Interuption

I do apologize normally I would not post anything but craft related items on this post but I am calling for everyone's help. My dog Buddy occasionally slips his collar/leash and when I say occasionally I mean once a month if that, we always walk him on the leash. Sometimes we go out of the house and the door doesn't catch and he comes out etc. . When he does he runs over to the neighbors yard and either my husband or I are quick behind Buddy to get him back. The neighbor today made the comment "If your dog comes over here one more time I will shoot him" and it was said in anger. I am lived beyond belief. We called our local police department there is nothing they can do being Buddy "isn't human". They can only do something if the neighbor was to shoot Buddy. Can you imagine??!??!?! I called the ASPCA and I am waiting to hear back for an investigator. This is just the tip of the ice berg with the issues we have with our neighbor. His dog is continuously coming in our yard several times a day if not more. Does anyone have any other solutions for what I can do? We have invested in an above ground electric fence that we have installed and will begin using. But still how does someone get away with threating a dog? Buddy is not a vicious dog at all.