If you do not mind, I will be speaking French.
In all the professions in Quebec, the role of the association is sometimes included with the professional body. So, of course, there are associations. The main role of the professional body is to protect the public. But the association movement is not as developed in Quebec as it is in other provinces or in the United States. Obviously, there are variations from one discipline to another. In psychology, the association movement is less developed than in other jurisdictions or other professions.
So yes, sometimes the Ordre des psychologues du Québec plays an advocacy role, as you say in English.