Another minority government looks likely, but it could be very different from the last one

Canadians have chosen minority governments in four of the last six federal elections, and Monday's vote seems likely to produce a fifth.

Whether it will be a Liberal or Conservative minority is anyone's guess.

Polls suggest the two parties are locked in a dead heat, neither within reach of winning a majority of seats in the House of Commons — much as they were in 2019, when Justin Trudeau's Liberals won a relatively stable minority.

But that doesn't mean this election will produce the same result.

Here are some things to keep in mind about how minority governments are formed and what another one might look like.

Popular vote vs. most seats

Which of the two front-runners ultimately forms government doesn't necessarily depend on who wins the greatest share of the popular vote or even who wins the most seats.

Rather, it depends on which party can command the confidence of the House, notes University of British Columbia political scientist Maxwell Cameron.

And that means: which party is able to muster enough support from one or more smaller parties to win crucial confidence votes?

Trudeau has the right to carry on

If he were to see little prospect of mustering sufficient opposition support to continue governing, Trudeau would likely resign and allow the Conservatives to form government.

Regardless of the outcome, Trudeau has the right to carry on until he is defeated in a confidence vote in the Commons. Opposition parties would get their first opportunity to topple his government by voting against the throne speech, which opens each new session of Parliament.

If the throne speech was defeated, it would be the prerogative of the Governor General to invite Conservative Leader Erin O'Toole to form a new government. O'Toole would then have to gain support from one or more of the other opposition parties in order to command the confidence of the House. If he could not, another election would be triggered.

Will other parties prop up a government?

In 2019, the Conservatives actually won a slightly larger share of the popular vote, but because so much of it was concentrated in the Prairie provinces, they came up with 36 fewer seats than the Liberals.

There was never any suspense about whether the Liberals would continue to govern. They were only 13 seats short of a majority and NDP Leader Jagmeet Singh, whose party captured 24 seats, had been clear during the campaign that New Democrats would never prop up a Conservative minority.

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Trudeau was able to govern without reaching any formal deal with opposition parties, relying on support from different parties at different times to survive confidence votes and pass legislation.

Singh has not ruled out propping up the Conservatives this time. Nor has Bloc Quebecois Leader Yves-Francois Blanchet.

Although O'Toole has shifted the Conservatives more toward the centre of the political spectrum, Cameron suspects it would still be harder for him to find a dance partner in the Commons, since both the Bloc and NDP are more ideologically aligned with the Liberals.

However, Quebec Premier Francois Legault's virtual endorsement of the Conservatives could influence the Bloc to give O'Toole a chance to move into the Prime Minister's Office.

Possible scenarios

So what would happen if the NDP were to back the Liberals and the Bloc were to back the Conservatives, but neither of the front-runners could muster majority support in the Commons?

In that case, it's theoretically possible that a handful of Green Party or People's Party MPs could determine which of the front-runners forms government.

The further either of the front-runners is from the 170 seats needed for a majority, the more leverage the smaller parties would have to make demands in return for their support.

There are three approaches to minorities, notes Cameron, the most common being the informal vote-by-vote approach taken by Trudeau during the past two years. Cameron suspects that would be the likely approach again should Monday's election produce another minority.

However, it's possible that Trudeau or O'Toole might be compelled to go further, negotiating an agreement with one or more smaller parties to prop them up for a period of time in exchange for specific legislative action.

That's how David Peterson's Liberals took power in Ontario in 1985, striking a two-year deal with the NDP to oust the Conservatives, who had won the most seats.

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It's also how John Horgan's NDP won power in British Columbia in 2017, ousting the Liberals, who had won the most seats by securing the support of the Greens' three members of the legislature.

Coalition?

It's also possible that the smaller parties could demand to be part of a coalition government. But coalitions, while common in other countries, are rare in Canada, where the notion has been tainted by an aborted attempt to unseat Stephen Harper shortly after he won a second Conservative minority in 2008.

At that time, the Liberals and NDP negotiated an agreement to form a shaky coalition government, but since both parties combined still fell short of a majority, they had to secure a promise of support from the separatist Bloc Quebecois. Further complicating matters, the would-be coalition prime minister, Stephane Dion, had already resigned as Liberal leader.

Harper railed about the coalition as an affront to democracy, effectively characterizing it as an attempted separatist-backed coup and winning the public relations war. He then persuaded the Governor General to prorogue Parliament, buying himself some time.

By the time Parliament resumed, Dion was gone, the Liberals had gotten cold feet and the coalition agreement fell apart.

While the smaller parties might be tempted to make stiff demands in return for their support, Cameron thinks their bargaining power would be limited by the fact that no one would want to plunge the country into yet another election in the midst of the fourth wave of COVID-19.