Withdrawing a grievance "without prejudice"

The recent decision in Algonquin College v. Ontario Public Service Employees Union, Local 415 considered whether a party can unilaterally withdraw a grievance on a “without prejudice" basis and whether this can make that party liable for costs of the canceled arbitration hearing.  With respect to the first issue, the arbitrator noted that:

While a party filing a grievance can always withdraw it, that party cannot insulate itself from the consequences of that withdrawal simply by asserting that the withdrawal is “without prejudice.”  If the other party agrees to those terms, then the condition comes into play.  But absent such consent, the withdrawal will not be considered as being “without prejudice.”  As a result, the other party could make submissions to a subsequent tribunal regarding the effect of the withdrawal.

Furthermore, the determination regarding the implications of the unilateral withdrawal rests not with the arbitrator who was to hear the grievance, but with the subsequent arbitrator.  That being said, and in order to provide some assistance to the parties, the arbitrator observed that " .... the principles and authorities cited by the Employer are well accepted, rational and worthy of consideration in the parties’ future dealings with each other."

With respect to the claim for costs associated with the cancellation of the arbitrator and the hearing room resulting from the "without prejudice" withdrawal of the grievance that was communicated to the arbitrator and the employer on the eve of the hearing (literally).  The arbitrator, on the basis of the authorities referred to by the Union, denied the request that the union pay the costs of the canceled hearing.