Collateral estoppel bars the state from prosecuting welfare recipients for welfare fraud when they have already been exonerated in administrative proceedings. Affirming its previous decision in People v. Sims (1982) 32 Cal.3d 468, the court held that Sims had not been either expressly or implicitly overruled by the Legislature, nor had the decision been undermined by subsequent case law. The court remanded, however, for a determination of whether the issues decided at the administrative hearing were identical to those at issue in the criminal proceeding.