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Intervening in the ‘Interests of Justice' in the Federal Courts

15 minute read


In a recent article, Part One of this series, I described the “(Nearly) New Approach” to interventions in Federal Court and Federal Court of Appeal proceedings. The recap, despite a recent attempt by Stratas J.A. to modernize the test for leave to intervene (Pictou Landing), the test for leave to intervene in the Federal Court and the Federal Court of Appeal remains the six factor test set in 1989 (Rothmans, Benson & Hedges). The criteria that the court will consider are: (1) Is the proposed intervenor directly affected by the outcome? (2) Does there exist a justiciable issue and a veritable public interest? (3) Is there an apparent lack of any other reasonable or efficient means to submit the question to the Court? (4) Is the position of the proposed intervenor adequately defended by one of the parties to the case? (5) Are the interests of justice better served by the intervention of the proposed third party? (6) Can the Court hear and decide the cause on its merits without the proposed intervenor?

This article explores how these factors have been interpreted and the importance of the “interests of justice” for interventions at the Federal Court and Federal Court of Appeal.


It is clear from the jurisprudence that these factors are neither cumulative nor exhaustive. The criteria are meant to be applied flexibly to account for the different factors at play in different interventions (Sport Maska). Thus, it is not necessary for a proposed intervenor to satisfy each criteria, depending on the circumstances. However, courts have placed much emphasis on the “interests of justice” factor and the requirement in Rule 109(2) that the proposed intervenor must demonstrate how its “participation will assist the determination of a factual or legal issue related to the proceeding.” The Federal Court of Appeal has held that it is “undeniable” that “the salient question is whether the intervenor will bring further, different and valuable insights and perspectives that will assist the Court in determining the matter.”

The Rules

Rule 109 of the Federal Courts Rules, Can. Reg. 98-106, sets out the authority to grant leave to intervene in a Federal Court proceeding:

109(1) Leave to intervene
The Court may, on motion, grant leave to any person to intervene in a proceeding.

109(2) Contents of notice of motion
Notice of a motion under subsection (1) shall

(a) set out the full name and address of the proposed intervener and of any solicitor acting for the proposed intervener; and

(b) describe how the proposed intervener wishes to participate in the proceeding and how that participation will assist the determination of a factual or legal issue related to the proceeding.

109(3) Directions
In granting a motion under subsection (1), the Court shall give directions regarding

(a) the service of documents; and

(b) the role of the intervener, including costs, rights of appeal and any other matters relating to the procedure to be followed by the intervener.

Interventions in the ‘public interest'

In setting out the six Rothmans, Benson & Hedges factors, Rouleau J. was specifically considering when the Court should grant standing and allow the full participation of an intervener in a “public interest” debate: at para. 12.

The six factors were applied ubiquitously by the Trial Division and the Appeal Court1 for the next two decades without revision, in cases of “public interest” debates, as considered by Rouleau J., as well as in other cases where leave to intervene is sought on other grounds.2

Interpretation of the Rothmans, Benson & Hedges factors

Beginning from the outset with Rouleau J.'s decision in Rothmans, Benson & Hedges, courts have recognized that these factors are neither exhaustive nor essential to allow an intervention. The Federal Court of Appeal has reaffirmed numerous times that it is not necessary to meet all six factors in order to justify an intervention.3 In Globalive, the court held that a genuine interest beyond a jurisprudential one and a demonstration that the proposed intervenor could assist the court were sufficient to overcome deficiencies in the other factors. Most recently, in Sport Maska, the Federal Court of Appeal confirmed, at para. 41, “the Rothmans, Benson & Hedges factors are not meant to be exhaustive” and “they allow the Court, in any given case, to ascribe the weight that the Court wishes to give to any individual factor.” On that authority, it is also possible for a proposed intervenor to go beyond the Rothmans, Benson & Hedges factors, to identify other facets which support their application for intervention. However, the court in Sport Maska indicated that the flexibility of Rothmans, Benson & Hedges factors will negate the need to go beyond them.

What does seem to be clear from the jurisprudence is that “the salient question is whether the intervenor will bring further, different and valuable insights and perspectives that will assist the Court in determining the matter.”4 The court in Sport Maska, at para. 40, accepted this observation of Stratas J.A. in Pictou Landing as “undeniable”.

After setting out the Rothmans, Benson & Hedges factors, the Federal Court of Appeal in C.U.P.E. emphasized the importance of meeting the requirement of rule 109(2). It is incumbent on the applicant to demonstrate “how the proposed intervention ‘... will assist the determination of a factual or legal issue related to the proceeding'.”5 A proposed intervenor must:

Show in its application for leave what it would bring to the debate over and beyond what was already available to the Court through the parties. Specifically, it had to demonstrate how its expertise would be of assistance in the determination of the issues placed before the Court by the parties.6

It is crucial for the applicant to go beyond mere assertion and actually demonstrate to the court how it will assist.7 To establish this, an applicant would be prudent to: identify one or more specific controlling ideas on which the case will turn, offer the submissions it will make on the controlling ideas, ensure that its submissions will not need to go beyond the evidentiary record, and distinguish its submissions from those of others already before the Court.8 Failure to do so may undermine an application for leave to appeal even where most or all of the other factors are met.

Justice Stratas also noted, sitting as a single motions judge, that the overall fairness of the intervention is a factor to be considered when determining the interests of justice. In Gitxaala Nation v. R., 2015 FCA 73, at paras. 22-23, Stratas J.A. considered the impact of allowing an intervention that might stack the deck against the respondents in the case. He held at para. 23:

These concerns are well-founded. An aspect of overall fairness in the litigation process is the “equality of arms”... To the extent possible, no one side should be so numerous or dominant that its voices drown out the other side and prevent it from expressing itself adequately.

But, as discussed below, the court is also empowered to set the terms of the intervention to take into account the equality of arms and the overall fairness of the intervention, which Stratas J.A. did in Gitxaala Nation by restricting the length of written and oral argument the proposed intervenor was entitled to make.

A proposed intervenor should, therefore, be prepared to justify its intervention in terms of the overall fairness of its participation in the litigation.

Insufficient for Intervention

The courts have also espoused and repeated a number of factors which would be insufficient to meet the test for leave to intervene. Foremost among these comments is that an interest in the outcome of the litigation that is purely jurisprudential is insufficient to justify intervention.9

The courts have also been loath to allow intervention for piggybacking purposes. In Li v. Canada (Minister of Citizenship and Immigration), 2004 FCA 267, the Court of Appeal stated that an intervention will not be allowed to allow an intervenor to merely support position of one party by repeating that party's arguments in the intervenor's own words. Similarly, in Canada (Attorney General) v. Siemens Enterprise Communications Inc., 2011 FCA 250, the Court of Appeal commented that Rule 109 was “not to be used in order to replace a respondent by an intervener”.

Additionally, the Court of Appeal has held that where a potential intervenor will suffer no potential prejudice by not participating because one of the parties owes them a duty to protect their interests, leave may not be granted.10

Note that this brief description is not exhaustive of the cautions which the courts have given in relation to interventions. They are included to provide further guidance on how best to frame an application for intervention. Most particularly, where the dominant interest in intervening might actually be jurisprudential, or to support the arguments of one of the parties (i.e. an individual landowner or citizen challenging environmental contamination or legislation), it is crucial to bring some other arguments to bear on the application for leave to intervene.

Miscellaneous Points on Practice and Procedure

In addition to guidance on the test for leave to intervene and the interpretation and application of the Rothmans, Benson & Hedges factors, the courts have issued a handful of procedural and practice directions regarding interventions. In no particular order, this section briefly describes these directions.

An intervenor is bound by terms of intervention and no right to appeal unless ordered or leave granted,11 but the court is not obliged to give complete set of instructions governing the intervenor's role at the time of intervention.12 Still, an intervenor's pleadings may be struck if they go beyond what is allowed by the court's order granting leave to intervene.13

Additionally, any intervenors must take the record as they find it14 and may not litigate new issues.15 But, consistent with the essential requirement that a proposed intervenor assist the court, the intervenor must add some legal or factual argument on the basis of that record.16 And, in certain circumstances, a public interest intervenor can raise related issues of public interest which naturally arises on the record even if they have not been raised by the parties.17

In relation to appeals, the Federal Court of Appeal has commented that where leave to intervene is granted at trial, leave should also be granted on appeal, barring a fundamental error in the decision granting leave, some material change in the issues on appeal, or important new facts bearing on the intervention.18 On appeal, an intervenor must take the case as they find it and cannot, to the prejudice of the parties, argue a new issue that requires the introduction of new evidence.19 Along those lines, leave will not be granted for the purpose of arguing an issue not raised at trial or proposed by the parties to be raised on appeal.20

Moreover, the court has indicated on multiple occasions that a proposed intervenor has a duty to make its motion to intervene as early as possible in order to minimize the disruption in the proceedings in which it seeks to participate.21 Where a potential intervenor could have sought leave to intervene in proceedings below and intends to range far from issues raised by the parties, leave will not be granted.22

The content contained in these blogs is intended to provide information about the subject matter and is not intended as legal advice. If you would like further information or advice on any of the subjects discussed in a blog post, please contact the author.

1But see Federation of Saskatchewan Indians v. Canada (A.G.), 2002 FCT 1001 where the court held at para. 10:

the test for allowing intervener standing for argument at the appellate level is necessarily different from that which is used at trial; trials must remain manageable and the parties must be able to define the issues and the evidence on which they will be decided. An appellate court on the other hand deals with a pre-established record that is not normally subject to change. And an appellate court, while benefiting from the different viewpoints expressed by interveners, is far better equipped to limit and control the length and nature of their interventions.

This approach does not appear to have been picked up in subsequent case law.

2For example, to protect a private interest of the proposed intervenor.

3See e.g., Canadian Pacific Railway v. Boutique Jacob Inc., 2006 FCA 426, at paras. 19-21; Globalive Wireless Management Corp. v. Public Mobile Inc., 2011 FCA 119.

4Pictou Landing, at para. 9.

5C.U.P.E. v. Canadian Airlines International Ltd., [2000] F.C.J. No. 220 (Fed. C.A.), at para. 9.

6Ibid, at para. 12.

7Forest Ethics Advocacy Association v. Canada (National Energy Board), 2013 FCA 236.

8Canada (Minister of Citizenship and Immigration) v. Ishaq, 2015 FCA 151.

9C.U.P.E., at para. 11; Amnesty International Canada v. Canada (Chief of Defense Staff for Canadian Forces, 2008 FCA 257; Canada (Prime Minister) v. Khadr, 2009 FCA 186; R. v. Boulton, [1976] 1 F.C. 252 (C.A.); Tioxide Canada Inc. v. R. (1994), 174 N.R. 212 (Fed. C.A.).

10Imperial Oil Resources Ltd. v. Canada (Minister of Indian Affairs & Northern Development) (1998), 234 N.R. 83 (Fed. C.A.).

11Merck Frosst Can. Inc. v. Canada (Min. of National Health & Welfare) (1997), 72 C.P.R. (3d) 187 (Fed. C.A.); Edmonton Friends of the North Environmental Society v. Canada (Min. of Western Economic Diversification), [1991] 1 F.C. 416 (C.A.).

12Sawridge Band v. Canada, 2001 FCA 341.

13Misquadis v. Canada (Attorney General), 2003 FCA 370.

14Edmonton Friends of the North Environmental Society, at paras. 8, 12.

15Maurice v. Canada (Minister of Indian Affairs & Northern Development) (2000), 183 F.T.R. 45 (T.D.).

16Canada (Attorney General) v. P.I.P.S.C., 2010 FCA 217.

17Benoit v. Canada, 2001 FCA 71; Eli Lilly Canada Inc. v. Canada (Minister of Health), 2001 FCA 108.

18Canada (Attorney General) v. Friends of the Canadian Wheat Board, 2012 FCA 114.

19Mikisew Cree First Nation v. Canada (Minister of Canadian Heritage), 2004 FCA 66.

20International Fund for Animal Welfare Inc. v. Canada (Minister of Fisheries & Oceans), [1988] 3 F.C. 590 (C.A.); but see Benoit v. Canada.

21Siemens; ViiV Healthcare ULC v. Teva Canada Ltd., 2015 FCA 33.

22Imperial Oil.

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