"Theoretically it's billions and billions of dollars," Robert Lovelace, a global development studies professor at Queen's University in Kingston, Ont., and retired Ardoch Algonquin First Nations chief, told CBC News.
Following Tuesday's ruling, the financial obligations of the government are still unclear. The court said it was not prepared to "make some general statement concerning the federal government's fiduciary duty."
Meanwhile, the government could appeal the ruling to the Supreme Court, meaning it could be years before any benefits are seen by Métis or non-status Indians.
"One of the arguments the Crown made in the case was that it's just going to provide a lot more litigation," Lovelace said.
But what the ruling could mean is that Métis and non-status Indians may be entitled to the same benefits as registered status Indians. Those benefits include some tax exemptions if living on a reserve, hunting and fishing rights, health benefits and some education subsidies.
"The federal government fought this ... with a vehemence because the stakes are really really high," said David McNab, a professor at Toronto's York University and Métis historian who has worked for almost 40 years on aboriginal land and treaty rights issues.
"The cost — that's the primary motivation for the federal and provincial government. They don't want to be hung up with the responsibility of costs that have been built up," McNab said.
For example, Lovelace said registered status Indians who work on reserves do not have to pay income tax on income earned on the reserve.
But for non-status people who don't have a reserve yet live within a traditional territory, it could be argued that they will no longer have to pay income tax, he said.
What could be more of a financial concern for the government are cases in which non-status Indians had paid sales tax in the past, now claim they should have been exempt from those taxes and be reimbursed, Lovelace said.
The government may also have a difficult case to make that it doesn't have the money to pay out all the benefits and claims.
"The courts have tended to accept a little bit of that argument but they're also forced to recognize what's legal," Lovelace said.
The ruling also means the government can no longer play the "divide and conquer" game between status Indians and non-status Indians and Métis, Lovelace said, adding that it could lead to a reconciliation among the groups since they are now all on equal ground.
However, he did acknowledge that there could be some tension as more groups will be sharing the government pie.
"There's always been concern that there's not enough money to go around, so if you add people to the pot, the meal's going to get thinner. I hope that that can be overcome," Lovelace said.
The decision could also prompt a spike in Métis membership applications. Randy Ranville, a genealogist with the Métis Culture and Heritage Resource Centre in Winnipeg, told The Canadian Press the centre will likely be swamped following the court decision.
According to the 2006 census, nearly 400,000 Canadians self-identified as Métis, although only about half are officially recognized. Each province has a Métis organization which registers members and outlines its own requirements for status.
Typically, proof lies in an official family tree, accompanied by birth certificates and other documentation with ties to the historic Métis homeland.
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