The complainants, drivers for Dufferin Concrete Products, alleged that their union, Teamsters Local 230, breached its duty of fair representation under section 68 of the Labour Relations Act.
The dispute arose when the employer closed a plant and sought to dovetail the seniority lists of Local 230 and Local 879.
Local 230 initially opposed dovetailing and appealed to the International union.
However, after the International dismissed the appeal and ordered compliance with the Joint Council's decision to dovetail, Local 230 accepted the ruling.
The Board found that Local 230 did not act arbitrarily, discriminatorily, or in bad faith in ultimately accepting the constitutional authority of the International union, and dismissed the complaint.