The Supreme Court noted that when the British North America Act was originally adopted, there were "few, if any" Inuit in Canada, which was then a much smaller country.
It argued that the term "Indians" as defined by the Royal Proclamation of 1763 would not include the Inuit, and that this document could be used to help interpret the British North America Act.
Later, after the British North America Act was adopted, the Parliament of Canada declared in December 1867 that if it gained jurisdiction over Rupert's Land, it would take responsibility for the Indians there.
Duff then added that the Inuit of Labrador, as well, had been widely referred to as Indians from around 1760 and were when the British North America Act was adopted.
In 1869, a judge from the Court of Labrador prepared a report for the Governor of Newfoundland which referred to "Esquimaux" (Inuit) as a type of Indian.
Duff also doubted that the Royal Proclamation of 1763 could guide interpretation of the British North America Act.
Justices Albert Hudson and Henry Hague Davis each wrote brief opinions concurring with Duff.