If all had gone according to his grandmother’s plan, Murray Sinclair, the Anishinaabe jurist who did as much as any figure in the country’s history to right the troubled relationship between Canada and Indigenous peoples, would have been a Catholic priest. Instead, Mr. Sinclair dedicated himself to law and justice, charting a collision course with some of Canada’s most sacred institutions, including his grandmother’s church, which was shaken to its Vatican foundations by the Sinclair-led Truth and Reconciliation Commission, completed in 2015.