A decision written by Justice Clarence Thomas said that arbitration is appropriate when a dispute arises after the formation of, or under the terms of the collective bargaining agreement. It would not be correct for an arbitrator to determine questions pertaining to when such an agreement was formed.
The high court affirmed the 9th Circuit Court of Appeals' judgment dismissing Granite Rock's claims against the union to the extent those claims depend on the creation of a new federal common-law tort cause of action, and remanded the case to the district court for further litigation. The court agreed with the employer, Granite Rock Co., that the union interfered with the bargaining agreement.
Justice Sonia Sotomayor filed a partial dissenting opinion in which Justice John Paul Stevens joined.