The rulebook for a future Quebec referendum – specifically, the minimum margin by which the “Yes” side would have to win before the federal government negotiated secession – was a flashpoint in last week’s leaders’ debate. In this post, I review the Supreme Court of Canada’s 1998 decision in the Secession Reference and examine the leaders’ rhetoric and their respective parties’ positions through the lens of constitutional law.

Thomas Mulcair: Mr. Trudeau has an obligation, if he wants to talk about this subject, to come clean with Canadians. What’s his number? What is your number, Mr. Trudeau? Justin Trudeau: First of all, Mr. Mulcair — Mulcair: You’re not answering. Trudeau: — I don’t question your patriotism. Mulcair: You haven’t answered. Trudeau: The question is — Mulcair: What’s the number, Justin? Trudeau: — why is your policy so reckless? You want a number, Mr. Mulcair? Mulcair: Yeah, give us a number. Trudeau: I’ll give you a number. Nine. My number is nine. Nine Supreme Court justices said one vote is not enough to break up this country, and yet that is Mr. Mulcair’s position. He wants to be Prime Minister of this country, and he’s choosing to side with the separatist movement in Quebec and not with the Supreme Court of Canada…. Paul Wells: — one more chance, Mr. Trudeau, to name a margin above 50 percent that you think would be acceptable. Trudeau: The Supreme Court said very clearly that Mr. Mulcair’s number is not the right one.

For law nerds, last Thursday’s leaders’ debate was a treat. Not since Paul Martin’s 2006 promise to delete the Notwithstanding Clause has the Constitution provided comparable fodder for debate-night fireworks.

Yet, there it was: The Supreme Court of Canada’s unanimous judgment in Reference re Secession of Quebec, [1998] 2 S.C.R. 217 (the “Secession Reference”) – and in one of the evening’s more notable zingers, no less.

The above-quoted exchange came after Justin Trudeau criticized Thomas Mulcair for his party’s promise to repeal the “Clarity Act” – or, to its friends, An Act to give effect to the requirement for clarity as set out in the opinion of the Supreme Court of Canada in the Quebec Secession Reference, S.C. 2000, c. 26. The Clarity Act provides that “[t]he Government of Canada shall not enter into negotiations on the terms on which a province might cease to be part of Canada” if “the House of Commons determines … that a referendum question is not clear” and “unless the House of Commons determines … that there has been a clear expression of a will by a clear majority of the population of that province” to secede: ss. 1(6) and 2(4). The NDP would replace the Clarity Act with a promise to negotiate secession after a simple separatist majority (“50% plus one”) in a referendum.

Mr. Trudeau’s claim that “[n]ine Supreme Court justices said one vote is not enough to break up this country, and yet that is Mr. Mulcair’s position,” isn’t wrong; the NDP’s policy would indeed open the door to secession in the event of the slimmest possible “Yes” victory. It would also invite constitutional chaos by allowing other provinces to boycott the resulting negotiations, or even to veto separation entirely.

But Mr. Trudeau’s assertion isn’t entirely accurate, either.

Could one vote be enough to break up the country?

Yes, it could be. “[N]ine Supreme Court justices” didn’t actually say otherwise. The Secession Reference’s “clear majority” threshold is a floor, not a ceiling; it’s the point at which the federal government and the other provinces must come to the table to negotiate, not the point at which they may.

Mr. Trudeau is technically right that one vote – or any number of votes – in a referendum wouldn’t be enough, on its own, to break up the country; you’d need a constitutional amendment to do that: see Secession Reference, at paras. 84 and 97. Nor would one vote be sufficient to require the federal government and the other provinces to negotiate such a constitutional amendment. That’s because, as the Supreme Court held in the Secession Reference, Canada’s Constitution “requir[es] broad support in the form of an ‘enhanced majority’ to achieve constitutional change”: at para. 77. Though “[t]he democratic principle … would demand that considerable weight be given to a clear expression by the people of Quebec of their will to secede from Canada,” just how “clear” such an “expression” must be cannot not be stated quantitatively. Rather, in the court’s words, at paras. 87 and 100:

We refer to a “clear” majority as a qualitative evaluation. The referendum result, if it is to be taken as an expression of the democratic will, must be free of ambiguity both in terms of the question asked and in terms of the support it achieves….

“[A] clear majority on a clear question” would constitute “[t]he clear repudiation by the people of Quebec of the existing constitutional order”: Secession Reference, at paras. 88 and 100. This, the court determined, “would confer legitimacy on demands for secession, and place an obligation on the other provinces and the federal government to … enter[] into negotiations”: Secession Reference, at para. 88.

The corollary of the court’s ruling is that, unless “a clear majority” of “the people of Quebec” vote for sovereignty “on a clear question”, neither the federal nor any provincial government is obligated to negotiate Quebec’s secession. Whether or not a referendum majority is “clear” is a qualitative question, not a quantitative one, and constitutional change – such as the secession of a province – requires an “enhanced majority”. Put simply: “50% plus one” isn’t enough.

That sounds a lot like Mr. Trudeau’s criticism of Mr. Mulcair: “[O]ne vote is not enough … and yet that is Mr. Mulcair’s position.” But “not enough” to do what? Last Thursday, Mr. Trudeau said, “not enough to break up the country.” Not quite. What “[n]ine Supreme Court justices” actually said was that one vote isn’t enough to “place an obligation on the other provinces and the federal government” to negotiate secession.

In declaring that Mr. Mulcair “wants to be Prime Minister of this country, and he’s choosing to side with the separatist movement in Quebec and not with the Supreme Court of Canada,” Mr. Trudeau was two-thirds correct. Yes, his opponent wants to be Prime Minister, and, yes, his policy on a future referendum is essentially the same as that of the Bloc Québécois. But that policy isn’t necessarily offside the Supreme Court’s ruling in the Secession Reference. Unlike the Clarity Act, nothing in the court’s decision would prevent the federal government from negotiating with Quebec after a 50%-plus-one “Yes” victory. In such circumstances, Ottawa would not be obliged to come to the table – not that it couldn’t choose to do so. As the court said, at paras. 87-88:

[T]he Constitution does not itself address the use of a referendum procedure, and the results of a referendum have no direct role or legal effect in our constitutional scheme…. [A] referendum, in itself and without more, has no direct legal effect…. In Canada, the initiative for constitutional amendment is the responsibility of democratically elected representatives of the participants in Confederation. Those representatives may, of course, take their cue from a referendum, but in legal terms, constitution-making in Canada, as in many countries, is undertaken by the democratically elected representatives of the people.

The federal government and the provinces may constitutionally negotiate the country’s dissolution without any referendum vote at all. It follows that they may also do so on the basis of a referendum majority that is less than “clear”. But, without “[t]he clear repudiation by the people of Quebec of the existing constitutional order”, neither the federal government nor the provinces would have “an obligation … to acknowledge and respect that expression of democratic will by entering into negotiations”: at para. 88. This is where Mr. Mulcair’s position, though not inconsistent with the Secession Reference, opens the door to legal and political mayhem.

Can one Thomas Mulcair be enough to amend the Constitution?

You’ll find a neat summary of the foregoing in the Clarity Act’s preamble:

[T]he Supreme Court of Canada has determined that the result of a referendum on the secession of a province from Canada must be free of ambiguity both in terms of the question asked and in terms of the support it achieves if that result is to be taken as an expression of the democratic will that would give rise to an obligation to enter into negotiations that might lead to secession.

The Clarity Act then provides that, unless this threshold is met – that is, unless the obligation to negotiate arises – the Government of Canada may not participate in secession negotiations. One virtue of this approach, say the Clarity Act’s supporters, is that it makes it more difficult to break up the country; unless sovereigntists win a clear majority on a clear question in a referendum, Ottawa won’t even begin to negotiate the constitutional amendment necessary to effect the separation of a province from Canada.

The Clarity Act’s federalist detractors respond that, by entertaining a scenario in which Quebec stays in Canada after most (but not enough) Quebecers vote “Yes”, the law perversely makes a “Yes” majority more likely. As Mr. Mulcair said last Thursday: “If yes doesn’t mean yes, then people could decide to vote yes as a way of sending a signal. That’s why it’s a dangerous political game”.

Mr. Mulcair’s position may be plausible in terms of political strategy, but it is less so as a matter of constitutional law. It ignores the subtler form of clarity that the Clarity Act achieves – namely, the certainty that the federal government will only take part in negotiations in circumstances in which the provinces are similarly obligated to participate.

Recall that, in the Supreme Court’s words, “[t]he secession of a province from Canada must be considered, in legal terms, to require an amendment to the Constitution, which perforce requires negotiation”: Secession Reference, at para. 84. But negotiation would be the beginning, not the end, of the process of amending the Constitution. The House of Commons, the Senate, and at least some of provinces would need to sign on before any amendment became law.

It isn’t clear how many provinces would be required to approve an amendment removing Quebec (or any other province) from Canada. Some commentators argue for the unanimity procedure, under s. 41 of the Constitution Act, 1982, by which every provincial legislature would need to agree to a proposed amendment. Others prefer the “seven-fifty” formula, under s. 38, by which the assent of at least two-thirds (i.e., seven) of the provinces representing at least 50% of the population would be required. In either case, a minority of the other provinces would have an effective veto over a province’s departure. In the Secession Reference, at paras. 96-97, the Supreme Court recognized this possibility, while alluding ominously to what might happen if it ever transpired:

No one can predict the course that such negotiations might take. The possibility that they might not lead to an agreement amongst the parties must be recognized…. While the negotiators would have to contemplate the possibility of secession, there would be no absolute legal entitlement to it and no assumption that an agreement reconciling all relevant rights and obligations would actually be reached. It is foreseeable that … negotiations … could reach an impasse. We need not speculate here as to what would then transpire. Under the Constitution, secession requires that an amendment be negotiated.

The practical difficulty of the NDP’s promise to repeal the Clarity Act is that it makes such an impasse more likely. As Prime Minister of Canada, Thomas Mulcair would choose to begin secession negotiations with the Government of Quebec after the “Yes” side won a referendum by a single vote, but – and here’s the rub – none of the provinces would be obligated to join him. The Clarity Act keeps the Government of Canada away from the table until every necessary participant is obliged to join. The NDP position raises the spectre of an optional negotiation in which the provinces (whose approval would ultimately be necessary) would be able to boycott the process in the first place.

So, Mr. Mulcair is being disingenuous when he compares his party’s position to that of the British government ahead of last year’s referendum on Scottish independence. (“Our position is the exact same as the one taken by the mother of all parliaments in the recent Scottish referendum,” he said last month.) The U.K. isn’t a federation. Canada is. Britain’s Parliament could constitutionally agree to Scottish independence on its own. Canada’s couldn’t.

A 50%-plus-one victory for the “Yes” forces in a referendum would be a political disaster, with or without the Clarity Act on the books. Yet, without it, different federal and provincial reactions to a “Yes” vote would turn that political disaster into a constitutional nightmare. That’s what the NDP is promising.

Does it matter?

These post-referendum scenarios are hypothetical, but the dispute between the Liberals and the NDP over the ground rules for a future referendum isn’t. Liberals see the issue as one that could alienate the NDP’s soft-nationalist supporters in Quebec from their partisan bedfellows in the rest of Canada, which is why Trudeau will continue to needle Mulcair on the subject until Election Day. Thereafter, it could prove a sticking point in post-election coalition or accord negotiations between the two parties; Trudeau has referred to the NDP’s position as “yet another example of where co-operation between the Liberals and the NDP in the coming years is out of the question.”

It bears repeating, however, that it was the NDP, not the Liberals, who turned the Clarity Act into an election issue. In adopting the Bloc’s position, the NDP hoped to make inroads with Quebec voters who might otherwise vote for sovereigntist parties. In 2011, that strategy paid off. It also dragged the Supreme Court’s 1998 decision in the Secession Reference back into federal politics, and, last Thursday, into Mr. Mulcair’s face. Given the constitutional ramifications of his party’s position – and the politically-inconvenient truth that, as Prime Minister, Mr. Mulcair would negotiate the breakup of Canada when he was under no legal obligation to do so – that’s precisely where it should be.