From Article 9 in the National Collective Agreement FSSS / CSN

9.02  Group leader (Team Leader)
“Person who, under the direction of the service head and while working herself or himself, sees to the training and co-ordination of the work of a group of employees in her/his category.”

9.03 Assistant group leader
“Person who shares the responsibilities of the group leader and replaces the latter during their absence.”

Article 9.02 clearly states that the role of the group leader is to train people and redistribute the work. Their role is not to that of a supervisor. Group leaders do to attend disciplinary meetings between the employer and another employee and they do not take disciplinary action.

If you become aware of a Group Leader or assistant Group Leader performing the task of a supervisor, contact your local union office.

9.04  Both group leader and assistant are selected on a voluntary basis and by seniority.
“The duties of group leaders and assistant group leaders shall be granted according to the criteria provided for the provisions respecting voluntary transfers. However, applications for these duties shall be limited to employees in the category for which such duties are required.”