NDP Leader Jagmeet Singh has written to the Leaders' Debates Commissioner asking him to reconsider his decision to allow Maxime Bernier to participate in the federal election debates.

"I am troubled by your decision to allow the leader of the People's Party of Canada in the debates. It is wrong that Mr. Bernier be given a platform to promote an ideology of hate that spreads prejudice and disinformation," Singh said in his letter.

"Mr. Bernier has courted racists to run for his party. He frequently promotes damaging conspiracy theories on his social media pages. And he has been photographed with far-right hate groups with neo-Nazi ties."

Singh said that Bernier's Twitter attack last month on a 16-year-old Swedish climate activist was also out of line.

On September 2, Bernier posted a series of tweets in which he said Greta Thunberg is "clearly mentally unstable. Not only autistic, but obsessive-compulsive, eating disorder, depression and lethargy and she lives in a constant state of fear."

Singh also said that he disagreed with the commission that Bernier had met the benchmarks required for debate participation.

The commission considers three criteria when deciding which parties should be invited to the debates: whether a party is represented in the House of Commons by an MP who was elected as a member of that party; whether a party is planning to run candidates in at least 90 per cent of ridings; and whether a party has a "legitimate chance" of electing more than one MP.

While Bernier's party has yet to elect a MP under the PPC banner, the commission ruled that it did meet the other two criteria. The decision cited polling data suggesting it was possible that the party might elect more than one member.

The Leaders' Debates Commission was set up by the Liberal government after former prime minister Stephen Harper refused to participate in the English-language debate run by the consortium of TV networks during the 2015 election.

'I look forward to holding him to account': Trudeau

"Stephen Harper and the Conservatives gamed the system to cherry-pick which debates they wanted to do, and what that meant was, there was no national network debate in English that Canadians could watch," Liberal Leader Justin Trudeau said today in St. John's, N.L.

"We made a commitment in that election that we wouldn't let that happen again. That we would create an independent debate commissioner who would organise national debates, official national debates, and make determinations about the format, about who is included in an independent and responsible way," he added.

Liberal Leader Justin Trudeau says he's looking forward to holding People's Party of Canada Leader Maxime Bernier "to account publicly for his intolerant views" in two official debates next month during a news conference in St. John's Tuesday. 1:05

Former governor general David Johnston was appointed commissioner and tasked with establishing a debate in French and another in English. Trudeau has agreed to attend both debates, but did not attend the Maclean's/Citytv debate earlier this month and has not committed to the Munk debate on foreign policy.

Trudeau, however, said he was looking forward to debating the PPC leader. "As for Mr Bernier, I look forward to holding him to account publicly for his intolerant views and I certainly hope all other leaders will do the same."

'I'll be there ready to debate Justin Trudeau': Scheer

Green Party Leader Elizabeth May said the move to include Bernier in the televised English and French debates next month was a "fair decision."

"You couldn't find two party leaders more diametrically opposed than Max Bernier and me. But he has a right to be in the debates," said May at a campaign stop at the University of Waterloo.

"It's a fair decision ... And I respect it."

Once the news of Bernier's inclusion in the debates was made public, the Conservative Party of Canada was quick to object to the decision.

"It's no big surprise that Justin Trudeau's hand-picked debate panel used a Liberal-friendly pollster who attacks Andrew Scheer to ultimately justify Mr. Bernier's attendance at the debate," said Daniel Schow, press secretary to the Conservative leader — apparently referring to Frank Graves of Ekos.

Today Scheer brushed aside questions about Bernier's appearance, saying only that he is focused on debating Trudeau.

"I hope he attends the next one for the Munk debates on foreign policy. He's already missed the first one but I'll be there ready to debate Justin Trudeau and show Canadians why he has lost the moral authority to govern and how a new Conservative government will make life more affordable," Scheer said Today in Winnipeg.

Bloc Québécois Leader Yves-François Blanchet questioned Bernier's inclusion in the debates.

"I do believe that there might be some democratic principles involved here allowing Mr. Bernier to be part of the debates," Blanchet said Tuesday in Longueuil, Que. "However, there are many parties in Canada which have never got anybody elected, which are not invited. So how come Mr. Bernier is there and others are not there?.

"That's kind of uncertain as a decision. But I am not the one to make the rules."