Which historical document is a major influence on Canadian law?

The Constitution Act, 1867 is a major influence on Canadian law because it establishes the foundational framework for the governance of Canada and outlines the distribution of powers between the federal and provincial governments. This act marked the beginning of Canada’s journey toward becoming a self-governing dominion within the British Empire, significantly shaping the country's legal and political landscape.

As part of the Constitution, it sets forth the principles of responsible government and the structure of the Canadian legal system. It includes key provisions concerning the division of responsibilities, the creation of federal and provincial legislatures, and the establishment of a parliamentary democracy, which are crucial for the functioning of Canadian law today.

While the Charter of Rights and Freedoms plays a vital role in protecting individual rights and freedoms within the context of the Canadian Constitution, it is integrated into the larger framework set out by the Constitution Act, 1867. The BNA Act (British North America Act) is essentially another name for the Constitution Act, 1867, thus it does not represent a separate influence but rather a historical designation. The Magna Carta, while historically significant for the development of common law and principles of justice overall, does not have the same direct impact on Canadian law as the Constitution Act, 1867.