The decision comes one day after the Truth and Reconciliation Commission released a momentous report on the same school system.
Federal Court in Vancouver certified a class-action lawsuit on Wednesday proposed by the former aboriginal students known as "day scholars," who attended the notorious schools but returned to their homes at night.
"When we phoned home and told them the news, I mean, our plaintiffs were crying," said Jo-Anne Gottfriedson, with the Tk'emlups te Secwepemc Indian band in the British Columbia Interior.
"Our journey is long, but we're prepared and I know that Canada, if they're really sincere about reconciliation, then they will meet us in a good way."
The certification followed the work of the commission, which over six years of hearings documented the traumatizing misconduct inside Canada's residential schools. The report branded the survivors' collective ordeal "cultural genocide" and made 94 recommendations.
Though the commission was a result of the largest class-action settlement in Canadian history, some aboriginals said they've still never received redress.
"The day scholars have for too long been left out of the discussions," said Chief Calvin Craigan of the Sechelt Indian Band in a news release.
"Through this decision we have a strong signal from the court that day scholars count."
The new legal action was launched by two B.C. aboriginal bands, from which at least 300 survivors have so far been identified. More claimants are believed to reside across Canada.
They're also seeking compensation for the children of survivors and their member bands.
They want a declaration the government also failed to protect aboriginal language and culture for daytime-only students.
The federal government can appeal.
A spokeswoman for Aboriginal Affairs and Northern Development Minister Bernard Valcourt said in an email that officials will review the courts decision and determine next steps.
Chief Shane Gottfriedson, of the Tk'emlups te Secwepemc band, said many band members bravely volunteered as representatives in the suit.
"While the decision ... is just one step towards finally receiving justice, it is a very important one," he said in the release.
Grand Chief Stewart Phillip of the Union of B.C. Indian Chiefs said testimony during the commission showed many abuses occurred during the day, and he's elated by the court's ruling.
"I think it will be equally effective in assisting the day scholar survivors to reach a point of closure in their equally traumatic experiences," he said.
Preparations are now underway for the two First Nations' bands to notify class members. They expect the outcome of any trial to be months or years away.
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(The Canadian Press, CFJC)