How did the Canada Act of 1982 end the remaining British control over Canada’s constitution?

The Canada Act, approved by the British Parliament in 1982, served as the final step in severing Canada's remaining legal ties to Great Britain, establishing the country as a fully sovereign state.1

Prior to this act, Canada’s constitution was based on the British North America Act of 1867, which required the British Parliament to pass amendments. The 1982 act ended this dependency by:12

• Establishing a Domestic Amendment Formula: It provided a mechanism for Canada to amend its own constitution without British involvement, requiring resolutions from the Canadian Parliament and the concurrence of two-thirds of the provinces representing at least 50 percent of the population.1
• Entrenching Rights: It introduced the Charter of Rights and Freedoms, which codified 34 rights to be observed across the country.1
• Full Sovereignty: By incorporating the original 1867 statute and subsequent amendments into a new domestic framework, the act ensured that Canada no longer relied on the British Parliament for constitutional changes.1

Queen Elizabeth II proclaimed the act on April 17, 1982, marking the end of British legislative control over the Canadian constitution.1