdrawn. An Australian barrister unqualified to appear in court in the United Kingdom offered assistance. While the trial judge declined to allow this support person’s assistance, on appeal it was held that Mr McKenzie was entitled to the assistance of such a person.

C Cameron and E Kelly “Litigants in person: Part I” (2002) 32 HKLJ 313 at 319.

A Northover and N Fisher “Keeping it in the family: Will the credit crunch tempt more litigants to adopt a McKenzie friend?” (2008) 158 New Law Journal 1739 at 1739.

Izzo v Philip Ross & Co [2001] All ER (D) 464.

Judge S Stevenson “’I am his litigation friend’” (2001) 151 New Law Journal 1726.

B Hansen “Common Law McKenzie Friend” (July 2011) Bond University < > at 10.

The latest version is Lord Neuberger of Abbotsbury, Master of the Rolls, and Sir Nicholas Wall, President of the Family Division “Practice Guidance: McKenzie Friends (Civil and Family Courts)” (12 July 2010).

Civil Justice Council Access to Justice for Litigants in Person (or self-represented litigants) (November 2011) at App 5.

A Northover and N Fisher “Keeping it in the family: Will the credit crunch tempt more litigants to adopt a McKenzie friend?” (2008) 158 New Law Journal 1739 at 1739.

R v Bow County Court Ex Parte Pelling (No 1) [1999] 4 All ER 751.

McKenzie v McKenzie [1970] 3 All ER 1034.

R v Hill [2004] 2 NZLR 145 at [54].

At [52].

A Northover and N Fisher “Keeping it in the family: Will the credit crunch tempt more litigants to adopt a McKenzie friend?” (2008) 158 New Law Journal 1739 at 1739.

The Beneficial Owners of Whangaruru Whakaturia No 4 v Warin & Ors [2009] NZCA 60, [2009] NZAR 523, at [19], citing Salmon LJ in Allen v Sir Alfred McAlpine & Sons Ltd [1968] 2 QB 229 at 226.

The Beneficial Owners of Whangaruru Whakaturia No 4 v Warin & Ors [2009] NZCA 60, [2009] NZAR 523 at [20].

At [21].

See Memorandum on Requests for the appointment of an Advocate to the Court issued by the Attorney-General and the Lord Chief Justice on 19 December 2001, Law Gazette < >.

Wanganui District Council v Tangaroa [1995] 2 NZLR 706; B v M [2006] NZSC 86. In R v Kim [2009] NZCA 294, the accused had left the country without giving instructions in relation to a criminal appeal that called his acquittal into question.

NZ Dairy Workers Union Inc v New Zealand Milk Products Ltd [2004] 3 NZLR 652 (CA).

Erwood v Maxted [2008] NZCA 139.

R v Osborne [2009] NZCA 168. Osborne pleaded guilty to murder and was sentenced to life imprisonment. He appealed, and instructed counsel but the Legal Aid Services Agency declined funding. Faced with an illiterate young man facing life imprisonment without legal representation, the Court appointed amicus curiae.

Siemer v Solicitor-General (2009) 2 NZLR 556.

Solicitor-General v Moodie HC Wellington CIV 2005-485-001026, 25 July 2006 at [19].

Levy v Victoria (1997) 189 CLR 579 at 604.

The Beneficial Owners of Whangaruru Whakaturia No 4 v Warin & Ors [2009] NZCA 60, [2009] NZAR 523.

Solicitor-General v Miss Ellis (2007) 1 NZLR 655.

The Beneficial Owners of Whangaruru Whakaturia No 4 v Warin & Ors [2009] NZCA 60 at [26].

At [25].

At [26].

Auckland Area Health Board v Attorney-General [1993] 1 NZLR 235 at 240.

At 240.

Solicitor-General v Miss Ellis (2007) 1 NZLR 655.

Duncan v Medical Practitioners Disciplinary Committee (1986) 1 NZLR 513.

R v Lee (2006) 3 NZLR 42.

Accident Compensation Corporation v Ambros (2008) 1 NZLR 340.

Section 99B(3).

Section 99C(1).

Section 99C(2) and (3).

Section 99C(4).

Judicature (Rules Committee and Technical Advisers) Amendment Act 1999, s 2.

Supreme Court Act 2003, sch 1.

Vector Ltd v Transpower New Zealand Ltd (2000) 14 PRNZ 240 at [49].

In Hosking v Runting HC Auckland CP527/02, 11 February 2003, Randerson J suggested (at [7]) that the jurisdictional basis for intervention can be found in rules 9 (dealing with cases not provided for) and 438(3) (which enables the court to make such orders and to give such directions as appear best adapted to securing the just, expeditious and economic disposal of the proceeding) of the High Court Rules.

They have also appeared 28 times in the Court of Appeal and 27 times in the High Court in this period. Interveners in the Supreme Court have included the Ngati Makino Heritage Trust (New Zealand Māori Council and others v Attorney-General [2008] NZSC 34), the International Trademark Association (Austin Nichols & Co v Stiching Lodestar [2008] 2 NZLR 14 (SC), the New Zealand Council of Trade Unions (Bryson v Three Foot Six Limited [2005] NZSC 54), and a joint intervention by the New Zealand Law Society and the New Zealand Bar Association (Chamberlains v Lai [2007] 2 NZLR 7).

Sanofi-Adventis Deutschland Gmbh v Aft Pharmaceuticals Limited HC Auckland CIV 2009-404-001795, 9 August 2011.

Human Rights Act 1993, s 5(2).

JUSTICE “To Assist the Court: Third Party Interventions in the UK” (2009) < >.

For example, in relationship property proceedings: X v X HC Auckland CIV-2006-404-903, 4 July 2006.

Recent cases include Deadman v Luxton HC Wellington CP71/99, 4 May 1999; Westhaven Shellfish Ltd v Chief Executive of Ministry of Fisheries (2002) 16 PRNZ 501 (HC); Wellington International Airport Ltd v Commerce Commission HC Wellington CP151/02 19 July 2002; Wilson v Attorney-General [Judicial Conduct] (No.2) [2010] NZAR 509.

Wilson v Attorney-General [Judicial Conduct] (No.2) [2010] NZAR 509 at [19].

See, for example, Re Rhodes [1933] NZLR 1348.

Re Northern Ireland Human Rights Commission (Northern Ireland) [2002] UKHL 25 at [32].

George Williams “The Amici Curiae and Intervener in the High Court of Australia: a Comparative Analysis” (2000) 28 FLR 365 at 372−373.

E Clark “The Needs of the Many and the Needs of the Few: A New System of Public Interest Intervention for New Zealand” (2005) 36 VUWLR 71 at 83.

E Clark “The Needs of the Many and the Needs of the Few: A New System of Public Interest Intervention for New Zealand” (2005) 36 VUWLR 71 at 72.

At 72−73.

Drew v Attorney-General [2001] 2 NZLR 428 (CA) at 432.

E Clark “The Needs of the Many and the Needs of the Few: A New System of Public Interest Intervention for New Zealand” (2005) 36 VUWLR 71 at 80.

JUSTICE “To Assist the Court: Third Party Interventions in the UK” (2009) < > at [59]-[60].

New Zealand Fire Service Commission v Ivamy (1995) 8 PRNZ 632 at 634.

JUSTICE To Assist the Court: Third Party Interventions in the UK (2009) < > at [17].

Practice Directions and Standing Orders applicable to civil appeals (approved 8 October 2007), r 37.

Supreme Court Rules 2009 (UK), r 15.

The Judicial Committee (Appellate Jurisdiction) Rules Order 2009 (SI 2009/224), r 27(1).

Supreme Court Rules 2009 (UK), r 15.

Rule 26(2).

At [13.5].

It has been suggested that this creates uncertainty and a lack of transparency: JUSTICE To Assist the Court: Third Party Interventions in the UK (2009) < > at [20].

R v Monopolies and Mergers Commission and Secretary of State for the Trade and Industry Ex Parte Milk Marque Ltd [2000] COD 329 at 330 (QB). The most authoritative judicial statement on this is from Lord Woolf in Re Northern Ireland Human Rights Commission [2002] UKHL 25 who (at [34]) stated that the determinative factor in deciding intervention applications is whether the intervention will serve the interests of justice and in particular assist the court, and that this must be balanced against any inconvenience, delay and expense of the intervention.

Rules of the Supreme Court of Canada 1974, as amended by SOR/83-930, s 1 and SOR/87-292.

Andrea Loux “Hearing a ‘Different Voice”: Third Party Interventions in Criminal Appeals” (2000) 53 Current Legal Problems 459.

Supreme Court Rules, r 61(4).

Rule 55.

Rule 57(1).

Rule 57(2)(b). This has been described this as the “most important requirement” of an intervener: J C Major “Interveners and the Supreme Court of Canada” (1999) National 27.

JUSTICE To Assist the Court: Third Party Interventions in the UK (2009) < >, citing Kenny “Interveners and Amici Curiae in the High Court” (1998) 20 Adel L R 159 at 161−167.

Levy v Victoria [1997] HCA 31.