Where there is small crime, there are bigger crimes

I'm with Sir Terry Pratchett on this. A man who would do this to a dog is a man to whom the police should pay attention. One has to wonder, what else is he capable of and what would set him off?

The details are instructive:

At around 3am, he struck the dog around 20 times on the head with a hammer. No explanation was given in court.

When even your defence brief is unwilling to touch one of your actions with a ten foot pole, you know you're a pretty repulsive excuse for a human being.

My inner libertarian rebels against keeping this man in jail because of what he might do; however, I fear that it is a near-inevitability that eventually a human is going to be on the wrong end of his temper.