Appeal decision upholds governments’ fiduciary duty to First Nations

By Saul Joseph, Melanee Bryniawsky and Maria Starko ·

Law360 Canada (March 28, 2024, 11:41 AM EDT) --
Saul Joseph
Saul Joseph
Melanee Bryniawsky
Melanee Bryniawsky
Maria Starko
Maria Starko
In a recent B.C. Court of Appeal decision, Thomas v. Rio Tinto Alcan Inc., 2024 BCCA 62, the court declared that the provincial and federal governments have an ongoing fiduciary duty to protect the Stellat’en and Saik’uz First Nations Aboriginal rights. The court upheld most parts of the lower court’s decision, although the declaratory relief granted to the appellant First Nations was notably expanded.


This case is an appeal from a decision in Thomas v. Rio Tinto Alcan Inc., [2022] BCSC 15 of the B.C. Supreme Court released on Jan. 7, 2022, which held that industry could be liable in nuisance for breaches of Aboriginal title and rights, and interests in reserve lands. In that instance, the court found that statutory authority is a full defence to the nuisance claim. However, the First Nations successfully proved their Aboriginal right to fish for sustenance and social and ceremonial purposes in the Nechako River watershed. The trial judge issued a declaration that each government is subject to an obligation to protect these rights.

The dispute centers around the construction of the Kenney Dam and its impact on two neighbouring First Nations, the Stellat’en First Nation and the Saik’uz First Nation (the First Nations). Seeking both interim and permanent injunctions, the First Nations aimed to restrain Rio Tinto (the company responsible for building the dam) from perpetuating acts of nuisance. Additionally, they sought a mandatory injunction compelling Rio Tinto to release water into the Nechako watershed and restore the river’s flow regime to its original state. The First Nations sought damages in the alternative.

The full facts of the case and details about the decision can be found in our article here.

Court of Appeal: Widening the scope of declaratory relief

While the BCCA upheld the claim in nuisance and the defence of statutory authority, it diverged on the scope of declaratory relief. The trial judge’s declaration was deemed too restrictive. The First Nations had established their Aboriginal right and the water diversion was affecting that right. Consequently, dismissing the nuisance claim did not preclude the possibility of impairment to their right. At trial, the First Nations had established that both levels of government are involved in the regulation of the Nechako River and that regulation adversely impacts their Aboriginal right.

The BCCA agreed that the existence of an Aboriginal right to fish in the Nechako River imposes a positive duty on both B.C. and Canada to safeguard that right, a duty appropriately characterized as a fiduciary obligation (para 422). The governments owe the First Nations a duty to consult regarding annual water management and the flow regulation in the river, whenever contemplating actions that could adversely impact their Aboriginal rights. This engages and stems from the principles of the honour of the Crown. The fiduciary duty of the federal and provincial government owed to the First Nations necessitates that they consider the best interests of the First Nations when making any decisions that may impact the First Nations’ Aboriginal rights (para 429). Importantly, the court made a clear distinction between acting in the First Nations’ best interest and acting in their sole interest.

The B.C. Court of Appeal exercised caution by avoiding too much specificity in the declaration, mindful of indirectly granting relief against Rio Tinto, which the court had denied. However, upon review, the court found the initial declaration too narrow, rendering it practically ineffective for the appellants.

The court amended the declaration. It now explicitly states that B.C. and Canada’s fiduciary duties owed to the First Nations encompass safeguarding the First Nations right to fish within the governments’ annual water allocation and flow regimes. Additionally, the declaration recognizes the Crown’s duty to consult with the First Nations when water management poses the potential for novel adverse impacts on their established rights.


In a recent press release, the Stellat’en and Saik’uz First Nations welcomed this development as a “very significant step forward” in their prolonged battle against the Nechako River’s degradation and infringement upon their Aboriginal rights. On a broader level, this decision establishes a strong precedent for other First Nations whose rights face adverse impacts from water regulation. It also paves the way for the formulation of a comprehensive consultation framework concerning water regulation.

Moreover, Thomas v. Rio Tinto Alcan Inc. contributes to the growing body of legal precedents concerning the Crown’s ongoing duty to consider cumulative impacts on Indigenous rights. Building upon the principles outlined in Yahey v. British Columbia, 2021 BCSC 1287, we continue to see a shift in jurisprudence toward recognizing the Crown’s ongoing obligation to consider Indigenous rights within the broader context of resource management regimes.

Saul Joseph is a partner at Clark Wilson, one of Western Canada’s largest law firms, where he chairs the Indigenous law practice. He works closely with Indigenous communities, businesses and government on economic development initiatives, including Aboriginal business ventures and transactions, First Nations land development, consultations and accommodations, Impact Benefit Agreements, Aboriginal and Treaty Rights and First Nations governance. Melanee Bryniawsky is an associate at Clark Wilson whose practice covers Indigenous law, general business law and charities and not-for-profits. Maria Starko is an articling student at Clark Wilson.

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