The choice of members is made by the Governor General in Council. Normally we publish a statement of qualifications. In other words, people who have some knowledge of the area are looked for. There is an interview process, but really that's just to establish competence in the area, and then the Governor General in Council makes decisions. I don't see any impediment for the Governor General in Council deciding on the candidacy of a person who has a labour background.
On October 5th, 2006. See this statement in context.