Incapacitation is the easiest to make the case for societal benefit. If a robber is locked up, he can't rob you. That's incapacitation. Nearly everybody agrees that incapacitation is necessary, even people obsessed with rehabilitation are generally willing to concede that until a dangerous criminal is successfully rehabilitated, he probably needs to be locked up.

Hardly any prisoners are sentenced to rehabilitation, and most justice systems have few means of doing so, so it appears hardly any justice system is based on the notion of locking people up until they are rehabilitated.

(there are some rare exceptions - in Norway the maximum sentence is 21 years except in some particularly serious cases you can be convicted to incarceration for the purpose of protecting society - this punishment is in theory shorter in that you can get out after 10 years, I think, but you won't get out until a parole committee deems that you are no longer a risk).

Furthermore, if justice systems were based on reoffending risks, then sentencing would look very different. Most murderers who commit murders that aren't gang-related, for example, are very low-risk prisoners. Yet no justice system I am aware of takes that into account.

Incapacitation is only one of the reasons we imprison people, albeit the most important reason and the most easily defensible. Murderers who are unlikely to reoffend are still put into prison because our prisons are also for punishing people who do things we think are worthy of punishment. There's no contradiction here, prisons simultaneously serve several purposes.

Indeed, and many of these factors are taken into consideration for the construction of sentences, although often times with different weighting that some people would like.

Point remains that the concern of reoffending is rarely if ever given much actual consideration - reoffending rates shows that the sentencing very clearly does very little to ensure people are locked up until rehabilitated.

you are mixing two separate topics. Concern of reoffending =/= optimizing rehabilitation.

reoffending is rarely if ever given much actual consideration - False, It is usually the #1 consideration, and why courts look at criminal history, risk factors, ect. This doesnt have to be based on rehabilitation, but can be justified simply with a incapacitation rationale.

E.G. You think someone is likely to reoffend so you lock them up longer. not because you think it will offer more rehabilitation, but because it incapacitates them for longer.

3 strikes laws are a classic example of this. You dont give someone a 25 sentence because thats how long it takes to rehabilitate them. you do it because you think they are a serial offender you want to keep off the streets and they are unlikely to be rehabilitated

> False, It is usually the #1 consideration

No, it is not, or the prison system would be structured entirely differently. Courts do not have the power to affect that.

> E.G. You think someone is likely to reoffend so you lock them up longer. not because you think it will offer more rehabilitation, but because it incapacitates them for longer.

The reality is that this is unproductive when it comes to reducing crime.

> 3 strikes laws are a classic example of this. You dont give someone a 25 sentence because thats how long it takes to rehabilitate them. you do it because you think they are a serial offender you want to keep off the streets and they are unlikely to be rehabilitated

The reality is that this too is ineffective at reducing crime.

> "concern of reoffending is rarely if ever given much actual consideration"

Complete bullshit. Concern for somebody reoffending is a major factor in sentencing and in the public's support for the continued existence of the prison system. Examples of sentencing that follow from other principles do not contradict this.

The US prison system is demonstrably awful at reducing reoffending.

Agreed, I think we are saying the same thing. I left out a word

> Incapacitation is the easiest to make the case for societal benefit.

In which case we would not be locking up people for victimless crimes