On July 4, 2011, the Court of Appeal authorized a class action against the Québec government on behalf of a group of Charlesbourg residents complaining of noise caused by the Laurentian Autoroute.
The Court of Appeal set aside the motion judgment rendered May 17, 2010 by Justice Gilles Blanchet, who had dismissed the motion for authorization to institute the class action.
Petitioners Charles Carrier, Maurice Filion and Réal Maltais complained that traffic on the Laurential Autoroute caused noise pollution. They argued that the noise constitutes an abnormal neighbourhood annoyance within the meaning of article 976 of the Civil Code of Québec.
They tried to convince Transports Québec to build a noise-abatement wall.
The Superior Court ruled that the petitioners could not establish their prima facie right to the conclusions sought because the questions of fact or law raised in their legal action dealt with political decisions of the State.
While the motion judge decided that the members of the group raised identical, similar or related questions of law or fact, he also ruled that the petitioners had not tried to contact all of the residents to see whether they wanted to institute a class action by means of a mandate and power of attorney.
The Attorney General of Québec did not contest that the plaintiffs were capable of representing the class adequately.
The dispute before the Court of Appeal was basically an issue of colour of right: does the State enjoy immunity from prosecution in this particular case under the rule that political decisions are not subject to court review?
The Court of Appeal decided that the motion judge was "[TRANSLATION] overly stringent" when he "[TRANSLATION] prematurely" held that a ground of defence prevailed against allegations that are supposed to be held as proven at the stage of a motion for authorization to institute a class action.
The court stated:
 First, it is important not to confuse the systems inherent to controlling the lawfulness of State decisions with the system of civil liability. Since article 1376 C.C.Q. was adopted, the rules set forth in the Book on Obligations have applied to the State. If the State wants immunity from the civil liability system, it can claim public law immunity to free itself from its obligations, but the burden will then be on the State to prove that this ground of defence applies to its situation:
 […]The civil law principles of civil liability now apply, as a rule, to wrongful acts by such bodies. It therefore belongs to the party which intends to rely on the public law in order to avoid or limit the application of the general rules of civil liability to establish, where the need arises, that there are relevant public law principles that prevail over the civil law rules. 17
 The sufficiency of the evidence is only weighed prima facie at the authorization stage; as a general rule, it would be premature to conclude that the immunity defence applies to the State. It is but one ground of defence among many, and the immunity invoked here by respondent cannot be raised as an objection to admissibility at the authorization stage. Unless it is agreed that the action is frivolous on its face or is certain to fail, that the allegations of fact are insufficient, or that the law invoked is "incontrovertibly" ill founded, it would seem unadvisable under the circumstances to determine the absolute value of this ground of defence at such an early stage of the analysis.
To conclude, the Court of Appeal believed that the motion judge should first have analyzed the sufficiency of the allegations of neighbourhood annoyances and of fault-based liability in order to properly assess the value of the theory posited in the class action before it retained the argument that the State enjoyed immunity from prosecution.
So what now? The Attorney General could seek leave to appeal the matter before the Supreme Court of Canada, or it could get to the merit of the issue by presenting the argument of State immunity once again.
If the Attorney General does not ask the Supreme Court of Canada to intervene, he would be conceding that the State immunity defence is a question of mixed law and fact, which is the same as saying that this type of ground cannot be successfully raised at the authorization stage of a class action.