I don't understand this argument. If you had a reasonable excuse to commit a crime, then you don't have to rehabilitate that person. Rehabilitation is for people who didn't have reasonable excuses for their crimes. Am I missing something?
Please do explain how you can rehabilitate a rapist. Rape is one of the few crimes to not have a single reasonable excuse.
One can steal, murder, or sell drugs out of desperation. Nobody rapes out of desperation, you are inherently and eternally wicked if you are a rapist.