The main problem as I see it, is what is handed down by the judges. No deterrent at all.
The car parking attendant who is fighting for his life was beaten senseless and ended up with a fractured skull. The perp has been handed a pathetic four and a half year sentence.
That, my friends, is the problem and these scum know they can get away with it, especially since many are under-age and will not receive a prison sentence.