Quebec's anti-corruption unit last week arrested Guy Ouellette, a former high-profile police officer and sitting member of the Quebec legislature. Some have called it an unprecedented crisis for the National Assembly.

Ouellette has not been charged with a crime and alleges his arrest was a setup designed to intimidate him.

UPAC is Quebec's anti-corruption police force. The government agency is tasked with rooting out corruption, collusion and influence peddling in the awarding of public contracts.

Its representatives tell a much different story about Ouellette's arrest, saying it was part of an investigation into leaked police documents.

These two versions of events have brought up many questions — including which one is closer to the truth.

Who is Guy Ouellette?

Guy Ouellette has been a member of Quebec's legislature for 10 years. He was elected as a Liberal but has been sitting as an independent since his arrest.

He was a high-profile police officer with the Sûreté du Québec and was known for his instrumental role in dismantling Quebec's powerful biker gangs in the late 1990s. His testimony as a Crown witness helped convict the notorious former Hells Angels leader, Maurice "Mom" Boucher.

In the late 1990s, Ouellette testified in a trial that convicted prominent bikers, including Maurice 'Mom' Boucher, shown here. (Radio-Canada)

Ouellette has always been on the backbenches as an MNA. Despite his reputation as a respectable crime fighter, he has never held a cabinet post.

Until his arrest, Ouellette was chair of a parliamentary committee studying a bill that would give UPAC expanded powers, but he wanted to impose certain standards and safeguards.

Ouellette was arrested and his home searched by UPAC on Oct. 25 as part of an investigation into leaked police documents reportedly linked to another investigation looking at provincial Liberal party financing under former premier Jean Charest.

What does Ouellette allege?

In the legislature Tuesday, Ouellette alleged UPAC is framing him.

"In an unprecedented attempt at intimidation, I was the victim of a setup by [UPAC]," he said.

Without giving many details, he suggested the anti-corruption unit was trying to prevent legislators from doing their work. As head of the committee overseeing UPAC, he said he had recently learned of certain "irregularities."

Independent MNA Guy Ouellette walks in to the legislature in Quebec City to make a declaration over his arrest by the anti corruption unit on Oct. 31, 2017. He says he is the victim of a setup by the province's anti-corruption unit. (Jacques Boissinot/Canadian Press)

Ouellette denied the allegations against him.

"Preventing members of the National Assembly from exercising the mandate the population gave them is a very serious attack on the democratic process," he said.

In an interview in the Journal de Montréal earlier this week, former government analyst Annie Trudel alleged Ouellette was arrested because he was about to reveal potentially damaging information — namely, that the anti-corruption unit was involved in collusion itself.

Former government analyst Annie Trudel, shown in a file photo from 2016, says Ouellette was arrested because he was about to reveal UPAC was involved in collusion. (Jacques Boissinot/The Canadian Press)

Trudel described an alleged scheme with Quebec's securities regulator to get companies bidding for public contracts to pay large sums of money to a particular consulting firm to help them qualify to bid. The securities regulator and UPAC deny this.

Why does UPAC exist?

Known by its French acronym, UPAC was formed under Charest in 2011 amid revelations of collusion and corruption in the construction industry and calls for an inquiry. Charest launched the Charbonneau Commission later that year.

UPAC is headed by Robert Lafrenière, a commissioner appointed by the government. It's made up of members from organizations including the Montreal police and Quebec provincial police.

Former Montreal mayor Michael Applebaum was sentenced 12 months in jail and two years probation earlier this year. He was convicted of eight corruption-related charges, including two counts each of fraud on the government, conspiracy to commit fraud on the government, breach of trust and conspiracy to commit breach of trust. (Paul Chiasson/Canadian Press)

The unit was behind the high-profile arrests of former Montreal mayor Michael Applebaum, former Laval mayor Gilles Vaillancourt, and former Liberal deputy premier Nathalie Normandeau. But UPAC has been accused of dragging its feet in other investigations. Opposition parties have suggested its ties to the government are too close.

Who is Robert Lafrenière?

Lafrenière was appointed by former premier Jean Charest. In 2016, current Premier Philippe Couillard renewed his mandate for five more years.

He was previously a deputy minister in Quebec's Public Security Ministry after a long career as a police officer who moved up the ranks within the Sûreté du Québec.

UPAC commissioner Robert Lafrenière spoke in what he called an 'exceptional' news conference earlier this week as he responded to Ouellette's allegations of intimidation. (CBC)

Lafrenière testified in front of the public security committee earlier this year, where he defended the agency's independence and denied investigations are influenced by political meddling. On the topic of leaked police files, Lafrenière told the committee, "I very much hope that we come to a conclusion, and find the bandit who would have done that."

What does UPAC say?

Facing mounting political pressure, UPAC held a press conference Tuesday to address Ouellette's arrest and his allegations against the force. UPAC defended its techniques and the investigation that led to Ouellette's arrest.

"No intimidation was used in this case," said André Boulanger, UPAC's operations director. "I vehemently refute this allegation."

He also denied Ouellette was arrested because he was about to reveal a collusion scheme involving UPAC.

Lafrenière said leaking police documents is an "extremely serious" crime that can sabotage important investigations. He said he is convinced someone will eventually be charged in this case, but did not say if it will be Ouellette.

What's the political reaction?

In the legislature Tuesday, Ouellette had support from many of his political colleagues. House speaker Jacques Chagnon called the situation "indefensible." He also said UPAC should either charge Ouellette with a crime or apologize.

"Police forces must be beholden to responsible politicians and to parliament," Chagnon said. "Otherwise, the risks of a slide into totalitarianism increase greatly."

On Oct. 31, Quebec Premier Philippe Couillard told reporters he believes both Ouellette and UPAC officials have given as much information as they can. He is considering calls for a surveillance committee for more oversight of UPAC. (Jacques Boissinot/Canadian Press)

Earlier this week the government announced the auditor general will look into the allegations of collusion involving UPAC and the securities regulator, and take a fresh look at the bill designed to give UPAC more powers, to ensure it includes a mechanism for accountability and transparency.

Still, Couillard is facing pressure to do more. Some opposition parties have called for a parliamentary commission to allow elected officials to question Ouellette and Lafrenière.

There are also calls for a surveillance committee to provide more oversight of UPAC, which Couillard says he will consider.