A public inquiry will probe allegations of pervasive corruption in Quebec, Premier Jean Charest announced on Tuesday, following two years of rumours linking government contracts to well-connected businessmen and even organized crime.

Superior Court Justice France Charbonneau will run the long-awaited inquiry, which will have both public and private hearings and is expected to deliver its findings in 2013.

However, the hearing will not have the power to force anyone onto the stand, leading critics to ponder how effective it will be at unveiling corruption.

When asked about how the probe's limited mandate, Charest said that three key criteria went into the creation of the proceedings.

"We did not improvise," Charest said at a press conference in Quebec City on Wednesday. "Serious thought was put into this."

At his press conference, Charest told reporters that he will testify if asked.

Charest explained that the probe has been designed to protect police evidence already collected, along with the witnesses themselves. Charest added that officials want to ensure that any evidence presented at the hearings can also be used in later criminal investigations.

Witnesses who testify will not be granted any immunity from criminal charges.

Charbonneau, who is a well-respected judge and a former prosecutor, made a name for herself during the prosecution of Maurice "Mom" Boucher, a convicted killer and reputed biker boss.

The corruption probe will stretch back 15 years, to when the Parti Quebecois was in power.

Antonia Maioni, from McGill University, said that suspicions of corruption and collusion among the construction industry and the government had been "relentless" over the past two years, forcing action from Charest.

"While the announcement is historic and a big moment in Quebec, it has been a long-time coming," she told CTV's Power Play.

"Jean Charest has really been seeing his numbers fall spectacularly in the polls, in terms of public confidence in him and his party, so in many ways, he had no choice but to call that inquiry today," Maioni said.

Maioni noted that the hearings cannot force anyone to testify, as officials are unwilling to grant immunity for witnesses from future criminal prosecutions.

"This commission of inquiry is really about fact-finding in public," she said, adding that there will also be closed-door sessions to find out what is going on in the construction industry. Expert witnesses will also offer advice.

"I think it's both the idea of finding some facts and trying to find some solutions," Maioni said.

Earlier in the day, opposition members questioned the efficacy of the upcoming probe.

"Will it be a real mandate that will shed light on everything?" Parti Quebecois Leader Pauline Marois asked.

"Will the mandate be the same one that has been proposed many times here, in the national assembly?"

Calls for an official probe into the construction industry began in 2009, as reports of rampant corruption began surfacing. Other reports about illegal political contributions from wealthy business people also surfaced in the media and elsewhere.

Charest declined to call an inquiry, and instead implemented 15 policy changes aimed at dealing with the problem.

The earlier changes included the creation of an anti-corruption unit, new reforms on political contributions and changes to the way that municipalities award construction contracts.

With a report from CTV Montreal's Maya Johnson