Over the weekend, the Quebec election campaign transformed into a referendum on the credibility of François Legault, whose Coalition Avenir Québec is leading in opinion polls.

On Saturday, and then again on Sunday, Legault flubbed factual questions about Canadian immigration policy, even though his proposed reforms to that policy are a centrepiece of his party's platform.

Monday's English-language debate offered a taste of what the next several days hold in store for Legault: it's not going to be fun.

For extended periods, it was open season on Legault as both Liberal Leader Philippe Couillard and the Parti Québécois's Jean-François Lisée hammered him on his immigration policies.

During an exchange about Quebec's labour shortage, estimated at 90,000 unfilled jobs, Legault stood by his promise to lower immigration levels by more than 20 per cent and expel newcomers who fail to learn French within three years.

"It is appalling," Lisée said of the CAQ plan to force non-French-speaking immigrants to leave the province. Couillard quickly turned it into a Legault pile-on.

"We know you don't understand immigration," the incumbent premier said.

Lisée and Couillard tag-teamed their volleys at Legault several times during the debate, whenever the immigration issue came up.

And Legault wasn't always sure where he should direct his return fire.

CAQ Leader François Legault, seen here speaking to the media after the English-language debate, is likely to find himself pressed on his knowledge of policy and his command of facts in the two weeks left in the campaign. (Ryan Remiorz/Canadian Press)

More than just another gaffe

The attacks on Legault's immigration proposals are nothing new, of course. They produced some of the saltiest moments during Thursday's French-language debate, as well.

But Legault's gaffes over the weekend changed the significance of these criticisms.

Immigration, according to most accounts, is not the number one priority of most voters.

Couillard has been trying to make hay with the issue for at least two weeks, to no noticeable effect in the polls.

When Legault exposed his hazy understanding of the nuts-and-bolts of immigration rules, though, the questions ceased being about the merits of his proposals.

Instead, they're about whether Legault knew enough about how Canadian immigration works before drafting a policy that could have far-reaching effects on Quebec's economy, not to mention its social fabric.

Or, put more simply: Does he have credibility in the eyes of voters when making campaign promises?

That's a question that is more likely to resonate with Quebecers than at what point in the immigration process a Quebec selection certificate ought to be handed out.

Is it fun being François Legault?

The reaction from Legault's camp to the flubs was swift, and hinted at the danger his associates sense in this line of questioning.

Before Monday's debate, the CAQ's Granby candidate, François Bonnardel — one of Legault's faithful lieutenants — insisted to reporters that his leader was "an expert at immigration."

Stéphane Gobeil, a senior campaign adviser, tweeted out results of a current affairs quiz the four leaders took for La Presse back in July. Legault scored the highest.

Il paraît que <a href="https://twitter.com/JFLisee?ref_src=twsrc%5Etfw">@JFLisee</a> veut faire de la crédibilité la question de l'urne. <br>Il a échoué son test de crédibilité en ratant toutes les questions économiques de <a href="https://twitter.com/LP_LaPresse?ref_src=twsrc%5Etfw">@LP_LaPresse</a> <a href="https://twitter.com/hashtag/polqc2018?src=hash&ref_src=twsrc%5Etfw">#polqc2018</a> <a href="https://t.co/vHrNg3DMVb">pic.twitter.com/vHrNg3DMVb</a> —@gobeillades

Legault did not make any major missteps in Monday's debate, and so may have stanched the bleeding from the weekend's self-inflicted wounds.

But he shouldn't get too comfortable. Not only have his two principal rivals identified a weakness, but the public, too, has questions about his readiness for the top job.

He will be pressed on his knowledge of policy, on his intelligence, on his command of facts and figures.

No, it didn't look like it was much fun to be François Legault on Monday night. And it probably won't be for the next few days.

But if he can put to rest doubts about his credibility, Oct. 1 might still be very fun for him indeed.

Missed the debate? You can watch it here:

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