@AC 15:09 re: "Bottom line: criminals should be punished. end. of."
I am glad you do not hold a position of power in my country.
Individuals who violate the law should be evaluated objectively, justly and compassionately by qualified professionals in an attempt to find the best possible way to educate them about the incorrectness of their actions with an eye towards rehabilitation and reentering society as a fully-fledged and trusted citizen with all the rights, privileges, duties and responsibilities held by any citizen.
Individuals who violate the law in a fashion which causes severe harm should be evaluated by both qualified professionals and a jury of their peers in an attempt to classify the severity of their transgression and whether or not it is possible for the individual to be rehabilitated at all.
If it is not possible to rehabilitate the individual – and there are indeed some who cannot be helped – then we should be removing these individuals from society completely. (Lifelong imprisonment.) Here they should be asked to perform some level of productive service for their care, if possible, but overall society should be prepared to bear the burden of maintaining these individuals as the moral and ethical alternative to execution.
At no point should punishment or revenge enter into the deliberations of the treatment of any individual, regardless of the transgression. A civilised society rehabilitates its offenders, it does not punish them.
If you feel the burning need to live in a society focused on punishment, move to the United States of America. At the beginning of 2011, fully 0.73% of the US population was incarcerated, having peaked at 0.754% in 2009. Their prison system is operating at 136% of capacity, housing 23% of the world's prisoners whilst having only 5% of the world's population.
Prisoners released from America's penal system – which does indeed focus on "punishment" versus revenge – have one of the highest reoffence rates in the world. (67% within three years.) This has largely been attributed to the appalling conditions within the prison system that dehumanise prisoners with a focus on punishment rather than rehabilitation.
Even if you have no care for people, or enjoy seeing others "pay" for mistakes, try to grasp the sheer terrible economics of a "punishment"-based system. Human beings are the most capable labour device available, especially for non-repetitive or creative tasks. It is simply bad business to pay for ongoing storage and maintenance of human capital which could otherwise be made profitable with a relatively minor upfront investment.