The Parti Quebecois says there is no evidence that one of Quebec's largest unions ever tried to stop them from demanding an inquiry into the construction industry.

The admission comes after the Charbonneau Inquiry played a wiretapped recording of executives from the Quebec Federation of Labour in 2009.

The recording shows Jean Lavallée, one of the founding members of the union, and president Michel Arsenault were very concerned about then-opposition leader Pauline Marois joining the ADQ in demands that then-premier Jean Charest launch an inquiry into the construction industry.

Fresh from whistleblower Ken Pereira making allegations that union executives were working hand-in-hand with organized crime, Lavallée and Arsenault say an inquiry would be very bad, but it could be stopped.

Arsenault told Lavallée that he would lean on the PQ, and on Marois's husband Claude Blanchet, to stop making demands.

Blanchet was the head of the FTQ Solidarity fund from 1993 to 1997.

"The PQ won't touch that either," said Arsenault.

"Be very careful with that," said Lavallée.

"I'll talk to Pauline," said Arsenault.

"Well, that's it, that's why I wanted to speak to you," said Lavallée.

"I'll talk to her," said Arsenault.

He did say that he never thought there should be an inquiry because widespread corruption did not exist.

"We're not corrupted. It's not because of a few bad apples..." said Lavallée before being interrupted by Justice France Charbonneau.

She demanded to know who were the rotten apples within the union, at which point Lavallée hemmed and hawed, but did not answer.

In 2010, after Arsenault stopped being president of the QFL, the executives joined the chorus of voices calling for an inquiry into the construction industry.

On Tuesday MNA Bernard Drainville said that that if anyone tried to influence the PQ they would have run into a "wall of integrity."

Lavallée's hazy memory

The retired president of the Quebec Federation of Labour, Lavallée, has repeatedly said he doesn't remember much if anything of shady activity taking place during his time in charge of the union.

His memory has frequently been revived by playing recordings of wiretapped conversations, or being presented of photos of himself with major contractors and construction company owners.

On Tuesday Lavallée was prompted to recall how another FTQ president, Michel Arsenault, was offered a $300,000 bribe.

Arsenault has always maintained that nobody attempted to bribe him, and sought affadavits from others to agree with him. However confronted with a wiretap, Lavallée grudgingly admitted that he knew of "an Italian" who had tried to bribe Arsenault.