If the police do not act, you spur the city to get the police to act. Sue the city. You're absolutely right. The man should deplete his wealth hiring lawyers

If the police do not act, you spur the city to get the police to act. Sue the city. You're absolutely right. The man should deplete his wealth hiring lawyers to navigate the byzantine rules of dysfunctional city bureaucracy. He should dedicate his life to this goal on top of his full-time work. After a few years, some statements will be made and nothing will happen. But at least he took the high road to nowhere.