The Constitutional Crisis within the Climate Crisis

“[C]limate change is an existential challenge. It is a threat of the highest order to the country, and indeed to the world. ... The undisputed existence of a threat to the future of humanity cannot be ignored.”

- References re Greenhouse Gas Pollution Pricing Act (2021)[1]

In the References re Greenhouse Gas Pollution Pricing Act (“GGPPA Reference”), the Supreme Court of Canada used unequivocal language to characterize the “global climate crisis.”^[2] Their message was clear: climate change is not a matter of political opinion but is a pressing and unprecedented threat. Yet, in the years following the judgment, Canadian courts have largely failed to treat climate change with the urgency the Supreme Court gave it. In their reluctance, the courts may have identified the fire (both metaphorical and literal) but have left it to burn.

A central challenge in holding governments accountable for environmental harm lies in how we frame constitutional rights, particularly with regard to the distinction between negative and positive obligations. At its core, this distinction requires us to ask whether the state’s role is simply to refrain from infringing on rights (negative obligations), or whether it must take active steps to fulfill them (positive obligations). Positive rights are often viewed as contentious because they invite courts to scrutinize and potentially reshape complex political decisions, including decisions on the allocation of finite and perhaps even scarce resources — territory traditionally left to legislatures.

When it comes to climate litigation under the Charter of Rights and Freedoms (“Charter”), Canadian courts have so far been hesitant to recognize positive obligations, echoing an overall (but inconsistent) reluctance in all areas of Charter jurisprudence.^[3] But climate change, and the language used by the Supreme Court to describe it, demands that a broader and more responsive approach is required, given the scale of the harms at stake. In turn, climate litigation may require the courts to rethink traditional boundaries of judicial restraint.

The Legal Landscape: An Evolving Framework

The Supreme Court of Canada has yet to decide an environmental case under the Charter, leaving lower courts to cautiously chart this evolving terrain. This doesn’t necessarily mean that our apex court has been silent on environmental rights issues, however. The GGPPA Reference of 2021 illustrates the Court’s willingness to recognize the gravity of the climate crisis. Although the decision was grounded in federalism, not the Charter, the majority of the Court confirmed that “climate change is real … and it poses a grave threat to humanity’s future.”^[4] While the majority stopped short of recognizing a freestanding constitutional right to environmental protection, which was never on the cards in that case, its reasoning nevertheless lays important groundwork: it signals the idea that the judiciary has some role, however limited, in ensuring governments take the crisis seriously.

Apart from the GGPPA Reference, Canadian courts have historically been opposed to intervening in matters related to Canada’s international climate change obligations, viewing them as political, rather than legal, issues.^[5] More recently, however, two Charter challenges, La Rose v Canada and Mathur v Ontario, have illustrated a shift in how courts can engage with climate litigation.^[6] While still constrained by concerns over procedural hurdles and the proper institutional role of courts, these cases signal a cautious evolution in the courts’ willingness to consider the constitutional dimensions of the climate crisis.

In La Rose, the Federal Court of Appeal considered the combined appeal of two Charter claims brought by groups of child and Indigenous appellants, respectively.^[7] These appellants argued that the federal government’s inadequate approach to its international climate commitments violated sections 7 and 15 of the Charter.^[8] Departing from previous decisions, the Court held that the claims were justiciable and could be argued. The section 15 claim was struck outright, as it was framed around future harms and intergenerational equity, which are not yet recognized in Canadian jurisprudence. The section 7 claim, however, was struck with leave to amend, so the appellants could identify a specific state action to challenge. The amended claims will be heard by the Federal Court in the fall of 2026.

In Mathur, a group of young climate rights activists challenged the Ontario government’s decision to lower its climate emissions reduction target, arguing that the rollback of protection violated their Charter rights. They sought a declaration that sections 7 and 15 had been infringed, along with an order requiring the government to adopt a science-based emissions reduction target in line with international standards. This was the first climate Charter case to be deemed justiciable and to proceed to trial on the facts, although Ontario Superior Court dismissed both arguments because it was deemed that they effectively sought recognition of a positive right.^[9]

On appeal to the Ontario Court of Appeal, however, the litigants were partially successful. The Court stated that by enacting a legislative scheme to address greenhouse gas emissions, the Ontario government had voluntarily assumed an obligation which it could not retreat from without facing constitutional scrutiny. The Ontario government unsuccessfully appealed the decision to the Supreme Court, and the case will be reheard at the trial level for a complete evidentiary hearing in December 2025.^[10] 

Read together, the Supreme Court’s analysis in the GGPPA Reference and the broader judicial treatment of climate-based Charter claims raises a pressing question: if the courts accept that the climate crisis is real, human-caused, and demands coordinated national action, why are they so hesitant to define the constitutional obligations of governments to respond? This hesitation shows that while courts are willing to acknowledge the severity of the crisis, they remain wary of stepping too far into what they perceive as the domain of policy-making, with Charter interpretation in environmental cases ending up shaped by institutional self-restraint rather than the pull of legal doctrine or principle.

The result is that while courts focus on their own institutional limits, they fail to address important questions about when government neglect and inaction might become so consequential and destructive that it can’t be reconciled with our constitutional commitments. As Bankes et al put it, “the question at the heart of climate change litigation is the question of whether it is lawful for governments to sit on their hands or to prescribe half-hearted measures.” 

The Limits of Judicial Deference in Climate Justice

Environmental rights occupy a unique space within the broader category of positive rights.  For example, Stepan Wood highlights the flaw of equating the state’s role in climate change with its involvement in other social issues (e.g. poverty, homelessness), given that the state actively permits activities that exacerbate the climate crisis.^[11] The climate crisis is further complicated by its temporally and spatially diffuse impacts. This means that governments can choose to deflect responsibility by presenting themselves as just one part of a larger puzzle, risking collective inaction. More troubling, however, is that governments can roll back climate initiatives or fail to meet their own targets because any sort of action is seen as a policy choice, and not a constitutional requirement.

The tension around government responsibility ignites a recurring theme in climate change litigation, specifically of whether claimants are seeking recognition of a positive right to environmental protection. This is viewed as empowering courts to mandate specific policies aimed at mitigating climate harms. But the language used in judgements to determine whether a right being sought is positive or negative in nature is convoluted and often does more harm than good.

The Mathur decision illustrates the complications inherent within this binary framework. The Court of Appeal corrected the lower court’s judgment that the applicants were seeking a positive right, clarifying instead that the Ontario government had undertaken a positive statutory obligation (i.e. setting emissions targets), which made its climate policy subject to Charter scrutiny. The Court appeared more comfortable finding a Charter breach only because the government had already expressed a legislative intent to act in a particular way. Absent that intention, there could be no constitutional obligation to adopt meaningful climate policy. But this distinction feels arbitrary. As Emmett Macfarlane asks, “how could it possibly be the case that the Charter says nothing about the harms of doing nothing, but it does activate at the level of not doing enough?”^[12] 

These concerns are reflective of an overarching question that courts and the public continually struggle with: where do we draw the line between legitimate judicial oversight and judicial overreach into the realm of political decision-making? A positive right to environmental protection under the Charter implies that courts could compel governments to take specific measures to safeguard the environment — potentially encroaching into the policy-making domain traditionally reserved for democratically elected officials and policy experts, i.e. those with the mandate and/or expertise to tackle such complex issues. While this prospect raises legitimate concerns about judicial intervention, these concerns are about the extent of judicial involvement, not about the nature of the right itself.

However, in a world facing a climate crisis, one that the Supreme Court has already addressed with unequivocal urgency, it becomes increasingly difficult to rely on the age-old debate about the institutional limits of courts. Clinging to this argument risks granting legislatures unchecked power to delay or weaken climate action. As Martin Olszynski and his co-authors point out, there is a striking difference between how governments approach climate change in courts of law versus in courts of public opinion.^[13] While governments do not contest climate change and the need for initiatives when faced with legal action, their divisive political rhetoric seems to suggest otherwise. To quote Olszynski et al again: “Charter-based climate litigation might be best understood as simply requiring governments to walk the talk of their political rhetoric.”^[14]

If both courts and governments accept the reality of the crisis, then judicial deference becomes harder to justify. Without any constitutional guardrails, political rhetoric — and the policy choices that result — can continue unchecked so that climate action is left unexamined and unaccountable.

Reframing the Fear of Judicial Intrusion

When looked at closely, the concern for judicial intrusion falls apart because climate litigation does not embolden courts beyond what they have already been doing. In the Mathur decision, the Court of Appeal acknowledged that requiring the government to adopt a science-based emissions standard would not be overly intrusive. Compared to earlier decisions by the Supreme Court, this is arguably much less intrusive than what courts have done in prior judgements related to policy-making.^[15] For example, in Carter v Canada, the Supreme Court struck down the Criminal Code prohibition on physician-assisted dying, significantly affecting health policy.^[16] In Canada v Bedford, several provisions of the Criminal Code regarding sex work were invalidated.^[17] These cases are only a few, but demonstrate a deeper intrusion into policy-making traditionally reserved for legislatures. In contrast, requiring climate policy to adhere to an internationally recognized, science-based standard for greenhouse gas emissions involves less judicial interference because it demands that government decisions be informed by credible evidence rather than prescribing specific policies.

Moreover, the positive/negative rights dichotomy that courts have repeatedly used to limit their own power often overlooks a crucial feature of the Charter: the section 1 safety valve, which allows governments to justify limits on Charter rights if those limits meet the section 1 (Oakes) test.^[18] Section 1 matters because even if courts were to recognize that an environmental right has been infringed (whether framed negatively or positively), governments could still explain and defend their actions in open court. The government can always argue that a policy in question, such as a large industrial project approval, has a pressing and substantial objective such as economic development or job creation. Governments can also show that they impaired the right in question as little as possible and built in mechanisms to minimize the damage to the environment. And at the final stage of proportionality, courts are able to weigh the harm to constitutional rights against the policy’s benefits, reinforcing a measured and deferential approach that gives ample leeway to governmental discretion and legitimate priority setting.

In other words, section 1 is already built into the Charter to protect against judicial overreach by maintaining space for the legislature to respond within its constitutional role. It is designed to uphold legislative supremacy and address concerns about judicial restraint, all while fostering an ongoing dialogue between courts and governments. So if judicial power is already limited by section 1 (and other shields like the notwithstanding clause) then the real question should not be about overreach. Rather, when addressing the climate crisis, the focus should be on whether courts are doing enough to tackle a grievous problem that demands an all-hands-on-deck approach. Excessive deference to governments that allow inadequate climate policies, without addressing the substantive concern raised in prior judgments (i.e. the expansive and destructive force of the climate crisis), reflects judicial restraint taken too far.

Conclusion

Courts cannot call climate change a crisis and then leave it open to be treated like a debate.

Despite widespread recognition of the issue’s urgency, climate change remains deeply politicized, and in jurisdictions where economic interests tend to be prioritized over environmental concerns, meaningful climate policy may never top the ballot. It is therefore inconsistent for courts to recognize the universality and urgency of the climate crisis while simultaneously entrusting the response to governments without any constitutional guardrails. To be effective, courts must move beyond mere recognition of a crisis and play an active role in ensuring governments are held accountable for the climate action they undertake. The climate crisis is not a slow-moving debate that calls for judicial restraint and adherence to classical models of institutional boundaries. Rather, it is a raging wildfire demanding that courts pick up the hose and help put it out.

***

Areeba Ismail was a summer student at the Centre for Constitutional Studies in 2025, and is currently a 3L law student at the University of Alberta

^[1] References re Greenhouse Gas Pollution Pricing Act, 2021 SCC 11 at para 167 [GGPPA Reference].

^[2] Ibid.

^[3] Canadian Charter of Rights and Freedoms, Part I of the Constitution Act, 1982, being Schedule B to the Canada Act 1982 (UK), 1982, c 11 [Charter]. 

^[4] GGPPA Reference, supra note 1 at para 2.

[5] See Friends of the Earth v Canada (Governor in Council), 2008 FC 1183 and Turp v Minister of Justice and Attorney General of Canada, 2012 FC 893, where the courts held that compliance with the Kyoto Protocol and decisions about treaty withdrawal fell under executive discretion and were not justiciable. Similarly, in Environnement Jeunesse c Procureur général du Canada, 2021 QCCA 1871, a climate change class action was denied as courts found the issue justiciable but inappropriate for judicial interference, deferring to the legislature’s policy-making role.

[6] La Rose v Canada, 2023 FCA 241 [La Rose]; Mathur v Ontario, 2024 ONCA 762 [Mathur].

[7] La Rose v Canada, 2020 FC 1008; Misdzi Yikh v Canada, 2020 FC 1059.

[8] Charter, supra note 2, ss 7, 15.

[9] Mathur v His Majesty the King in Right of Ontario, 2023 ONSC 2316.

[10] Mathur v Ontario, 2024 ONCA 762, leave to appeal to SCC refused, 41596 (1 May 2025).

[11] Stepan Wood, “Mathur v Ontario: Grounds for Optimism about the Recognition of a Constitutional Right to a Stable Climate System in Canada?” (2024) 69:1 McGill LJ 3.

[12] Emmett Macfarlane, “Climate Change, the Charter of Rights, and ‘Positive vs Negative Rights’” (22 October 2024), online (blog): Seven/Fifty

<https://www.sevenfiftyblog.ca/post/climate-change-the-charter-of-rights-and-positive-vs-negative-rights>  [https://perma.cc/L4CF-XNVY].

[13] Martin Olszynski et al, “A Landmark Decision in Canadian Charter-based Climate Litigation: Mathur v Ontario, 2024 ONCA 762” (31 October 2024), online (blog): ABlawg <https://ablawg.ca/2024/10/31/a-landmark-decision-in-canadian-charter-based-climate-litigation-mathur-v-ontario-2024-onca-762/> [https://perma.cc/YG84-UG2H].

[14] Ibid.

[15] Mathur, supra note 6 at para 70.

[16] Carter v Canada (Attorney General), 2015 SCC 5.

[17] Canada (Attorney General) v Bedford, 2013 SCC 72.

[18] Charter, supra note 3, s 1; Centre for Constitutional Studies, “Oakes Test” (4 July 2019), online: <https://www.constitutionalstudies.ca/2019/07/oakes-test/> [https://perma.cc/CND7-SGYD].