TORONTO — Retired Supreme Court Justice Louise Arbour was installed as Canada’s next governor general on Monday after a swearing-in ceremony.

The governor general is the representative of Britain’s King Charles III. The king is the head of state in Canada, a member of the Commonwealth of former colonies.

Arbour, 79, replaces Mary Simon, who became Canada’s first Indigenous governor general in 2021. The governor general has important constitutional duties, but the job is mostly ceremonial and symbolic. Prime Minister Mark Carney picked a Francophone for the job.

The Central Band of the Canadian Armed Forces played “God Save the King” and the Governor General’s Flag was raised on Parliament Hill to mark the moment.

Arbour is a world-renowned legal scholar, judge and leader in human rights and justice. She was appointed as a judge to the Supreme Court of Ontario, the Court of Appeal for Ontario, and the Supreme Court of Canada.

In 1996, the United Nations selected her as Chief Prosecutor of the International Criminal Tribunals for the former Yugoslavia and Rwanda. She led efforts that resulted in the first conviction for genocide since the 1948 Genocide Convention and the first indictment for war crimes of a sitting head of state.

She later served as a U.N. Special Representative for International Migration from 2017 to 2018.

In her first speech today as the King’s representative in Canada, she said the ability to coexist peacefully despite differences was critical to maintaining a lawful, rules-based society.

Arbour also discussed the rapid growth of artificial intelligence and cautioned against overreliance on the technology. She said that with instant access to vast amounts of information, it is very tempting to pay little attention to the reliability of sources.

“The lines between knowledge and belief, between truth and falsehood, between facts and assumptions are increasingly blurred,” Arbour said. “AI could be threatening not only the way we live and work, but also the control we exercise over our own destiny.”

She noted that Canada covers nearly 7% of the world’s landmass, holds 20% of its freshwater, and yet makes up just half of 1% of its population.

She said the world “looks at us with justifiable envy.”

Arbour met with King Charles at Buckingham Palace last week.

After the United States gained independence from Britain, Canada remained a colony until 1867 and afterward continued as a constitutional monarchy with a British-style parliamentary system.