The appellant union represented employees of Bradco, a unionized company affiliated with Dobbin, a non-unionized company.
Dobbin won a construction contract and hired non-union carpenters.
The union grieved, alleging a breach of the collective agreement's provision against 'double-breasting'.
The arbitrator found the agreement ambiguous, admitted extrinsic evidence (the Harris report), and ruled in the union's favour.
The Supreme Court of Canada held that the arbitrator's decision was protected by a privative clause and should be reviewed on a standard of patent unreasonableness.
The Court concluded that the arbitrator's finding of ambiguity, his admission of extrinsic evidence, and his ultimate interpretation of the collective agreement were not patently unreasonable.
The appeal was allowed and the arbitrator's award restored.
