After Pope Francis’ historic apology acknowledging the Catholic Church's role in Indigenous residential schools in Canada, which the Assembly of First Nations (AFN) has called "a significant gesture,” many advocates are calling for him to also rescind the Doctrine of Discovery.

Banners reading “Rescind the Doctrine” were seen among protesters during the Pope’s visit to Canada, along with voices in the audience urging a public denouncement.

The Doctrine of Discovery, dating back to the late 14th century, is one of several principles of international law known as jus gentium, or "law of nations," which were applied between European nations in the 14th and 15th centuries.

It was used as a legal and moral justification for European countries conquering land that wasn’t their own and laid the groundwork for laws like Canada's Indian Act and the system of residential schools.

Pope Francis did not directly mention the Doctrine of Discovery when he delivered his apology to residential school survivors in Maskwacis, Alta., which has prompted criticism that it failed to fully recognize the role played by the Catholic Church in the residential school system.

“(The doctrine) wasn't just about an authorization to steal the lands and resources, it was also about subduing the so-called ‘barbarous nations,’” Dr. Pamela Palmater, lawyer and the chair in Indigenous governance at Toronto Metropolitan University, told CTV’s Your Morning on Tuesday.

“So, all of the violence and death that happened to Indigenous peoples on these territories is also a part of that.”

According to Indigenous Corporate Training Incorporated (CTI), a training organization that guides professional relationships between businesses and Indigenous people in North America, there is one major reason the Doctrine of Discovery continues to impact First Nations communities: it has never been officially renounced by the head of the Catholic Church.

"(The doctrine) remains the basis for Canadian law and as such continues to impact Indigenous Peoples," CTI wrote on their website.

Palmater says that the Doctrine of Discovery remains “infused” in Canada’s legal system to a degree that it continues to impact the country’s ideologies, concepts, and even common laws.

“You see the Supreme Court of Canada always just assumes that Canada has sovereignty, even though it is acknowledged that its Indigenous peoples have actual sovereignty, and that's where the reconciliation takes place,” she said.

“I think an official repudiation of it and the concepts that go along with it, both by the Church and the government will help to start to, you know, unravel those cases over time.”

Last year, the Canadian government rejected the doctrine, passing Bill C-15, which aims to harmonize Canada's laws with the United Nations Declaration on the Rights of Indigenous Peoples. The government called the doctrine: “racist, scientifically false, legally invalid, morally condemnable and socially unjust.”

In a January 2018 report on Dismantling the Doctrine of Discovery, the AFN says that it “remains deeply concerned about the contemporary ramifications of the doctrine of discovery and other discriminatory practices.”

Those ramifications include Indigenous communities in Canada still struggling with land disputes with the government.

The Tsilhqot'in Nation, representing six First Nation communities with a common culture and history, is the only Indigenous group to win recognition of its Aboriginal title to a specific area of land through Canada's highest court.

The lawsuit was brought about by the B.C. government's decision in 1983 to provide a commercial logging permit on land that the Tsilhqot'in considered to be a part of their traditional territory. The First Nation raised concerns and demanded a logging ban.

According to the historic decision, Indigenous nations have a right to utilise and benefit from the land, but they do not own it. Instead, they have a beneficial stake in it.

Although Pope Francis's decision to revoke the Doctrine of Discovery would have symbolic value in the path to reconciliation, Palmater claims that it would not rescind its impact on Canadian law without some additional work.

“I think an official repudiation of (the doctrine) and the concepts that go along with it, both by the church and the government will help to start … to reject those concepts that (they) had any legal claim to these territories,” she said.

With files from Mitchell Consky and The Canadian Press