I'm glad everything worked out with you and the police. It was uncalled for but at least they were understanding.
I use prong collars. There are no laws against them here. The only time I can't have one on a dog is at the dog show or trial. I know some people think that they are the worst. They have an opinion. I just continue to train my dogs.
I also have a shelter dog. I wouldn't think of not having it trained. The dog gets excited every time we go out to train.