Mathur et al: Youth climate litigation against Ontario government found to be justiciable but dismissed for failing to establish charter violations

April 20, 2023 | Christie A. McLeod, Annafaye Dunbar, Rosemarie Sarrazin

On April 14, 2023, the Ontario Superior Court (the “ONSC”) released its highly-anticipated decision in Mathur et al v His Majesty the King in Right of Ontario [Mathur et al] in which it held that, although the Application raised justiciable issues, the Applicants had not established any violations of sections 7 and 15 of the Canadian Charter of Rights and Freedoms (the “Charter”) and dismissed the Application.[1]

The lawsuit, initially filed in late 2019 by Ecojustice and seven youth environmental activists against the government of Ontario, challenged the constitutionality of the government’s weakened 2030 greenhouse gas emissions (“GHG”) reduction target. The target was set pursuant to the Ontario government’s adoption of the Cap and Trade Cancellation Act (the “Cancellation Act”) in 2018, which repealed the Climate Change Mitigation and Low-carbon Economy Act and nullified the emissions reduction target it had set out for Ontario to reduce its emissions by 45 percent below 2005 levels by 2030. The Cancellation Act set a new and substantially weaker target of reducing emissions in Ontario by 30 percent below 2005 levels by 2030 (the “Ontario Target”). The Applicants argued, among other things, that the adoption of the Ontario Target was insufficient to effectively combat climate change, such that it violated the rights of Ontario youth and future generations under sections 7 (life, liberty and security of the person) and 15 (equality) of the Charter. The applicants specifically sought:

  • a declaration that the Ontario Target was unconstitutional;
  • a declaration that sections 3(1) and/or 16 of the Cancellation Act were unconstitutional;
  • an order directing Ontario to set a revised science-based target consistent with its share of the minimum level of emissions reduction needed to limit change in accordance with the commitments made under the Paris Agreement; and
  • an order directing Ontario to revise its climate change plan under section 4(1) of the Cancellation Act after setting a revised target.[2]

In response to the Application, the Attorney General of Ontario brought a motion to strike the claim on the grounds that the issue was not justiciable (i.e. not suitable for judicial determination). Justice Brown denied this motion for the ONSC in Mathur v. Ontario, finding that the application was prima facie justiciable.[3] The case was then heard on its merits in September 2022. The Mathur et al case was the first climate lawsuit based on the Charter to reach a full hearing and be heard on its merits in any Canadian court.

Justiciability hurdle overcome

Justice Vermette first considered whether the case was justiciable and concluded that the Charter issues raised by the Applicants were challenging specific state action and legislation and were thereby justiciable.[4] She noted, however, that the issue of determining Canada and Ontario’s “fair” shares of the remaining carbon budget was an issue “that should be determined in another forum” and was not a justiciable matter.[5]

Justice Vermette’s finding that the Mathur et al claim was justiciable mirrored a recent finding from Justice Basran at the BC Supreme Court in Sierra Club of British Columbia Foundation v British Columbia (Minister of Environment and Climate Change Strategy) [Sierra Club].[6] In this case, the Sierra Club of British Columbia Foundation (“Sierra Club of BC”) sought a declaratory judgment that the Minister of Environment and Climate Change Strategy (the “Minister”) had breached its statutory obligations to prepare an annual climate accountability report pursuant to the Climate Change Accountability Act, SBC 2007, c. 42 (“CCAA”) by failing to include plans to continue progress towards achieving the 2025, 2040, 2050, and oil and gas sector targets in its reporting materials.

Justice Basran concluded that as the reporting requirements of the CCAA were sufficiently clear and could be enforced by the courts, the Minister’s compliance with the reporting requirements of the CCAA was a justiciable issue. Here, Justice Basran noted that if the Sierra Club of BC had sought to evaluate whether the policies would reduce emissions and achieve the targets identified by the Minister, this would not have been a justiciable issue.[7] Despite this finding of justiciability, the Court held that the CCAA did not require the Minister to include specific percentages of target achievement and found that the Minister had complied with its statutory reporting obligations under the CCAA and denied Sierra Club of BC’s petition.[8]

While neither Mathur et al or Sierra Club were successful on the merits, the findings of justiciability were a significant departure from the line of climate cases in Canadian courts which have been preliminarily dismissed on this procedural ground.

In La Rose v Canada [9] (which we wrote about in a previous issue), a group of fifteen Canadian youth alleged that Canada was:

  • continuing to cause, contribute to, and allow a level of GHG emissions that is incompatible with a stable climate system;
  • adopting GHG emission targets that failed to match the level of ambition dictated by the best available climate science;
  • failing to meet Canada’s GHG emission targets; and
  • actively participating in and supporting the development, expansion and operation of high-emitting industries and activities involving fossil fuels.

The plaintiffs argued that the cumulative effects of GHG emissions occurring from Canada’s conduct unjustifiably infringed their rights to life, liberty and security, as well as equality, under sections 7 and 15, respectively, of the  Charter, and sought several orders which they claimed would collectively require the Defendants to “comply with their common law and constitutional obligations and act in a manner compatible with maintaining a Stable Climate System.”[10]

Canada successfully brought a motion to strike the plaintiffs’ Statement of Claim on the basis that neither Charter claim was justiciable. The test on a motion to strike is whether it is plain and obvious that the pleadings disclose no reasonable cause of action, or that the claim has no reasonable prospect of success.[11] The pleadings must be read as generously as possible, and the matter must proceed to trial where a reasonable prospect of success exists.[12]

While in Mathur et al, the plaintiffs challenged a single law and an accompanying target, in La Rose, the plaintiffs challenged the entirety of Canada’s alleged conduct related to GHG emissions, and asked the Court to assess the cumulative effects of GHG emissions occurring from that conduct.[13] Justice Manson found that the plaintiffs failed to plead a definable law, state action in issue, or a network of same,[14] concluded that the Charter claims were not justiciable, and found that the public trust doctrine, while justiciable, did not disclose a reasonable cause of action.[15] The plaintiffs filed an appeal with the Federal Court of Appeal in November 2020, arguing that the trial judge erred in finding no reasonable cause of action and in dismissing the claim without providing the plaintiffs an opportunity to amend their claim. Their appeal was heard this past February, and a judgment has not been rendered at this time.

Another climate litigation claim was initiated by two hereditary Chiefs of an Indigenous Nation in BC against the federal government in Misdzi Yikh v Canada [Misdzi Yikh].[16] In this claim, the Chiefs alleged, among other things, that the federal government’s failure to enact more stringent policies to reduce GHG emissions by 2030 was contrary to various common law principles and violated the rights of the Applicants under sections 7 and 15 of the Charter. The Applicants also argued that the federal government had breached its duty to ensure low GHG emissions under its Peace Order and Good Governance power under section 91 of the Constitution Act, 1982.

Similar to La Rose, the federal government brought a motion to strike and the Federal Court considered whether the claims advanced by the Applicants were justiciable. The Court found that neither the claims alleged or the remedies sought were justiciable, as the claim did not impugn or seek relief under any specific federal law as being responsible for the alleged Charter breaches.[17] The Applicants appealed to the Federal Court of Appeal and their appeal was heard concurrently with La Rose this past February; a judgment has not yet been rendered.

While the Ontario Court of Appeal has recognized that a network of laws can be the basis for a constitutional violation,[18] the climate litigation cases brought in Canada to date illustrate the difficulties in establishing the justiciability of such. Mathur et al and Sierra Club indicate the court’s willingness to consider issues of climate accountability, however, should this preliminary procedural hurdle be overcome.

Section 7 analysis

The brunt of Justice Vermette’s analysis in Mathur et al considered the Applicants’ claim that their section 7 Charter rights were violated. She remarked that while it was “indisputable” that the Applicants (and Ontarians in general) were “experiencing an increased risk of death and an increased risk to the security of the person” as a result of climate change, the appropriate question to consider was whether the Ontario Target and the impugned sections of the Cancellation Act specifically imposed an increased risk of death or negatively impacted or limited the Applicants’ security.[19]

Based on the nature of the Applicants’ claim, Justice Vermette found that this question raised the issue of whether section 7 of the Charter imposed positive obligations on the state. This was a departure from the Applicants’ position that they were not advancing positive rights as the government’s degree of involvement in authorizing, incentivizing, facilitating, and creating a level of dangerous GHG emissions, as well as its regulation of overall GHG levels in the province, triggered an obligation to ensure the resulting scheme was constitutionally compliant.20

To date, a freestanding positive obligation to ensure each person enjoys section 7 Charter rights has not been imposed on the state. On this point, Justice Vermette opined as follows:

In my view, the Applicants make a compelling case that climate change and the existential threat that it poses to human life and security of the person present special circumstances that could justify the imposition of positive obligations under section 7 of the Charter.[21]

Justice Vermette declined to make a decision on whether positive obligations are imposed under section 7 in this case, however, due to her conclusion that any deprivation of section 7 Charter rights were not contrary to the principles of fundamental justice.

The Applicants’ had claimed that the Ontario Target violated the principles of fundamental justice against arbitrariness and gross disproportionality. With respect to arbitrariness, the Applicants defined the province’s objective as doing its share to reduce emissions and protect the environment for future generations. Justice Vermette disagreed with this framing, stating that the objective of the Ontario Target was “to reduce GHG in Ontario to address and fight climate change”.[22] She held that the Ontario Target and its effects were connected to this objective and were thereby not arbitrary. As the Applicants supported this objective (and simply wanted Ontario to pursue the objective more aggressively), she also held that the principle of gross disproportionality was not infringed.[23]

Section 15 analysis

The Applicants claimed that the Ontario Target, in its effects, created a distinction based on the enumerated ground of age, as it imposed distinct burdens on different Ontarians based on their age and their date of birth.[24] The Applicants recognized that the Ontario Target and the Cancellation Act did not distinguish between Ontarians of different ages, but noted that youth and future generations will be impacted more acutely and more substantially due to their age. The Applicants chose not to advance a particular age cut-off or eligibility requirement.

Justice Vermette held that the Applicants failed to demonstrate that the Ontario Target created a distinction based on an enumerated or analogous ground, finding that youth are disproportionately impacted by climate change and not the Ontario Target or the Cancellation Act. She adopted the province’s argument that the worsening of climate change’s impacts are not caused by the Ontario Target and will not be borne by a distinction based on age, but rather by a temporal distinction, and concluded that the Applicants did not establish any violation of section 15(1) of the Charter.

Mathur et al was not the first climate litigation suit in Canada to argue that young persons’ Charter rights are violated by a government’s failure to set a sufficiently strong emissions target. In Environnement Jeunesse c. Procureur général du Canada,[25] non-profit organization Environnement Jeunesse (“ENJEU”) sought authorization to file a class action against the federal government on behalf of all residents of the province of Québec aged 35 and under (as of November 26, 2018).

ENJEU alleged gross negligence and inaction by the government towards the dangers posed by climate change, claiming that the federal government violated young persons’ Charter rights by failing to set a GHG emissions target sufficient to avoid dangerous climate change impacts and by failing to have an adequate plan to meet its target. The Superior Court of Québec rejected the application on the basis that the proposed class, with a cut-off age of 35, was arbitrary and not objective.[26] The Court also found that, in this case, a claim commenced by a single person would have the same effect as the proposed class action, and therefore a class action was not the appropriate procedural vehicle.[27] The Québec Court of Appeal (“QCCA”) confirmed the Superior Court’s decision not to certify the proposed class action. [28]

Takeaways & Conclusion

The Supreme Court of Canada has acknowledged that the climate crisis “poses a grave threat to humanity’s future,”[29] and the federal government, as well as 600+ Canadian municipalities, have declared climate emergencies.[30] Despite these recognitions, governments in Canada (both provincially and federally) continue to set significantly less ambitious emissions reduction targets than required to comply with the scientific consensus published in 2018 and accepted by Justice Vermette that GHG emissions must be reduced by approximately 45 percent below 2010 levels by 2030 and reach net zero by 2050 in order to limit global average surface warming to 1.5?C.[31]

For Ontario to meet this global goal, Justice Vermette noted that Ontario would need to reduce its emissions by approximately 52 percent below 2005 levels by 2030, i.e., increase the Ontario Target by 22 percent.[32] Given that Canada is the tenth-highest GHG emitting country/region globally,[33] many also believe that Canada and other high-emitting states ought to shoulder a larger share of the global mitigation burden, which would require Ontario, the other provinces/territories, and Canada to set – and meet – emissions reduction targets which are even more stringent than this global goal.

To date, applicants seeking to hold governments in Canada accountable for climate action and inaction through the courts have struggled to craft a claim that is both specific enough to be found justiciable and broad enough to encapsulate state conduct that establishes a violation of a Charter right.

In La Rose, the plaintiffs challenged Canada’s climate actions and inactions without targeting a specific law or state action. The Federal Court found that the action was not justiciable due, in part, to the “undue breadth and diffuse nature” of the impugned conduct.[34] In Environnement Jeunesse, the Superior Court of Québec found that the applicant had raised a justiciable issue, however, the QCCA overturned this finding and held that the application raised questions that overstepped the court’s reach.[35]

In Mathur et al, the Applicants made “the strategic choice” to challenge only the Ontario Target and sections of the Cancellation Act, which led to a successful finding on justiciability, but prohibited the analysis from shifting to consider other state actions.[36] As such, in her consideration of the principles of fundamental justice, Justice Vermette was limited to an analysis of the Target and the sections of the Cancellation Act.

Citizens in other jurisdictions have found success in the courtroom for compelling stronger emissions reduction targets. In the Netherlands, the Urgenda Foundation successfully claimed that the Netherlands government had breached its duty of care towards its citizens by failing to adopt a sufficient emissions reduction target.37 The Hague District Court found that the national emissions reduction target—to reduce emissions by 17 percent below 1990 levels by 2020— was insufficient, as it did not meet the established target set out by the IPCC for ‘developed’ countries to reduce emissions by 25 to 40 percent below 1990 levels. The government was ordered “to limit the joint volume of Dutch annual greenhouse gas emissions … by at least 25% at the end of 2020 compared to the level of the year 1990”.[38] This decision was upheld by the Hague Court of Appeal and the Supreme Court of the Netherlands.[39]

In Germany, a group of youth successfully filed a legal challenge against Germany’s Federal Climate Protection Act, arguing that its target of reducing GHG emissions by 55 percent below 1990 levels by 2030 was insufficient and failed to consider Germany (and the European Union’s) obligations under the Paris Agreement.[40] The youth alleged violations of their constitutionally-protected rights to human dignity and life and physical integrity, as well as the failure of the government to bind the political process to protect the natural foundations of life in responsibility for future generations.

The Federal Constitutional Court struck down parts of Germany’s climate legislation as incompatible with the Applicants’ rights on the basis that the law failed to set sufficient provisions to reduce emissions beyond the year 2030. In a significant finding, the Court held that the legislature had not proportionally distributed the limited carbon budget between present and future generations, stating that “one generation must not be allowed to consume large portions of the CO2 budget while bearing a relatively minor share of the reduction effort, if this would involve leaving subsequent generations with a drastic reduction burden and expose their lives to serious losses of freedom”.[41] The Court ordered the government to set clear emissions reduction targets for the years 2031 onward.

These international victories provide hope to future claimants that climate litigation suits in Canada seeking to hold our governments accountable will also find success in the courtroom. While the Applicants in Mathur et al were not successful in this instance, they have indicated that they will be appealing Mathur et al to the Ontario Court of Appeal.[42] As this challenge continues through the courts, and the decisions in the appeals of La Rose and Misdzi Yikh are drafted, we look forward to seeing how subsequent climate litigation in Canada learns from these existing claims and builds upon the precedents established to continue pushing for adequate government responses to the climate crisis.

Should you have any questions or concerns, please feel free to reach out to a member of Miller Thomson’s ESG and Carbon Finance group.

Mark your calendars for Wednesday, May 10, 2023, our ESG and Carbon Finance group will be hosting a panelist discussion on Sustainable Finance. The event will be held in-person at our Montreal office and will be broadcasted virtually for those who wish to dial-in. To learn more about the event, please click here.

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[1] 2023 ONSC 2316 [Mathur et al], at para. 96.

[2] Ibid, at para. 2.

[3] 2020 ONSC 6918. Leave to appeal was also denied by the Ontario Divisional Court, see 2021 ONSC 1624.

[4] Mathur et al, at para. 106.

[5] Ibid, at para. 109.

[6] 2023 BCSC 74.

[7] Ibid, at paras. 43 to 48.

[8] Ibid, at paras. 68, 81, and 82.

[9] 2020 FC 1008 [La Rose].

[10] Ibid, at para. 20.

[11] Hunt v Carey Canada Inc, [1990] 2 SCR 959 at 980; R v Imperial Tobacco Canada Ltd, 2011 SCC 42 at para 17.

[12] Imperial Tobacco at para 21.

[13] La Rose, at paras. 3, 39.

[14] Ibid, at para 46.

[15] Ibid, at para. 102.

[16] 2020 FC 1059

[17] Ibid, at paras. 72-73, 115.

[18] See Tanudjaja v Canada (Attorney General), 2014 ONCA 852.

[19] Mathur et al, at para. 120.

[20] Ibid, at para. 52.

[21] Ibid, at para. 138.

[22] Ibid, at para. 158.

[23] Ibid, at paras. 153-62.

[24] Ibid, at para. 68.

[25] 2019 QCCS 2885 [Environnement Jeunesse 2019]. See also: Environnement Jeunesse c. Procureur général du Canada, 2021 QCCA 1871 [Environnement Jeunesse 2021] Environnement Jeunesse c. Procureur général du Canada, 2022 CanLII 67615 (CSC).

[26] Environnement Jeunesse 2019, at paras. 123, 135.

[27] Ibid, at para. 141.

[28] Environnement Jeunesse 2021..

[29]References re Greenhouse Gas Pollution Pricing Act, 2021 SCC 11, at para. 2.

[30] “Vote No. 1366”, 42nd Sess, Sitting No. 435 (17 June 2019), online: House of Commons Canada <>; Guilherme Baggio and Laura Tozer, “Moving Canadian municipalities to the forefront of decarbonization” (25 January 2023), online: Policy Options .

[31] Mathur et al, at para. 20. This scientific consensus was reported by the United Nations’ Intergovernmental Panel on Climate Change (“IPCC”) in a 2018 special report. Since this time, the IPCC has produced additional reports which call for stronger climate action.

[32] Mathur et al, at para. 21.

[33] Government of Canada, “Global Greenhouse Gas Emissions” (last modified 25 August 2022), online: .

[34] La Rose, at para. 41.

[35] Environnement Jeunesse 2021, at paras. 40 to 42.

[36] Mathur et al, at para. 135.

[37] Urgenda v Government of the Netherlands (Ministry of Infrastructure and the Environment (24 June 2015) C/09/00456689 (English translation) (Netherlands) at 3.1 [Urgenda]

[38] Ibid, at 5.1.

[39] ECLI: NL: HR: 2019: 2007

[40] Neubauer et al v Germany, 1 BvR 2656/18; 1 BvR 78/20; 1 BvR 96/20; 1 BvR 288/20.

[41] Ibid, at para. 192.

[42] Ecojustice, “Statement: Ontario youth undeterred in legal fight to hold Ontario government accountable for climate action” (18 April 2023), online: .


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