MONTREAL -- Quebec's election campaign has been jolted by a report that the province's most famous anti-corruption whistleblower is preparing to enter the race.

There is a report that Jacques Duchesneau has agreed to run for the new Coalition for Quebec's Future in what would be a potentially ground-shifting development.

Duchesneau is the author of two incendiary studies on corruption in the construction industry, its ties to illegal political fundraising and crime groups like the Mafia.

One of his reports has yet to be made public.

The Coalition party said it would not confirm or deny the report in the Globe and Mail that it had recruited, as an election candidate, the man who last year played a pivotal role in prompting the current government to call a corruption inquiry.

"My candidates will all be announced by Tuesday," Coalition Leader Francois Legault said, grinning broadly Friday.

"I have nothing to announce today."

He did salute Duchesneau's "integrity."

An ex-Montreal police chief, Duchesneau had been hired by the Charest Liberals and he produced a report on how the construction industry was bilking the public purse and illegally funding political parties.

That report was leaked to the media. It created such a sensation last fall that, after two years of refusing to call a public inquiry, Charest finally relented.

Duchesneau made waves again in June when he revealed that he was the person who leaked the document. He testified at the inquiry that he gave it to a journalist because he was convinced the government wouldn't do anything with it.

A former policeman, federal civil servant and mayoral candidate, Duchesneau has a history of public spats with several of professional colleagues, including the provincial government and Montreal Mayor Gerald Tremblay.

The Coalition, which is participating in its first election campaign, recently led opinion polls with its promise to shelve the independence debate and bring together Quebecers of federalist and separatist backgrounds to tackle other pressing issues.

It had recently slumped to third place and risked being sidelined in the news coverage in the first days of the campaign. Until Friday.

There was a quick example of the impact Duchesneau's candidacy would have on the race.

The Parti Quebecois held a news conference to introduce its economic team of candidates and the event was overshadowed by questions about another party's supposed candidate.

PQ Leader Pauline Marois reacted warily to Duchesneau's reported entry in the race.

"I'd be a bit stunned because he said he would not be returning to politics," she said citing Duchesneau, who had suggested his political career was over after a defeat in Montreal municipal politics.

If it happens, Marois said his candidacy would harm the Liberals and not her party: "I believe the Parti Quebecois has been very clear on the integrity issue," she said.

Every party has tried to claim ownership of the ethics issue.

The PQ has promised a democratic-reform package that includes $100 limits on political contributions, voting at age 16, and referendums initiated by citizens who collect petitions. The Liberals have pointed to the anti-corruption squads they created, the inquiry, and to numerous pieces of legislation they passed to tighten political fundraising and oversight of public contracts.

After news reports about wrongdoing in municipal politics and construction, the Charest Liberals created an anti-collusion unit in 2010. They hired Duchesneau to run it. He was later transferred to a new, larger anti-corruption squad but was fired after run-ins with his new boss.

He has since said that he was so disturbed by the scope of corruption that even after he was fired by the government he continued to work, as a volunteer, on a second volume of his report.

He said he received tips from members of the public and made about 50 pages of notes from informants describing illegal schemes in the construction industry and political financing.

He produced a second report that has never surfaced publicly. He tabled it with the inquiry in June and it was to receive a fact-checking before being published for public consumption. For now, the document is being treated not as evidence tabled before the inquiry but as a tip from the public.

Duchesneau's still-secret report is titled, "The illegal funding of political parties: A hypocritical system where influence is awarded and decisions are for sale."

So far his most sensational allegation has been that 70 per cent of money raised by Quebec political parties is done illegally and that "dirty money" is the norm.

While testifying in June, he cited one vivid image relayed to him by one of his investigators: an unnamed municipal party was so flush with fundraising cash that it couldn't close the door of its safe.

But he has yet to provide specific names from the world of politics. His so-far-untested allegations have prompted an aggressive pushback.

He was grilled at the inquiry by lawyers for the Quebec government and the opposition Parti Quebecois, and challenged to show evidence for his claims.

Duchesneau snapped at the government lawyer at one point. None of the lawyer's questions were about corruption -- but focused instead on things like administrative details about the office he ran.

"The enemy is the people I spent 18 months tracking," Duchesneau said in June. "All these questions are really funny. We point out collusion to you, and what you're looking at is my finger -- not where we should be going.

"That's what's sad."