Sure. That's what he's good at.
That being said, keep him in jail, or, in my own personal view, hang him. We obviously cannot trust him and must hand him over to God for judgement - which he will eventually run into, whether by our hands or by the natural process of life.
As for repentance, I doubt whether very many people are in enough command of their emotions and actions to truly repent in this life. That's why I believe in Grace. It isn't our efforts to repent that truly matter, it is God's drawing us to repentance that helps us to heal.
But there is a place for corrective therapy - if you don't learn it on Earth, you learn it in Hell.
that's my belief about Hell, at least, that it is a place designed to provide ever harsher correction, correction that may not be possible on Earth.
Finally, C.S. Lewis talked at length about the role the body itself plays in our actions - we know not how much a bad digestion, for instance, can make someone have a bad temper; they may actually in their true selves be quite nice people, and what we see as a bad temper could be endurance stretched beyond human capacity.
So who knows what external things have influenced this man? Brain chemistry, bad childhood, etc. etc. etc. Don't let him go, but that doesn't mean God cannot find means to forgive.
CZAR