I went back and reread my post and nowhere is there any mention of remorse. Even sociopaths experience the feelings I wrote of. Remorse has nothing to do with it. They'd rather be out of prison than in and sociopaths crave being the center of attention-is gives then validity. You want to punish a sociopath? Send then to Florence. Or Angola. For life.
I have a close family member who is a sociopath, no counselor or therapist can help them. All they do is learn how to be a better sociopath, they are incapable of being an empath and for a good example liken them to a vampire, that only sees humans as a food source. As tough as it was my wife and I broke off all forms of contact two years ago, we should have done it twenty five years ago. As his latest therapist said in our last meet and greet "There are some people that just shouldn't be together." After years of personal therapy due to guilty feelings of inadequate parenting and being assured that it was not my fault I have learned a ton about Narcissists/Sociopaths, etc. Most of us are related to one and all of us have been in contact with one without knowing. One in twenty people are sociopaths, they are usually very charismatic and are excellent sales people. Often highly successful until they either obviously show total lack of regard for others or get arrested. Your friend that couldn't tell the truth if they had to is probably a sociopath.