[IluvLucy]

I'd report him anonymously if possible, then watch as often as possible and the next time I saw them out together walk up and tell them how you've admired their little yorkie when you saw them out walking and that you've seen him "walking the dog" alone and look him straight in the eye when you say it.

That way, he KNOWS you've seen him abuse the poor baby and that you're watching. It's kind of a warning without jumping on his head. (That's what I'd want to do)

Then, if you do see him abuse the yorkie again, call the cops or whatever you have to do. If his wife is disabled there should be protection available for her, too. That may be her way out if she's being abused too.