I think it needs to be said that punishment is more about sending a message to future possible-criminals than it is about the guy who actually committed the crime.

I find it much more plausible then your two-month rehab scenario

hmm. I don't think a magical reliable rehab is likely to be discovered any time soon, But given the magical rehab and magical psychologists, I don't think there are further problems in my reasoning for rejecting punishment in that case.

I find the idea that family punishment would be an effective method of law to be somewhat implausible.

oh well.

fake utility function

That could be. I will reconsider most of this stuff.

Talking right at the level of what I feel about this, without trying to rationalize from other preferences, I am slightly averse to punishing criminals, but accept it's necessity in some cases. I am strongly averse to the idea of punishing innocent people, even if it were as effective, I further find it highly unlikely that you could make it effective, but I think that's unrelated to the preferences.