Well, over at thesensibleparty.blogspot.com, Col suggested Crime and Punishment as a topic.
A big and complex one this.
What I would say is there is one thing I like about the US system - their harsher sentences. If you murder someone and there is no doubt you did, then you should not be allowed to be free ever again, after all the person who is dead and everyone close to them can never be the same again.
I suppose it's all a matter of how sure you are that the system works (Very Minority Report-ish eh?)
If you could be 100% sure then I'd put every rapist, murderer and serious drug dealer away for for the term of their life, nothing less would do. What appals me just now is the sentences for people who kill someone will drink driving for example, they are far too lenient.
Also, companies and company directors get off too lightly too.