The question before the House is whether Canada should have its own constitution, with a new Bill of Rights attached.

"Canada Island has been a sovereign country, Mr. Speaker: it displays all the proper characteristics of a free nation and has acted accordingly," the member of parliament says. "Therefore, I implore parliament to agree that Canada be emancipated from the remnants of colonialism."

The member's party applauds thunderously, in the tradition of parliamentary debate. A pause, then a member from the opposing party rises.

"Mr. Speaker, the Honorable member has failed to address the central issue here, conflating the principles of democracy," the oppositionist begins. "The government of Canada wishes to expedite the constitutional matter without obtaining the appropriate consent of the provinces--the sum of the nation's parts. I ask you, is this any way for a responsible government to proceed?"

THE ABOVE EXCHANGE is purely hypothetical, but it represents in roughest form the core of the Canadian constitutional debate. The possibility that at once embarrasses and frightens most Canadians right now is that the above debate will be played out not in Ottawa, but in London. London, England. Rather than the party led by prime minister Pierre Trudeau battling to a verdict with the party led by Joe Clark, the final decision on the status of a Canadian constitution may come to rest with the followers of Margaret Thatcher and the followers of Michael Foot.

It is ironic in the extreme that one of the most prosperous Western democracies, with an admirable record both abroad and at home, may be placing its destiny in the hands of Britain, evoking the days the empire was spelled with a capital "E." But that is the plausible consequence of the Canadian Supreme Court's recent decision, handed down September 28, which declared that Trudeau can legally proceed with his package of constitutional reforms, although he would violate convention if he did so without the expressed consent of most of the provinces. The ruling, often muddled in its reasoning but typically Canadian in its effort to compromise, in effect vindicated all sides in the contentious constitutional dispute. Everyone won; everyone lost. And the court left open the possibility that Britain will determine the final outcome.

If this seems confusing at first blush, consider a few preliminary facts: Since 1931, Britain has not exercised any influence in Canada beyond, well, stirring the loyalists with a Royal Wedding or two. And since 1931, Canadian governments have tried unsuccessfully to hammer out an indigenous constitution acceptable both to the federal branch and the provincial branch. Trudeau, a former lawyer who has held power with the federal Liberals for all but a few months in the past 14 years, has long dreamed of enshrining a civil Bill of rights together with a constitution the country can call its own. As it stands, the British North America Act of 1867 acts as Canada's de facto constitution.

THE KEY STICKING point between Trudeau and the eight provincial premiers who oppose his initiative is over the establishment of an equitable formula for amending the nascent document. Except for New Brunswick's Richard Hatfield and Ontario's William Davis, the provincial premiers fear the new constitution could erode their power by increasing the leverage of the central government. Furthermore, another dimension should be noted: The constitutional package forms the crux of Trudeau's response to the separatist movement in Quebec and the growing regional loyalties of the resource-rich, solidly Conservative West. If the constitution is indeed brought home, on Trudeau's reasoning, Canadians will be able to share common rights without having their particular identities threatened. Francophones could be proud of their language and distinct culture, Westerners could be proud of their regional heritage, immigrants could preserve their native identities--but in a primary, basic sense, they would all be Canadians.

Trudeau had proved unable to gain the consent of the provinces and had assumed the role of the bold maverick, vowing to plow ahead with his plans regardless of the opposition. With a comfortable federal majority, he can pass the legislation and then send it on to Britain for what should be routine ratification. The provincial premiers naturally challenged the legality of Trudeau's proposal to proceed unilaterally, and the case naturally fell into the laps of a squirming Supreme Court. In the meantime, Trudeau's opponents--the federal Conservative party and the provincial premiers--started writing letters to British MPs, asking that they refuse to rubber stamp Trudeau's package. Even before the court announced its decision, British members were crossing the Atlantic, coming to Canada on fact-finding missions. Presumably, Britain's honorable members have had trouble enough tending to their own garden recently without these gratuitous vacations.

THAT THE SUPREME COURT decided was that a convention existed for the federal government to gain the consent of the provinces before going ahead with constitutional changes that would affect their power. By a vote of 6-3, the court ruled that Trudeau would violate the spirit of tradition by unilaterally setting his plan in action.

By a vote of 7-2, however, the courts decided that if Trudeau were to proceed, he would not be violating the letter of the law. As the earnest students who haunt Langdell and Roscoe Pound would say, the bottom legal line is all that counts.

On Thursday, Trudeau offered to convene a federal-provincial conference once more to attempt to reach an agreement on the constitution, noting the court's qualified judgment. The provincial opponents have indicated they will probably decline, making it more likely than ever that the crucial struggle will take place in British parliament. Not only does this put Canadians in an embarrassing position, it also puts them in an unpredictable position.

The main issue lost in the heated debate in Canada over the past two weeks is the question of convention. The British North America Act, while a suitable half-measure, by no means composes an adequate constituion. For instance, most Americans, well schooled in constitutional liberties, probably assume that freedom of speech is a sacred principle in Canada. It is--but by convention, not by law. Or, a foreigner might assume that when an incumbent federal party loses its majority in an election, it must automatically turn over the reins of power to the winning party, and that the incumbent prime minister must resign. Again, this is true only by convention, and not by law. The technical, though merely nominal, power to form any government lies with the Governor-General, the monarch's very own representative in Canada (a spot now occupied by Canadians--by convention).

THE CONSEQUENCE and the underlying contradiction of the court's ruling, then, is this: Having found a new convention, it endangers an old and vital convention, namely, that Britain plays no active part in the country's business. If the British parliament intervenes on the issue of the constitution, it will set a precedent. What will stop it from intervening on the issue of an election--for example, to keep a friendly party in power even after that party has lost a Canadian election? Or to defeat a budget whose policies might prove disadvantageous to Britain? Or to siphon off Canadian resources in order to help a flagging British defense establishment?

The philosophical distinction between the rule of law and the rule of morality is important and eternally debatable. But in the realm of convention, the court has laid bare the possibility of England wresting away Canada's control of her own destiny. Since the constitutional debate is highly politicized, Canadian politicians must absorb some blame for the plausibility of such an occurence. But the British parliament should abide by Trudeau's decision, whether or not he manages to attract provincial consent. England out of Canada.