OTTAWA - The British cabinet considered denying Canada's proposal to create a Charter of Rights amid concern that Pierre Trudeau was pushing the plan without the desired backing of the provinces, declassified records show.

The once-secret deliberations of Margaret Thatcher's ministers in the early 1980s — made public by Britain's National Archives — cast new light on Trudeau's ultimately successful effort to patriate the Canadian Constitution.

Tuesday marks the 30th anniversary of Royal proclamation of the Constitution Act, which included an amending formula and the Charter of Rights and Freedoms. The historic milestone was a significant step for Canada as a nation, and also ushered in a new era of entrenched rights for minorities that reshaped the legal landscape.

The British cabinet records show there was considerable constitutional angst not just in Canada, but across the pond, said Eric Adams, an assistant professor of law at the University of Alberta.

"There's this massive tug-of-war going on in which the rules are not clear, and in which politics and law are totally interwoven, and you can see how flummoxed this makes the British Parliament. They wish this issue would go away," said Adams.

"These memos represent the last moments when the British are wringing their hands about the difficult colonials across the ocean that are causing them headaches."

During a British cabinet discussion on Oct. 20, 1981, then-foreign minister Peter Carington told colleagues that Trudeau was talking of "substantial compromise" between the federal government and eight provinces with objections.

Still, "the possibility of such a compromise remained uncertain," the cabinet minutes say.

That was worrisome because the Supreme Court of Canada had just ruled that while the federal government could seek changes to the Constitution without provincial consent, doing so would violate convention.

It was noted during the cabinet session that the Supreme Court ruling "had increased the likelihood of the British Parliament rejecting the Canadian proposals."

The reason: if Ottawa overrode one constitutional convention by pushing ahead without provincial backing, Westminster could not reasonably be bound by another — the long-held notion that Britain was no longer entitled to intervene in Canadian matters.

The Thatcher cabinet feared a parliamentary vote against the Canadian plan.

"If this happened, Britain would be accused of interfering in Canadian affairs and Anglo-Canadian relations would be severely damaged," say the minutes.

As a result, further thought would be needed as to what Britain might do should its legislators reject the Canadian proposals, add the minutes.

"Simple patriation of the Constitution, with the amending formula but without the Bill of Rights proposed by the Canadian Government, might then be the best course."

However, the minutes note such a decision could prompt charges of inappropriate British meddling.

In the end, Trudeau won sufficient provincial support to avert such a crisis in London.

But the cabinet minutes make it clear that securing the Queen's signature on legislation that included a Charter of Rights was never a mere formality.

In October 1980, Thatcher told visiting Canadian cabinet ministers that while Britain would agree to a patriation request even without the support of all provinces, "inclusion of a Bill of Rights was liable to cause controversy and delay in this country," say minutes from November of that year.

Many British Conservative MPs would have been skeptical of an American-style bill of rights, said Adams.

"I think, reading between the lines, it's largely on the grounds that it was something foreign to British constitutional tradition," he said. "Why was Canada abandoning British constitutional tradition and embracing rights? That would have been confounding and disturbing for many of these members of Parliament."

Britain was also wary of wading in while the Canadian courts were deliberating.

At a Nov. 27, 1980, cabinet meeting, Thatcher summed things up by recommending a "personal message" be sent to Trudeau.

It would spell out that while Britain was "firmly committed in principle" to introducing in Parliament "whatever measure" Canada requested — passage would be "greatly eased and speeded up" if the Canadian Supreme Court had first given its blessing.

Still, as Carington wrote in a cabinet memo, Britain had "a major interest" in maintaining good relations with Canada — "an important Commonwealth country with a significant role to play in the Western alliance and on the international scene generally."

"To go back now on what the Canadians will regard as our undertakings over patriation would be to invite a major row."

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