Pope sounds like a pretty good guess. He brought Brenda onto the job and then watched her pass him by. She made the short list for Chief of Police, but he didn't. His days as acting Chief of Police are numbered, and he has to feel resentment toward Brenda...maybe he even blames her for his own waning career. If he can discredit her, he might have a shot at keeping the job. He's the only one with a real motive.