Indigenous Nations have won a major legal victory in the Canadian province of British Columbia.

On Friday, the Gitxaala and Ehattesaht Nations secured a landmark victory at the BC Court of Appeal, with the support of the First Nations Leadership Council and the BC Civil Liberties Association.

The First Nations Leadership Council (FNLC) and the BC Civil Liberties Association (BCCLA) congratulated the nations on their victory, and said in a joint statement the Court's decision "breathes new life" into Canada's Declaration on the Rights of Indigenous Peoples Act and "affirms the substantive legal effect" of the United Nations Declaration on the Rights of Indigenous Peoples.

The Court's ruling places the British Columbia provincial government's de-prioritisation of UN Declaration implementation "into serious question, specifically not following its own Interim Approach for the development and passing of several key pieces of streamlining legislation, notably the Renewable Energy Projects (Streamlined Permitting) Act and the Infrastructure Projects Act", the FNLC and BCCLA noted.

Friday's ruling by the BC Court of Appeal reversed a lower court's "unduly narrow approach to the legal effect of the Declaration Act" and held that the Declaration Act "incorporates the UN Declaration into British Columbia's positive law".

Union of British Columbia Indian Chiefs president, Grand Chief Stewart Phillip, said Indigenous leaders have, "from the beginning" emphasised that "the provincial government's position on the legal effect of the Declaration Act was inconsistent with the substantial collaborative and cooperative effort that went into developing it".

"The BCCA's decision, and its observation that the provincial government's 'intransigence... does not contribute to the cooperative consultative dynamic to which all concerned should aspire', confirms what we have long understood: that reconciliation requires honourable conduct, good faith, and respect for commitments made. It's time for us to get on with the important work of reconciliation, together," the Grand Chief said.

The Court confirmed that the government of British Columbia must consult and cooperate with First Nations to address inconsistencies between the UN Declaration and the laws of the province, and that the question of whether a law of BC is consistent with the UN Declaration is justiciable (can be tested in a court of law).

The FNLC and BBLA said provincial government "cannot continue its ad hoc and discretionary approach to creating new law that is inconsistent with the UN Declaration".

BC Assembly of First Nations Regional Chief Terry Teegee said "this legal victory sends a ground-shaking message to the provincial government: the Declaration Act is legally binding and cannot be implemented or interpreted in a unilateral Crown approach".

"The Declaration Act is justiciable and First Nations in BC may enforce the legal requirement of consistency with the UN Declaration. The provincial government must honour in good faith the legal commitment it made to the First Nations of this Province," he said.

First Nations Summit Political Executive member Robert Phillips said Indigenous leaders and communities "celebrate and hold up the Gitxaala and Ehattesaht Nations for the significant time and resources they invested into advancing this litigation and holding the provincial government accountable".

"The clear outcome of their persistence and dedication to the protection of their rights is a win for all First Nations in British Columbia," he said.

Veronica Martisius, BCCLA Litigation Staff Counsel, said the decision affirmed "the legal effect of the UN Declaration in BC Indigenous rights must be honoured and respected".

"The work of truth and reconciliation is now and belongs to us all, including the judiciary. There is no reason why the Declaration Act should not be legally enforceable when the government is shirking its duty to align the laws of BC with the rights and standards set out in the UN Declaration," she said.