They say they are taking the legal route because Prime Minister Stephen Harper's Conservative government refuses to heed the calls of aboriginal groups, civil-liberty organizations and opposition parties to hold an inquiry.
"I think that there is no other choice than to go to court," said Sen. Serge Joyal, who wrote the legal argument.
"This is a way to press upon the government in a more efficient manner, so the government will have to defend its stance in court and be shamed by public opinion. That, I think, might compel the government to act, finally."
Joyal, a lawyer by training, cites sections of the Charter of Rights and Freedoms, other legal cases and the United Nations Declaration on the Rights of Indigenous Peoples to buttress his argument for an inquiry.
He and his Senate colleague Lillian Dyck are in the early stages of finding someone who will take the case to Federal Court.
"The first party to launch an action is normally a person who is directly aggrieved or a person who has a direct interest," Joyal said.
Such a case could be before the courts for years.
But Joyal and Dyck say a court case would put pressure on the Conservative government to call an inquiry, something it has so far refused to do.
"It could be an aspect of shaming," Dyck said.
"It could also be alerting Canadians to the fact that there is a underlying right amongst aboriginal women to be protected. And therefore, it might also then somehow increase pressure in other ways.
"It may not be through a formal organization, but you know, there is an election coming up, and pressure could be put on their local members of Parliament."
The Conservatives have resisted calls for an inquiry, saying dozens of studies have already been done and now is the time for action.
The government's latest budget included a five-year, $25-million renewal of money aimed at stopping violence against aboriginal women and girls.
Kellie Leitch, the minister for the status of women, recently elaborated on how the money will be spent.
Over the next five years:
— $8.6 million will be spent to develop community safety plans;
— $2.5 million will be spent on projects to raise awareness of the cycles of violence and abuse;
— $5 million will be spent on projects to encourage boys and men to denounce and prevent violence against aboriginal women and girls;
— $7.5 million will be spent on victim services and help for victims and families;
— $1.4 million will be spent on sharing information and resources with communities and organizations and to report on progress and results.
The government is also spending additional money on shelters and activities to prevent family violence, a DNA-based missing persons database and continuing support for police investigations through the National Centre for Missing Persons and Unidentified Remains and special RCMP project teams.
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