The arguments advanced by the provinces will be music to senators' ears, which have been ringing for months with accusations of fraudulent expenses and corruption by four of their own.
Long derided as an unelected, unaccountable retirement home for party hacks, flacks and bagmen, the still-raging expenses scandal has prompted even longtime champions of Senate reform, such as Saskatchewan Premier Brad Wall, to join the campaign to do away with the red chamber entirely.
Against that backdrop, the top court's three-day hearing, which begins Tuesday, will serve as a history lesson, reminding Canadians why the Senate exists and the importance of the role it plays in the country's federation.
The factums filed by the provinces do not address the merits of abolition or Prime Minister Stephen Harper's modest reform proposals, which would impose term limits on senators and create a process for electing them.
But the vast majority make the case that the Senate is too fundamental to the functioning of the federation to allow reform without significant provincial approval, or abolition without their unanimous consent.
The contention that the Senate was an essential part of the "Confederation bargain" — designed to give equal clout to the small Atlantic provinces and Quebec (Lower Canada) in counterbalance to the dominance of Ontario (Upper Canada) in the elected House of Commons — is a repeated refrain in the provincial factums.
"The Senate is an important part of Canada's federal system and was a key element of the Confederation bargain," Ontario argues. "It was designed to play a significant role in reflecting regional interests and protecting minority interests."
"The Senate is a constitutionally entrenched national institution which was born out of the essential compact that gave rise to Confederation," echoes Newfoundland and Labrador.
"This was the bargain struck at Confederation," concurs British Columbia.
Indeed, several provinces argue that Canada itself might not have come into being had the Fathers of Confederation not agreed to the creation of a Senate.
Ontario, New Brunswick and Newfoundland cite one of the founders of Confederation, George Brown: "Our Lower Canada friends have agreed to give us representation by population in the Lower House, on the express condition that they shall have equality in the Upper House. On no other condition could we have advanced a step."
And New Brunswick maintains the Senate remains "an essential component of our federal form of government" to this day.
"The realities of Canadian demographics are such that 'less numerous' provinces such as New Brunswick must maintain an interest in protecting and strengthening their voices in national affairs.
"The protection of sectional and provincial interests, in addition to the protection of minority interests, is of utmost importance and New Brunswick submits the Senate, based on the principles upon which it was created, has an important role to play in this regard."
The provincial factums also note the Fathers of Confederation deliberately eschewed an elected Senate in the belief that senators appointed for life would be more independent, capable of giving sober second thought to legislation but not having the democratic legitimacy to defy the elected House of Commons willy nilly.
As Canada's first prime minister, Sir John A. Macdonald, is quoted as saying in several provincial factums: "It must be an independent House, having a free action of its own, for it is only valuable as being a regulating body, calmly considering legislation initiated by the popular branch and preventing any hasty or ill-considered legislation which may come from that body, but it will never set itself in opposition against the deliberate and understood wishes of the people."
Several provinces note the maritime provinces were insistent on an appointed Senate, modelled on Britain's House of Lords. Ontario further points out that Upper Canada, which had experimented with an elected upper chamber, found the results "unsatisfactory," "due to the difficulty in getting members of high quality to stand for election, the large constituencies and the cost of running."
Ontario cites Britain's colonial secretary, the Earl of Carnarvon, saying no issue was more difficult for the Fathers of Confederation to settle than the composition of the Senate. The purpose, Carnarvon said, of an appointed chamber was twofold: "That it should be strong enough to maintain its own opinion, and to resist the sudden gusts of popular feeling; secondly, that it should not be so strong that it should be impenetrable to public sentiment and, therefore, out of harmony with the other branch of the legislature."
History notwithstanding, critics of the Senate argue that an unelected chamber is an anachronism in this day and age.
But Prince Edward Island notes that first ministers didn't change the composition of the upper house when they agreed to patriate the Constitution in 1982.
"It can not, therefore, be said that the Senate, as now constituted, is somehow inconsistent with our established constitutional norms or the Canadian conception of democracy — modern or otherwise."
The Harper government argues that its reform proposals can be achieved unilaterally, with no provincial input, while abolition would require the approval of at least seven provinces representing 50 per cent of the population — the so-called 7-50 constitutional amending formula.
But few provinces concur.
Only Ontario and Saskatchewan agree that term limits could be imposed unilaterally, provided they are at least nine years in duration. Only Alberta and Saskatchewan agree that Ottawa could unilaterally create a process for electing senators.
All other provinces maintain such reforms would require 7-50 approval.
Only Alberta, Saskatchewan and B.C. agree that abolition would could be achieved with the approval of seven provinces. All the rest say unanimous consent would be required.
The high constitutional standards that most provinces insist must apply go a long way to explaining why past efforts to reform the Senate have failed and why abolition could well be an insurmountable hurdle — no matter how appealing in the midst of scandal.
Manitoba, whose NDP government favours abolition, acknowledges it would be more convenient if reform or abolition could be accomplished more easily.
"Convenience, however, is not a cornerstone of a federal constitutional democracy."
"It is necessary for any interpretation (of the amending procedures) to preserve and protect the essence of the bargains struck in 1867 and 1982," concurs P.E.I.
"There are burdens in a federation such as ours but, at the end of the day, a deal is a deal."
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