He stared down Quebec's most dangerous gangsters, helped bring an end to a bloody biker war and then built a political career on his law-and-order reputation.

But on Wednesday, Guy Ouellette was arrested, sending shock waves through Quebec's political circles. Quebec's super-cop is now himself a suspect.

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It was not immediately clear why Ouellette was arrested, and he has not yet been charged with a crime. But on the same day as his arrest, the province's anti-corruption unit was carrying out raids as part of an investigation into leaked confidential documents.

For the past 10 years, Ouellette has been a relatively nondescript MNA for the Laval riding of Chomedey, hard-working but rarely in the limelight.

Before entering politics, however, he spent close to three decades in the Sûreté du Québec, much of that going toe-to-toe with biker gangs while they were at the height of their powers.

From Townships boy to biker gangs

Born in the Eastern Townships, Ouellette joined the SQ in 1969 with nothing more than a high-school degree. He worked his way up the ranks and eventually joined the drug squad.

In the early 1990s, Quebec's biker gangs entered into open conflict with each other over control of the drug trade.

With the death toll rising rapidly — it would reach 165 by the time it was over — the province formed an elite anti-gang unit called Wolverine. Ouellette was part of the team.

For the next several years, he shadowed bikers nearly everywhere they went. As Paul Cherry recounts in his book, The Biker Trials: Bringing Down the Hells Angels, Ouellette was often on the same flights and in the same hotels as the suspects he was tracking.

​He wasn't afraid to talk to them directly — once confronting Hells Angel leader Maurice "Mom" Boucher about a stolen briefcase — and earned a measure of their respect.

Police say Maurice "Mom" Boucher was arrested in his cell as part of the operation. (Radio-Canada)

Within the SQ, he was known for his encyclopedic knowledge of the Byzantine biker world — the ever-changing alliances, who was on their way up and who was on their way out.

That made him a favourite Crown witness. His testimony helped put dozens of bikers behind bars, including Boucher, the most notorious of them all.

His evidence was so effective, members of the Hells Angels had a meeting in 1999 in order to come up with ways to discredit him, according to documents released at a 2002 trial.

Life as a back-bencher

He retired from the force in 2001 but continued to testify while also serving as an organized crime expert for Radio-Canada.

When he joined the Liberals in 2007, many political observers believed he was a shoo-in for a cabinet position. Who better to serve as public security minister?

On the campaign trail that year, he joked to a journalist that he could even count on the biker vote.

"They will vote Liberal because they want me in Quebec City and not after them, not testifying against them in court," he said.

Ouellette on the campaign trail in 2007. He was arrested Wednesday. (Paul Chiasson/Canadian Press)

But Ouellette never made the front benches under Jean Charest or Philippe Couillard. Instead he toiled away in the corridors and committee rooms of the National Assembly.

As a member of the public administration committee, he helped organize the testimony last year of former Transport Ministry officials, who told of a culture of intimidation and falsification of documents within the department.

He spoke publicly at the time about the need for a police inquiry and called on the provincial anti-corruption unit to get involved as well.

It was the same anti-corruption unit that, on Wednesday, was conducting raids into leaked documents. Ouellette was arrested as part of that investigation, sources told Radio-Canada.