What is the test for liability for sexual harassment?

"[T]he question critical to defendants' liability is not whether plaintiff in fact sexually [65 Cal.App.4th 263] harassed other employees, but whether at the time the decision to terminate his employment was made, defendants, acting in good faith and following an investigation that was appropriate under the circumstances, had reasonable grounds for believing plaintiff had done so." (Cotran v. Rollins Hudig Hall Internat., Inc., supra, 17 Cal.4th at p. 109, 69 Cal.Rptr.2d 900, 948 P.2d 412.)