I agree absolutely horrific thing to do, hopefully some bad karma will be coming their way!!

But I also just have to say, much loved Collie? Then why was it left to go walkies alone, I don't live anywhere near a road, but still wouldn't let my dog take itself out, dog theft just one of the reasons, getting hurt, disturbing neighbours and going onto property where it shouldn't, it makes no sense.
As wicked as this person/s were the little B's, if the dog was with it's owner it would never have even happened. :-( We all know there are evil people out there, we should always protect out loved ones from children to dogs as much as we can.