Re: jail time
the penalty needs to outweigh the potential gain.
make those defrauded/over-charged or whatever whole again plus a percentage (10% - 110%) for harm done. couple that with corporate fines plus potential personal fines and jail time for where-ever the buck stops, be it the CFO who approved the loophole or the board who encouraged "creative accounting"
if the risk far outstrips the reward (and the changes of being caught are significantly higher than today) then they'll play nice (or get even more creative!)