Former RCMP chief superintendent Ben Soave told a French national television network that organized crime has infiltrated Ontario at least as much as it has in Quebec, if not more.
Ontario has the same organized crime groups involved in corruption, and they are probably even more active than in Quebec, he said.
But if there is any truth to such allegations, McGuinty said he wants to know about it.
"If there are serious and warranted allegations they need to be made in a substantive way, not through the media," he said Tuesday at the International Plowing Match in Ayr, Ont.
"I would expect that people in positions among our police services would be drawing this to our attention at the earliest possible opportunity."
Soave — who retired from the RCMP in 2005 and is now the head of a private risk-management consulting company — said he's concerned about the silence surrounding the significant presence in Toronto of the 'Ndrangheta, an affiliate of the Calabrian branch of the Mafia.
Ontario has the same problem, the same corruption, but the Mafia are simply more discreet, Soave said.
Provincial politics, the police, the justice system, the manufacturing sector — none has escaped the Mafia's influence, he added.
"Sometimes politicians are very naive," Soave said in French. "They are not wary of the danger or risk and they shake hands and accept money."
McGuinty said he has "no reason to believe" that police would want to keep such allegations quiet or confidential if they are, in fact, grounded in reality.
"I would think they would have approached us in a constructive way some time ago," he said.
Opposition Leader Tim Hudak said he's never seen anything like that among his political colleagues in the legislature.
"Any time you hear that, obviously you're concerned and hopefully if there's more information to come forward, it will come forward," he said.
NDP Leader Andrea Horwath said she was troubled by Soave's comments.
"That's an allegation that I think we have to take very seriously, and it's quite concerning," she said.
"I would hope that if anybody has any information that corroborates that suspicion, that they come forward and let the public know and let the politicians know, let the government know, let the police know, let the OPP know what they know in terms of any particular individuals."
Ontario is no stranger to organized crime, particularly in its biggest city. But allegations of political corruption are rarely heard.
A corruption inquiry in Quebec is looking into links between the construction industry and organized crime.
Valentina Tenti, an expert in the Italian Mafia, testified Tuesday at the Charbonneau inquiry that the 'Ndrangheta has a strong presence in Canada, particularly in Toronto and Thunder Bay, Ont.
A police officer from York Regional Police will also discuss the Mafia in Ontario later this week.
The commission has heard explosive testimony from Jacques Duchesneau, the former police chief who said more than two-thirds of political party funding was done improperly.
Quebec's former anti-collusion investigator wrote a report tabled one year ago that forced outgoing premier Jean Charest to call a corruption probe.
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