Choke holds are viable self defense and compliance techniques. They largely are safe and leave no lasting health problems, if done properly. If released when compliance is obtained or the subject becomes unconscious, they simple will wake up with cuffs on.
BJJ should be taught to all police because it teaches these techniques in a way that emphasizes safety. The best possible outcome is that the police obtain control of the subject with minimal injury. Unlike punching, tazer or in extreme cases the use of the police firearm, injury or potential injury is much more substantial.
This tool should not be banned, but focused on for its effectiveness and taught to the police for how to implement and recognize the stages of how the subject will respond to it.