With the Quebec election campaign focusing in recent days on integrity and corruption, Marois said there was nothing sinister about the PQ's silence on the meeting with the UPAC anti-corruption unit.
Marois told a news conference it was UPAC that asked the party not to talk about a meeting the party has described as informal and centred on party financing.
"My director general told me that UPAC asked him not to talk about this visit," Marois said, adding she was informed by party officials a few days after it happened.
The meeting only came to light late Tuesday through media reports and was quickly confirmed in a PQ statement.
Last September, when Liberal Leader Philippe Couillard was met by the anti-corruption squad a few months after raids at Liberal offices, he held a news conference the same day to clear the air.
"We don't have anything to hide," Marois said. "When UPAC came to the Parti Quebecois, they asked for some information about the way we do financing."
Marois has been attacking the Liberals for several days on integrity issues as her party runs second in various polls.
She said it's unfair to compare the February meeting with the Liberal encounters with UPAC. The anti-corruption force seized documents in the Liberal raids as part of an ongoing corruption investigation.
"I will never accept that we compare the Liberals and the PQ when it comes to financing and granting of contracts," Marois said.
Marois also repeated that UPAC had met with all political parties, but the Coalition for Quebec's Future insists it never had such a meeting.
Issues of ethics, integrity and corruption dominated the campaign trail on Wednesday.
Marois had to backtrack on an error she's repeated in the past few days: that ex-Liberal minister Tony Tomassi is facing criminal charges related to the selling of daycare permits.
After several questions on the matter, Marois conceded that the charges of fraud and breach of trust against Tomassi stem from the use of a credit card provided to him by a now-defunct security company.
Tomassi is one of the examples she has cited in recent days in her attacks on the Liberals' integrity record. In another, Marois has talked about a now abandoned policy by the Liberals to have ministers each raise $100,000 per year in fundraising.
On Wednesday, Coaltion Leader Francois Legault said the PQ had similar fundraising objectives when he was with the sovereigntist party.
Legault spent 11 years at the legislature with the PQ before eventually becoming Coalition leader in 2012. He called the PQ attacks on the Liberals "hypocritical."
"Every year, I had to raise $80,000 because I had been there longer," Legault said. "There was an amount for each riding, each party member ... and when people did not reach their objectives, they were called to the party headquarters."
The PQ denied Legault's claim. Marois said riding associations set goals each year for the amount of money to be raised, but it wasn't a practice that extended to ministers.
Legault also agreed to disclose his personal financial information for 2012, answering Couillard's call this week.
The Liberal leader promised to publish 2012 income-tax returns and other financial details about himself and his wife on his party's website before Thursday's leaders' debate and encouraged his counterparts to do the same.
Couillard called it a question of transparency. Legault relented on Wednesday after appearing hesitant a day earlier.
"In order to have full integrity and show full integrity, I will table in the next few days all my assets and the assets of my wife," Legault said.
For her part, Marois maintained she will not make her and her husband's personal financial information public. She noted her spouse, wealthy businessman Claude Blanchet, has stepped down from any positions he had on boards of directors and his investments are tied up in a blind trust.
Marois repeated that she provides all relevant financial documentation to the province's ethics commissioner.
All three leaders were in Montreal ahead of their second televised debate, which will also feature Francoise David of Quebec solidaire.
Couillard was asked at one event about $428,000 in party financing that still remains unaccounted for.
The PQ filed a complaint about the money with Quebec's electoral office this week.
The figure stems from recently released UPAC court documents describing the search of Liberal offices last July and the companies of ex-party fundraiser Marc Bibeau in November. The documents suggested the Liberals amassed more than $700,000 in contributions, including one event that generated the $428,000.
Couillard said Wednesday there was no record of that amount in the party's books, but he has faith in UPAC to get the bottom of the situation.
"If anybody has done anything wrong, we want to know the truth," Couillard said. "And, by the way, all the 50,000 members of our party want to know the truth and want people to be accountable for that."
Couillard has been under constant attack for integrity issues that surfaced under his predecessor's watch. The PQ attacks have centred on scandals that occurred when Jean Charest was premier.
But the Liberal leader, who is leading in public opinion polls, said he isn't interested in mudslinging. He didn't want to dwell on past anti-corruption moves by his party.
"What I think (of the past) isn't important," Couillard said. "It's what I've done since becoming leader."
Meanwhile, Legault was asked if he thought his party was the cleanest of the bunch.
"What I can say is you cannot have somebody cleaner than me," he replied. "I have no skeletons in my closet."
- with files from Alexandre Robillard, Patrice Bergeron and Martin Ouellet.
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