On November 13, 1992, he was appointed to the Supreme Court of Canada by Prime MinisterBrian Mulroney. During much of his time of the Court, he was a comparatively low-key judge. He was known for his belief in providing deference to government and for his particularly succinct writing style. Major stepped down from the court on December 25, 2005, approximately two months early.
On January 5, 2006, he rejoined the Calgary office of Bennett Jones LLP, the firm with whom he practised before his judicial career. On March 8, 2006, he was appointed by Prime Minister Stephen Harper to lead a public inquiry into the Air India Flight 182 bombing and the resulting trials. He was made a Companion of the Order of Canada in the Canada Day 2008 Honours.