The B.C. government was the last to submit its factum to the Supreme Court of Canada in a reference case proposed last winter by the Harper Conservatives.
Like other provincial and territorial governments, B.C. says any significant reforms — such as term limits for senators or Senate elections — must follow the amending formula laid out in the 1982 Constitution Act.
That means the approval of seven provinces representing at least 50 per cent of the population.
But a release late Friday from the B.C. Justice minister's office added another caveat: "In British Columbia, a referendum is required by law before the Legislative Assembly can consider constitutional amendments that need the province's approval."
All arguments from interested parties were supposed to be submitted to the court by the end of August, but B.C. was granted a one-week extension.
After years of promising piecemeal reforms without delivering, the Conservative government of Stephen Harper asked the Supreme Court for guidance last February on what it would take to overhaul the Senate — or to abolish it outright.
Most of the provinces and territories have agreed on the 7/50 amending formula — while a number say that abolishing the Senate altogether would require unanimous provincial consent.
B.C. says the Senate can be abolished using the existing 7/50 formula, but rejects the federal government's argument that lesser reforms such as term limits can be enacted by Parliament alone.
"It is clear that provincial involvement is contemplated for all significant changes to the Senate," said the B.C. court factum.
And it makes the case that proposed reforms that "alter how and when a person becomes a senator ... will impact the Senate's ability to function as a thoroughly independent body; they are far from 'housekeeping' matters or ones solely of interest to the federal government..."
The Conservatives first introduced Senate reform proposals soon after coming to power in 2006, but were thwarted in part by a Liberal-dominated upper chamber that demanded the government get a Supreme Court opinion on their constitutionality.
Even after achieving majorities in both the Senate and the House of Commons, however, the Conservatives failed to push forward with promised term limits and Senate elections.
Harper's belated Supreme Court reference came as a Senate expense scandal involving three Harper appointees and one Liberal appointee began to gain public traction last winter.
The court could take up to two years to deliver its response.
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