blackbike wrote:At zoos we lock up dangerous animals permanently, so why ever let dangerous people free?
Presumably because it's very difficult to know if someone is dangerous. Where should the line be drawn? If everyone with potential to be violent is locked up then there'll be very few people not in prison. If all people who have been violent are locked up then we'll have to build dozens of new prisons.
Oh, and something about redemption and forgiveness (because we are nominally a Christian country).
The problem here (about which we have only the sketchiest information) might be that he was mistakenly deemed to be safe, it could be that he has been let down by the system, it could be that he's pure evil. Or a combination of these things.
Incidentally, we lock up permanently a lot of animal that are not dangerous.