The respondents were promoted to foremen and left the bargaining unit, but later returned to it.
Upon their return, their seniority was calculated under the less generous terms of the new collective agreement rather than the one in effect when they were promoted.
They sought a declaratory judgment in the Superior Court to restore their seniority.
The Supreme Court of Canada held that the Superior Court lacked jurisdiction, as the dispute involved the application and interpretation of the current collective agreement, which falls within the exclusive jurisdiction of a grievance arbitrator.
