**********FROM THE COMMENTS: Ask a doctor...
Well I'm not a lawyer, but I worked on the medical side of forensics psychiatry for a while and saw some of Canada's worst criminals.*
Every time I hear one of these guys talk about longer sentences not having an effect I have to wonder what kind of background work they are doing on their clients because I would often review the case sheets from many of the patients.
One thing I noticed was that these guys often had numerous convictions, often very violent, going back several years before they finally got referred to forensic psychiatry.
No one has yet been able to convince me that locking these guys up forever after their first or second violent offence wouldn't have prevented the third fourth, fifth, sixth rape/violence offence that they commited.