As a believer in causality and a bit of chaos, I think we are 100% product of our surrounding and in that all innocent in all behavior.
In my home country (germany) this is luckily somewhat founded in the legislative system. If I'm not mistaken nobody here will get punished for the sake of revenge, but just to protect society. No matter what you do, you deserve the right to live an OK life. If you are are a danger to society its safety might however stand above your freedom of movement.
It's all about prevention through detention and deterrence. I don't believe much in deterrence, but want to keep up the corrective of society and make no exception for the bad behavior of this guy. If I'd address him directly I would aim for a more diplomatic approach tough. In general I want to express that I'm very much against some of his views and found it difficult to promote his work without distancing myself from his behavior and criticizing it.