He should have to pay for the pain and suffering he caused since he was unable to be a man and control himself. 10,000 dollar fine plus revoke his driver's license for 1 year and force him to do two months of community service with the humane society fundraisers.
Okay, devil's advocate time:
Any of you ever had to deal with someone's yappy dog for an extended period of time? Not like yap-yap run off back home, but yap yap yap and never shut up? Ever had one that did this even when you were in your own yard? It can drive you to these thoughts. I don't blame the dogs, they're just dogs. The worst ones are almost always the terrified lap dogs that only shake and piss and yap.
My dogs are cool and are people friendly. If they bark at a neighbor or at someone for no reason, I tell them to shut up. It's the people who don't care to leash them and let them come into my yard and bark at me that get me angry.
Even still, he should have to pay for not only what he did, but for being such a coward as to pick on a small dog. I only wish for a moment that the lady had had a Rottweiler lying down in her backseat when he reached in for the smaller dog. He would've had his hand digested. Suitable penalty for the infantile jerk.