In Canada, how was it legal to pass the Constitution Act 1982 to require certain amendents by unanimity if not all provinces agreed to it?

Question

In British legal doctrine, a majority vote in Parliament has no right to bind the future parliament and what it might do, and follows an obvious principle. If a prime minister enacted a bill that said it could only be repealed by say 2/3 of the MPs but that many MPs didn't vote for the bill, how is that even remotely constitutional?

In Canada, how can you enact a law like the Constitution Act of 1982 where it had a clause stating that certain kinds of amendments require unanimity among all eleven elected sovereign legislatures given that when it was put into effect, not all provinces had agreed to such a thing. The British parliament could have created such a requirement if it retained the ability to amend it by a majority, the way that they could put in a supermajority requirement into the Scotland Act given that Westminster could have changed that clause by a majority vote and royal assent, but that was not what happened in 1982 for Canada where Britain renounced any right to legislate for Canada even with its own consent as the Statute of Westminster of 1931 permitted.

It's especially strange as the unanimity clause in the first place for certain kinds of amendments is ludicrously vague, we even have no idea whether it is constitutional to bind the governor general in calling for dissolution of the House of Commons as that could be a legislative power, an executive power, or a crown power, which implicate different amending formulae.

Answer 1

This was answered in the Reference re: Resolution to Amend the Constitution, [1981] 1 S.C.R. 753 (also known as the Patriation Reference).

One of the questions was:

Is it a constitutional convention that the House of Commons and Senate of Canada will not request Her Majesty the Queen to lay before the Parliament of the United Kingdom of Great Britain and Northern Ireland a measure to amend the Constitution of Canada affecting federal–provincial relationships or the powers, rights or privileges granted or secured by the Constitution of Canada to the provinces, their legislatures or governments without first obtaining the agreement of the provinces?

Six members of the Court answered, "yes."

However, these six (Martland, Ritchie, Dickson, Beetz, Chouinard, and Lamer JJ.) did not view the convention as requiring unanimity, but rather, a "substantial degree of provincial consent." While two out of ten provinces was clearly insufficient, the Court declined to provide a precise threshold. Given that this requirement flowed from constitutional convention, the six were of the view that:

it would not be appropriate for the Court to devise in the abstract a specific formula which would indicate in positive terms what measure of provincial agreement is required for the convention to be complied with. Conventions by their nature develop in the political field and it will be for the political actors, not this Court, to determine the degree of provincial consent required.

It is sufficient for the Court to decide that at least a substantial measure of provincial consent is required and to decide further whether the situa­tion before the Court meets with this requirement. The situation is one where Ontario and New Brunswick agree with the proposed amendments whereas the eight other provinces oppose it. By no conceivable standard could this situation be thought to pass muster. It clearly does not disclose a sufficient measure of provincial agreement. Nothing more should be said about this.

In response, the federal government went back to negotiations with the provinces in order to secure the "substantial measure of provincial consent" that the Court observed was required by constitutional convention. In the end, this consent did not include Quebec. Canada has proceeded since on the apparent understanding that this was consistent with the constitutional convention observed by the Court in the Patriation Reference.

Also recall that the only thing Canada (with substantial consent of the provinces) was doing in this process was passing a resolution to ask the Queen to present an Act to the Parliament of the U.K. This would be the Canada Act, 1982, an Act of the U.K. Parliament, which set out Canada's Constitution Act, 1982, along with its amending formulae, and simultaneously terminated the power of the U.K. Parliament to make any further laws with force in Canada. Canada did not enact the Constitution Act, 1982 — it was/is a Schedule to a U.K. act.

On the same day as Canada transmitted the request to Her Majesty, Quebec submitted a reference question that specifically asked whether its consent was required for the passing of a resolution asking the Queen to present the Canada Act, 1982 to the U.K. Parliament. See Reference re : Amendment to the Canadian Constitution, [1982] 2 S.C.R. 793 (the Quebec Veto Reference).

The Court confirmed that Quebec has "no conventional power of veto over constitutional amendments affecting the legislative competence of the Province." One of the requirements for a norm to be elevated to a constitutional convention is that it be accepted by the relevant actors as an obligatory rule that they ought to follow. However, the Court observed that there was no evidence that the convention Quebec was arguing for was recognized by any of the other provinces or federal authorities.