The Balfour Report of 1926 declared that Britain and its Dominions were constitutionally equal to each other. It was a landmark document confirming Canada as a fully independent country, united with Britain and the other Dominions through the Commonwealth.
On 1 July 1867, the Dominion of Canada was established (see Confederation). It comprised a union of the British North American colonies of New Brunswick, Nova Scotia and the Province of Canada (now the provinces of Ontario and Quebec). Other provinces and territories would join later. The Dominion had its own Parliament, but Britain had the theoretical — but never used— power to disallow any legislation it passed.
Britain retained other powers over Canada as well as over other semi-autonomous parts of the Empire. The government in Ottawa, for example, did not fully control Canadian foreign policy. More importantly, only the British Parliament could change the British North America Act, the constitutional statute that underpinned Canada's system of government.
By 1926, the question of who had ultimate constitutional authority had been raised in Canada in the King-Byng Affair, in which Prime Minister William Lyon Mackenzie King had challenged the powers of Governor General Julian Byng — in the context of a heated federal election campaign.
The King-Byng debate was one of the factors leading to the Committee on Inter-Imperial Relations at the 1926 Imperial Conference in London. (See Colonial and Imperial Conferences.) Under the leadership of Lord Arthur J. Balfour, a British Cabinet minister and former prime minister, this committee examined and redefined the legal relationship among self-governing nations of the British Empire.
Mackenzie King and South African Prime Minister J.B.M. Hertzog played a key role in developing the subsequent Balfour Report — an important document in Canada's evolution to fully self-governing nationhood.
"Equal in Status"
The report clarified the new relationship between Great Britain and the Dominions of Canada, South Africa, Australia, New Zealand and the Irish Free State.
“Their position and mutual relation may be readily defined,” the report begins. “They are autonomous Communities within the British Empire, equal in status, in no way subordinate one to another in any aspect of their domestic or external affairs, though united by a common allegiance to the Crown, and freely associated as members of the British Commonwealth of Nations.”
The findings of the report were made law by the British Parliament in the 1931 Statute of Westminster, the founding document of the modern Commonwealth. Canada remained linked to Britain politically and emotionally, but legal power had shifted decisively to the Canadian Parliament and its prime minister. It took several decades before Canada assumed all its powers under the Statute, but fairly quickly this shift led to an independent Canadian foreign policy and to the establishment of its diplomatic service.