Vaillancourt faces 12 charges including conspiracy, fraud, influence peddling, breach of trust and gangsterism.
He is expected to enter a plea of not guilty.
UPAC a sweep in May.
former director of engineering in Laval, Claude Deguise, former Laval city manager, Claude Asselin, Quebec entrepreneurs Antonio (Tony) Accurso and Mike Mergl, as well as former vice-president of the Dessau engineering firm Rosaire Sauriol.
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