The federal government has asked the high court for guidance on what it would take to reform the upper chamber — and whether it can abolish the body without provincial consultation.
The provinces and territories had until Friday afternoon to submit their views on the Senate questions.
So far, everyone seems to agree that Ottawa cannot act alone to overhaul or outright abolish the upper chamber. Where they differ is in the details.
Saskatchewan and Alberta agreed with the federal government position that all that is needed for abolition is the so-called 7/50 rule — the consent of seven provinces, representing at least half of the population.
"Alberta continues to lead Senate reform efforts and our province's position is that fundamental changes to the federal system requires input from the partners of Confederation," Premier Alison Redford said in a statement.
"But no one province should hold a veto to block important and necessary Senate reform."
Adds Saskatchewan: "Unanimity is not required for any of the proposals identified in the constitutional questions."
Ontario, Quebec, Newfoundland and Labrador, Manitoba, Nunavut, Prince Edward Island, Nova Scotia and New Brunswick counter that the unanimous consent of the provinces is indeed needed to get rid of the Senate.
The Northwest Territories says unanimous consent isn't enough and its residents must be consulted before any changes are made.
British Columbia got an extension and now has another week to file its opinion. Yukon is not weighing in.
On the questions of whether Parliament alone can set term limits or hold elections for senators, opinions vary.
Alberta argues that while the federal government would have to consult the provinces before setting Senate term limits, it could conceivably change the rules so senators would have to be elected instead of appointed, as they are now.
Alberta is the only province to elect nominees for Senate appointments.
Ontario says Parliament does not need the provinces' consent to set term limits of nine years or longer. However, the province says the 7/50 rule would apply if Parliament wants to set Senate term limits of less than nine years.
Ontario also says the 7/50 rule comes into play if Parliament wants to change the rules so that senators must be elected.
The rest of the provinces and territories generally agree that Ottawa cannot act alone on Senate elections or term limits.
Nova Scotia, Manitoba and Saskatchewan say the Senate ought to be abolished.
"It is (Saskatchewan Premier Brad Wall's) position — and the position of his government — that as an institution the Senate is beyond repair and the only reasonable option is to abolish it outright," Saskatchewan's factum says.
Manitoba's attorney general also says the upper chamber is basically flawed and should be abolished.
The Supreme Court also heard from a pair of senators.
Liberal Sen. Serge Joyal says Parliament alone lacks the power to set term limits for senators, hold elections for Senate seats and outright abolish the upper chamber.
Joyal says the Senate could be abolished — but only with unanimous provincial consent. He also says the interests of aboriginals must be taken into account in the process.
Independent Sen. Anne Cools argues Parliament alone does not have the power to set term limits or hold Senate elections, and that unanimous consent is needed for abolition.
In its own submission, the federal government argues "it is constitutionally permissible for Parliament to impose term limits, provide for public consultative processes on Senate appointments, and remove the archaic requirement" that a senator own at least $4,000 worth of land.
Most provinces either abstained or had no opinion on the property question. Only Quebec says it must be consulted before changes are made.
The federal Conservatives say they plan to go ahead with Senate reform — or even outright abolition — once the Supreme Court provides guidance over how they may do so.
The Tories should have the support of the New Democrats if they go the abolition route. The NDP has long wanted to get rid of the Senate.
The Supreme Court is scheduled to hold hearings on the matter in November. It could be months before it delivers its opinion.
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