The comment was meant extremely seriously. It's the old conflict of intent versus outcomes. A murderer certainly intended to kill his target, but such a person isn't necessarily volatile or dangerous. But an impulsive person may well kill a person or three even though he didn't intend to. What's worse, and what should society do about it?

I would, if I were you. Seriously.

From a policy POV, the comment is entirely serious and rational, appropriate.