One union representing some of Antioch’s employees brought an administrative grievance making the same claim as the retired employee plaintiff brought in this later suit–that the City was stinting them on contributions for their benefit to CalPers, This decision holds that the due process limits on collateral estoppel keep it from operating to bar the current suit based on the City-favorable outcome of the earlier union-brought grievance. Most of the current plaintiffs never were members of the union that brought the grievance, and those that had been union members were no longer, having retired before the grievance was brought. They received no notice of the grievance and did not participate in it. The union could not be said to have represented them in the grievance proceedings. As retirees, plaintiffs were not required to exhaust administrative procedures for handling complaints by current employees. Since the alleged stinting on contributions was an on-going monthly occurrence, the plaintiffs’ government claim was timely even if the practice had started long before.