Justice Jacques Denis wrote in his ruling that Gabriel Nadeau-Dubois, the charismatic spokesman for the hardline CLASSE group, had advocated anarchy.
The case stems from allegations that Nadeau-Dubois encouraged students to ignore a court injunction obtained by student Jean-Francois Morasse that allowed him to return to class at Laval University in Quebec City.
Nadeau-Dubois said on television on May 13 that it was legitimate for protesters to form picket lines to keep students who had obtained injunctions from getting to their classrooms.
Giuseppe Sciortino, the lawyer for the student leader, pleaded ignorance on behalf of Nadeau-Dubois, saying there was no evidence beyond a reasonable doubt that he had read the injunction.
However, Quebec Superior Court rejected the argument, saying it was clear Nadeau-Dubois was aware of the injuction and used his platform to encourage non-compliance with a court order.
"He encouraged his supporters to block the access of students to their classes, even by picketing, despite the injunction, all to uphold a vote taken by students in favour of the boycott," the judge said of Nadeau-Dubois' comments in the TV interview.
"Saying he's acting out of respect for democracy, Gabriel Nadeau-Dubois encouraged non-compliance with orders issued by the court, including those in favour of plaintiff Morasse. In doing so, he promotes and encourages anarchy rather than civil disobedience."
Nadeau-Dubois, who quit his role as student spokesman last summer, did not testify at the trial.
Nadeau-Dubois faces a maximum of a year in jail when he is sentenced. He could also be sentenced to community work. He did not immediately comment on his conviction but was expected to hold a news conference Friday.
Sentencing arguments begin on Nov. 9.
Nearly one-third of post-secondary students remained away from classrooms during a months-long battle against tuition hikes earlier this year. Streets were snarled by mass demonstrations, some of which turned violent, resulting in mass arrests.
Most students stayed in school, while some were ordered to return by court injunctions. Some protesters blocked attempts to reopen classrooms.
The protests occurred after then-premier Jean Charest announced he would hike tuition fees by $325 a year over five years, which would bring annual fees to about $3,800 in 2017. It later offered to spread the hikes out over seven years — an annual increase of $254 — but that was also rejected.
His government argued that the changes would improve universities, make their funding more sustainable, and still keep tuition lower than most other places in Canada.
But the protesters said the government could have funded universities in a number of other ways, by cutting spending or raising revenue elsewhere. They compared Quebec's tuition rates not to those in other Canadian provinces, but said they were looking to zero-tuition jurisdictions elsewhere in the world as their model.
The increases were shelved by Premier Pauline Marois when her Parti Quebecois took power on Sept. 4. The protests died down.
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