Voters are opting for change at a rapid clip and that's bad news for Justin Trudeau

Not since theGreat Depression disruptedsitting governments across the countryhas any prime minister presided over a period of such sweepingpolitical turnover as Justin Trudeauhas ahead of October's federal election.

Another government could be added to the tally if Dwight Ball's Liberals fail to secure re-election in today's vote in Newfoundland and Labrador a defeat that would make Trudeau's term in office the bloodiest for an incumbent governmentin Canadian history.

Trudeau benefited from a widespread desire for change in the October 2015 election. Since then,there have been nine changes of government in the 11 provincial and territorial elections that have been held during the last four years. (Nunavut and the Northwest Territories do not run elections along party lines, and so have been excluded from this analysis.)

Newfoundland and Labrador was the first out of the gate in November 2015, when Ball's Liberals defeated the incumbent Progressive Conservatives. In 2016, Brian Pallister's PCs beat the NDP in Manitoba and Sandy Silver's Liberals defeated the Yukon Party.

In 2017, Christy Clark's B.C. Liberals won the most seats but were replacedby John Horgan's New Democrats withthe backing of the B.C.Greens. Last year, Liberal governments in Ontario, New Brunswick and Quebec were replaced by the PCs and Franois Legault's Coalition Avenir Qubec.

Already this year, Rachel Notley's New Democrats fell to Jason Kenney'sUnited Conservatives in Alberta, while Wade MacLauchlan's Liberals were defeated by the PCs under Dennis King in Prince Edward Island.

Only the Saskatchewan Party in 2016 and Stephen McNeil'sNova Scotia Liberals in 2017 have managed to win re-election over the last four years.

An unusual pace of change

So muchturnover in such a short period of time is rare. Trudeau's term is only the fourth in Canadian history which saw a majority of provincial elections resultinchanges of government. The others were those ofW.L. Mackenzie King (between 1921 and 1925), Pierre Trudeau (between 1968 and 1972) and R.B. Bennett's single term in power between 1930 and 1935.

Bennett's name is one that Trudeau drops a lot. He has evoked the former Conservative prime minister 19 times in the House of Commons (according to openparliament.ca) toremind the current Conservatives that it was Stephen Harper who had the "lowest growth record" since the market crash of 1929 that sparked the Great Depression.

Harper is the only prime minister whose name Trudeau has uttered more often than Bennett's in the Commons. But Trudeauhas his own connection to Bennett one that does not bode well for his chances in the fall election.

Defeat in the Great Depression

Ten provincial elections were held during Bennett's time as prime minister. Incumbent governments lost eight of them, which was theworst winning recordfor incumbents in history until the last four years.

The early 1930s were a time of tremendous political disruption, in Canada andaround the world. King's Liberals met defeat in the 1930 election in part because of the turmoil triggered by the market crash of the preceding year.

Newly installed as prime minister, Bennett's popularity quickly dropped as his government failed to grapple with the country's rampant unemployment. When he finally went to the polls in 1935, his party lost more than two-thirds of its seats andKing's Liberals were returned to power. The Liberals would stay there for another 22 years.

But Bennett's government wasn't the only one to be sideswiped by the Great Depression.

In 1931, the Liberals were defeated in P.E.I., only to be returned to power four years later with every seat in the assembly after the Conservatives failed to do a betterjob of tackling the upheaval.

In 1933, the Conservatives fell to the Liberalsin Nova Scotia and in British Columbia.

The next year, the Liberals' James Gardiner returned to office in Saskatchewan, replacing the coalition government that brought him down after the 1929 election produced a minority legislature. In Ontario, Mitch Hepburn's Liberals beat the Conservatives, who had been in office for the preceding decade.

Before the federal election in 1935 was held, the Liberals saw off the Conservatives in New Brunswick and "Bible Bill" Aberhart's Social Credit, which proposedradical new monetary policies that were later deemed unconstitutional,was swept to power in Alberta. The incumbent United Farmers were shut out of the Albertalegislature entirely.

It was in this context of turmoil and disruption that Bennett met his political end in October of that year.

The lessons from history

There is no clear relationship between change in provincial capitals and change in Ottawa. In cases where an incumbent government has been defeated in the past, about 32 per cent of incumbent provincial governments changed hands prior. The turnover rate at the provincial level has been about 29 per cent at times when federal governments have been re-elected slightly lower, but not significantly so.

Though Bennett met a catastrophic defeat when the desire for change was sweeping the nation, King won enough seats in 1925to stay in power with a minority government. In 1972, Pierre Trudeau eked out a slim plurality and also stayed in office at the head of a minority government.

On the other hand, a number of prime ministers have met defeat after their provincial counterparts were re-elected.

But it might still worry Justin Trudeau that the country is on pace to match the provincial turnover rate of the Bennett years. Bennett was the last prime minister to be elected to office for the first time at the head of a majority government who was subsequently booted out in the next election. Trudeau wants to avoid being the next one.

And as with the Bennett years, parties that share the prime minister's brand are the ones that are suffering most of the defeats. It will be six Liberal governments down if Ball is defeated today, matching Bennett's record.

Of course, Canada's economy is not now in the depths of a Great Depression. Unemployment currently stands at 5.7 per cent, while estimates put unemployment almost as high as 30 per cent duringthe Depression. But someof the former premiers who have recently become unemployed themselves Philippe Couillard in Quebec, for example were canned despite healthy provincial economies.

In short, weappearto beliving througha Great Disruptionin Canadian politics. It might not be over yet.

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