Part of the nature of this argument is that the criminal justice system exists to "punish" individuals (which I disagree with), and to keep the public safe (which I agree with). Let's examine both of those assumptions. If the criminal justice system exists only to punish individuals and not to attempt to rehabilitate them, then it only functions as a potential deterrent for criminals. Clearly, this deterrent isn't very effective, since people still commit crimes. The criminal justice system should really exist not to punish, but to attempt to rehabilitate individuals to ensure that they are no longer a danger to society. If there is no effort made to make sure criminals don't repeat their criminal behavior, then it certainly fails at its second job, which is to ensure public safety. By focusing on rehabilitation instead of punishment, we will minimize the chances of criminals repeating their criminal behavior once they get out of prison. After all, if we, for example, double sentences for all sex offenders, won't they be just as much of a danger in 10 years as they would in 5, if we don't try to recondition their behavior while they're in prison? If there's no effort made to rehabilitate, then criminals will be just as likely to re-commit crimes when they get out of prison regardless of how long they serve. The only real way to ensure public safety would be to impose a mandatory life sentence to all sex offenders. I'm definitely not trying to say that the goal of the criminal justice system should be only to rehabilitate and not have any element of punishment - I'm saying that if it only exists to punish and doesn't make any attempt at rehabilitation, it's likely that no matter how long a sex offender stays in prison, he or she will be likely to re-commit his or her crime once he or she gets out.

Yes it's impossible to fully rehabilitate everyone, but let's look at the alternative. Let's say we increase sentences for one particular sex offender from 5 years to 15 years. If that's all we do, and we don't have an element of rehabilitation, he's just going to have to wait 3x as long to get out, and we still have no guarantees that he won't do the same thing again. So without rehabilitation in our criminal justice system, you do have to come to the conclusion that sex offenders need to serve life terms. But is that really a good solution? I don't think it is, because besides being tremendously burdensome to taxpayers, we would need to adopt that logic for ALL crimes. If someone robs a convenience store, drives drunk and hits someone, abuses a spouse, traffics illegal drugs, or just about any crime, there's never a guarantee they won't do it again. So if we really aren't interested in trying to prevent criminals from re-committing their crimes, shouldn't all crimes be punishable by life sentences?

An argument might be that giving them rehab doesn't guarantee that they aren’t going to go out and commit the same crime. That’s right, and that's a scary thought, but it's the reality we have to deal with. I don't think we can realistically lock people up for life for committing crimes, so we need to design our criminal justice system in such a way that ensures that the public is as safe as possible. It's not going to be a perfect system, but we can certainly make it better than it is now. This proposal I'm about to make has a lot of flaws, and it's more of a thought experiment than a policy, but ideally, I think the criminal justice system should look like this: Criminals should be sentenced to prison based on the average amount of time it takes to rehabilitate someone who has committed that crime. If, however, that person is deemed to not have been rehabilitated in that amount of time, a jury of peers should be empowered to extend that individual's sentence. Individuals who are deemed an intransigent danger to society should spend life behind bars, in the interest of public safety.