When does Justin Trudeau become prime minister?

Constitutional tradition means the Liberal leader doesn't have to hurriedly get packing

Prime minister-designate Justin Trudeau attends his first official news conference at the National Press Theatre in Ottawa, Tuesday Oct.20, 2015. THE CANADIAN PRESS/Adrian Wyld

Incoming prime minister Justin Trudeau attends his first official news conference at the National Press Theatre in Ottawa on Oct.20, 2015 (THE CANADIAN PRESS/Adrian Wyld)

The Liberals under Justin Trudeau won the most seats in the 2015 election. So does that automatically make Trudeau the prime minister?

Not so fast. In a constitutional monarchy such as Canada’s, the conventions and precedents governing a change of office are deliberately vague in order not to exclude any possible electoral result. In the end, the Liberal majority meant constitutional scholars weren’t needed to figure out who gets power.

Technically, Stephen Harper was still Prime Minister on Oct. 20. While news organizations bestowed on Justin Trudeau the title prime minister-designate, for all intents and purposes, he woke up as simply the leader of the Liberal party. He’ll get a title upgrade to prime minister on Nov. 4, since, less than 24 hours after the election, Trudeau announced that he’d unveil his cabinet on that day. And Rideau Hall, the official home of Governor General David Johnston, confirms that will also be when the Liberal leader and his cabinet are sworn in at Rideau Hall. Thus, it will also be when Harper ceases to use the prime ministerial title.

“The formal resignation of the outgoing prime minister, which also covers that of ministers, is submitted to the Governor General very shortly before the swearing-in of the new prime minister,” the vice-regal website states. The oath that Trudeau will take is set out in the Oaths of Allegiance Act: “I, [name here], do swear that I will be faithful and bear true allegiance to Her Majesty Queen Elizabeth the Second, Queen of Canada, Her Heirs and Successors. So help me God.” And yes, there’s a version for those wanting to affirm rather than swear their loyalty. He’ll also swear an oath to be a member of the Privy Council. And another for taking on the job of prime minister. 

Until then, Trudeau is preparing to take office, while Harper continues with his duties as Prime Minister. That is why, on Oct. 22, Harper and Trudeau appeared together during ceremonies at the National War Memorial commemorating the first anniversary of the deaths of Cpl. Nathan Cirillo and Patrice Vincent. Harper was there as Prime Minister, Trudeau as the prime minister-designate.

In a break with tradition, Trudeau and his family won’t move into 24 Sussex. The PM’s residence is getting a much-needed, much-demanded overhaul. It’s riddled with asbestos and needs a new heating and cooling system, as well as basic structural work. Even the cliff on which it stands is crumbling. The Trudeau family will “make do” with Rideau Cottage, a two-storey Georgian-revival brick home on the grounds of Rideau Hall, the Governor General’s estate in Ottawa. Traditionally the home of the GG’s secretary, it is such a short walk to the residence of the Queen’s representative in Canada that pundits and constitutional experts took to Twitter to explore potential “conflicts” for Trudeau and Johnston.

The actual post-election change of power is relatively straightforward. As University of Ottawa constitutional scholar Adam Dodek explained recently, “By constitutional convention, the Prime Minister will still be the Prime Minister on Tuesday morning, and remains so until he decides to resign, or he is fired by the Governor General. It would certainly be acceptable constitutionally, if he wanted to continue in office until he met the House and faced a vote of confidence, even if he finished second or third in the polls.”

Harper wasn’t going to try his luck in the House. He already offered his resignation as leader of the Conservative party on election night. But there is still protocol, and vice-regal etiquette, to be followed. At this point in the transition, the timing of events is the bailiwick of the Governor General, in this case, David Johnston, who was asked to stay in office a bit longer than expected because of the possibility of a political cliffhanger.

“When a prime minister is defeated or decides to resign from office, he or she indicates his or her intention to resign to the Governor General,” explains the Rideau Hall website. “In the case of a prime minister informing the Governor General of his or her wish to retire and to resign from office, the Governor General, in accepting the resignation, may seek the prime minister’s advice as to a successor [as prime minister]. The Governor General then decides who is in the best position to command the confidence of the House of Commons, and invites that person, during a meeting at Rideau Hall, to form a government.”

Whom Johnston would invite to form a government is obviously not in doubt. The timing of the swearing-in ceremony is largely a matter of syncing calendars of all concerned. When Harper won the 2006 election, it took him about two weeks to make the trek to Rideau Hall for the swearing-in. Before that, it was the turn of the Liberals, under Jean Chrétien, back in 1993. Then, the switch was a lot faster. The election was on Oct. 25 and, by Nov. 4, the new PM was settling into his new work digs in the Langevin Block.

As for Trudeau, who is also picking Nov. 4 as the day power changes, he’ll have little time to settle into the job before hitting the world stage. The G20, the Commonwealth leaders’ summit in Malta, and the climate change conference in Paris are all coming up in the next few weeks. But his first large public event will be in Ottawa. He and the GG will be at the National War Memorial for the Remembrance Day service on Nov. 11.

NOTE: This story, originally written on election night of Oct. 19, was updated throughout with new information on Oct. 22, as well as Oct. 27.

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