Climacteric Litigation Decisions – Part V: Ontario’s Court of Appeal Delivers Judgment on Climate Action

This article is a continuation of a series of articles on climate change litigation titled Climacteric Litigation Decisions.

In previous articles, we discussed the American decision in Held, et al v State of Montana, et al,[1] (“Held”). In Held, the Montana First Judicial District Court, located in Lewis and Clark County, Montana, USA, handed down an Order that is reportedly the first major climate litigation decision to come from a North American court. In the Order, claims based on environmental rights were upheld. This decision has been appealed to Montana’s Supreme Court, and a ruling is pending.

In the same article series, we summarized the history of climate change litigation in Canada and the USA, the potential impact of Held, and the likelihood of further climate change litigation. (Each article in the series can be found here: Part I, Part II, Part III, and Part IV).

In Part II, we commented on significant climate actions currently underway in Canada, including Mathur, et al v Her Majesty the Queen in Right of Ontario,[2] (“Mathur”) and La Rose v Her Majesty the Queen[3] (“La Rose”). At the time, both Mathur and La Rose were awaiting decisions in appellate courts. In Part IV, we summarized the Federal Court of Appeal’s concurrent judgment on two decisions considered on appeal - La Rose and Misdzi Yikh v Canada,[4] (“Misdzi”) – which authorized novel climate change actions against Canada to move forward.

On October 17, 2024, the Ontario Court of Appeal (“Court of Appeal”) released its decision in the Mathur action, which is summarized below.

Background

Mathur is a significant legal battle regarding climate change and constitutional rights, which addresses the province's responsibilities under its climate legislation and how these obligations intersect with the rights of individuals.

In 2018, the Government of Ontario passed the Cap and Trade Cancellation Act (the “Act”),[5] which replaced prior greenhouse gas reduction targets for 2020, 2030, and 2050 with a lower target for 2030. In response, seven youths brought an action against the Government of Ontario alleging that the government had violated the Canadian Charter of Rights and Freedoms ("the Charter")[6] by failing to address climate change.[7] In 2020, the defendants filed a motion to dismiss, arguing that the Charter does not guarantee a right to a stable climate and that the plaintiffs had shown no reasonable cause of action. This motion was dismissed by the Ontario Superior Court of Justice on the basis that it was not plain and obvious that there was no cause of action, and permitted a full hearing which took place in front of the Court of Appeal in January 2024. The decision of the Court of Appeal was released on October 17, 2024.[8]

Key Legal Findings: Ontario's Statutory Obligations vs. Positive Rights

As noted, at the heart of this action is the Act, which repealed previous greenhouse gas (“GHG”) reduction targets and required the Ontario government to establish new ones. In doing so, Ontario set a target of reducing emissions by 30% below 2005 levels by the year 2030. The appellants contended that this target was insufficient to protect them from the severe impacts of climate change, given the overwhelming scientific consensus that more stringent action is necessary.

The appellants' case rested on two essential rights under the Charter:

• Section 7: The right to life, liberty, and security of the person; and
• Section 15: The right to equality, including protection against discrimination.

The appellants argued that Ontario's insufficient GHG reduction target endangered their right to life, liberty, and security of the person (section 7) by exposing them to the harmful and disproportionate effects of climate change, including increased mortality and severe health risks. Furthermore, they claimed these impacts are unevenly distributed across the population, disproportionately affecting youth and Indigenous communities, thus violating their right to equality (section 15).

The Court of Appeal’s Rationale: A Mischaracterization of the Claims

The Court of Appeal found that the application judge in the lower court erred in her analysis under sections 7 and 15 of the Charter, stating that the application judge had incorrectly framed the appellants' claims as seeking to impose positive obligations on the government to combat climate change. Instead, Ontario had voluntarily assumed statutory obligations under the Act.

The question was not whether Ontario had a general duty to act, but whether its specific climate targets complied with its statutory obligations and respected the appellants' Charter rights. The Court of Appeal found that by framing the case as an attempt to impose positive obligations on the government, the application judge failed to properly assess whether Ontario’s emission reduction targets, as mandated by statute, complied with its constitutional obligations.

The Court of Appeal further noted that Ontario had already assumed the responsibility to set GHG targets under the Act, making the issue one of statutory compliance rather than a freestanding obligation to act.

 Of note, the Court of Appeal found the application judge correctly acknowledged the appellants were experiencing an increased risk due to climate change, quoting from the application judge:

... it is indisputable that, as a result of climate change, the [appellants] and Ontarians in general are experiencing an increased risk of death and an increased risk to the security of the person.[9]

However, the Court of Appeal found the application judge’s conclusion that the appellants had not established sufficient causation for their Charter claims was difficult to reconcile with the evidence. Specifically, the Court of Appeal highlighted the unchallenged expert evidence presented in the action which demonstrated the devastating consequences of climate change, such as more frequent and severe weather events, as well as the greater harm inflicted on vulnerable populations, including Indigenous peoples. Therefore, the application judge’s findings were contradictory. The Court of Appeal further emphasized that the application judge's erroneous framing of the action had likely influenced her analysis of the Charter claims.

Procedural Outcome and Implications

The Court of Appeal set aside the lower court’s dismissal of the application and remitted the matter for reconsideration. This means that the appellants’ claims will now be reevaluated by the lower court, but under the correct legal framework - one that focuses on whether Ontario’s execution of its statutory climate obligations is constitutionally compliant.

This ruling is particularly important for the appellants, who are young Ontarians, some of whom are Indigenous. The decision gives the appellants another opportunity to challenge Ontario’s climate policies, this time with a clearer focus on Ontario’s statutory obligations and its duty to comply with their Charter rights.

Conclusion

Ontario's climate targets are now under renewed scrutiny, and the province will have to defend its policies in light of its statutory climate obligations and the rights enshrined in the Charter.

This case will set a precedent for future climate change litigation in Canada, as it highlights that governmental climate policy is not immune from constitutional scrutiny, particularly when the rights of vulnerable groups are at stake. The Ontario Court of Appeal has made it clear that climate change is not just an environmental issue, it is a human rights issue as well.

Stay tuned for updates on this action, as well as future climate change decisions, including the La Rose and Misdzi actions.

For more information on environmental and climate change litigation, contact Stuart Chambers, Joelle French, Aaron Mann, or any member of our Environmental & Energy Practice Group.