The official Leaders' Debates Commission has decided to invite Maxime Bernier, leader of the People's Party of Canada, to participate in the English and French debates that will be televised next month.

"You have satisfied me that you intend to field candidates in 90 per cent of ridings and, based on recent political context, public opinion polls and previous general election results, I consider that more than one candidate of your party has a legitimate chance to be elected," David Johnston, the former governor general who leads the commission, wrote to Bernier on Monday.

Bernier was not initially included among the leaders invited to participate in the debates. Instead, he was asked to provide more information as the commission considered his case.

"Canadians will be able to see all the options before voting the 21st of October. And it is important," Bernier told supporters at a meeting in Saint John, N.B. "I must say to Mr. Johnston that he took the right decision for the future of our country."

Not all debate participants were happy to see Bernier join them.

"I think it's wrong to give Mr. Bernier the platform to spread his hateful and divisive message," NDP Leader Jagmeet Singh said during a campaign stop in Montreal. The NDP made a submission to the commissioner in July that raised concerns about Bernier's political views.

WATCH: Singh says 'it's wrong' to include Bernier in debates

NDP Leader Jagmeet Singh says it's wrong for the Leaders's Debate Commissioner to include People's Party of Canada Leader Maxime Bernier in two official debates because it gives him "the platform to spread hateful and divisive messages." 0:11

Bernier's former colleagues in the Conservative Party also criticized 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.

"Our Liberal team appointed former Governor General, the Right Honourable David Johnston, to lead the new debate Commission so decisions on participation for the two official debates would be made independently," a Liberal party spokesperson said in a statement. "We look forward to continuing to share our positive, forward-looking and inclusive vision with Canadians."

The commission's two debates will be hosted by a partnership of media organizations, including the CBC. The English-language debate will be broadcast on the evening of October 7. The French-language debate will occur three days later on October 10.

David Johnston, the former governor general who was appointed to lead the commission, extended invitations last month to Liberal Leader Justin Trudeau, Conservative Leader Andrew Scheer, NDP Leader Jagmeet Singh, Green Leader Elizabeth May and Bloc Québécois Leader Yves-François Blanchet.

The commission was charged with considering three criteria as it decided on a final list of debate participants: 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.

To be included in the debates, a party must satisfy at least two of those criteria.

Bernier and the People's Party have nominated candidates for more than 90 per cent of the country's 338 ridings, but the party has not yet elected an MP under its banner (Bernier was elected as a Conservative MP in 2015).

That left the commission to decide whether the People's Party had a "legitimate chance" of electing multiple MPs this fall.

"At this time in the electoral cycle, we do not consider that the People's Party of Canada has a legitimate chance of electing more than one candidate in the next federal election," Johnston said in a letter to Bernier in August.

Bernier was invited to submit to the commission a list of three to five ridings where the People's Party had a chance at success.

In addition to Bernier's riding of Beauce, the commission reviewed opinion polling results for the Ontario ridings of Nipissing-Timiskaming, Etobicoke North and Pickering-Uxbridge, and the Manitoba riding of Charleswood-St.-James-Assiniboia-Headingley.

The results of those riding-level polls, conducted for the commission by Ekos, showed that between 24.5 per cent and 34.1 per cent of respondents said it was "possible" that they would vote for the People's Party candidate.

According to a separate analysis, drafted by Nanos Research for the commission, it's possible for a party to win a riding if a quarter of voters there are willing to consider voting for the party's candidate.