You can't "tarnish" someone's reputation if they committed the act in question. Referring to issues of fact are just that: fact.
He admitted to raping a minor, and there is no evidence nor the presupposition of evidence that any type of coercion was involved. Yes, his wife was brutally murdered years previous; I understand that. But human nature is such that one must take responsibility for one's actions.
Can't blame it on Auschwitz (or any type of occupation.) Not on Sharon Tate. He is responsible for his own actions.
Whether or not the young girl tempted/coerced/forced Mr. Polanski to have sex with her doesn't matter: only the act matters.
I find it disheartening that anyone would spend so much time and energy defending someone not worthy of the words. Polanski remains a less-than-stellar human being; whether he was in Auschwitz or not doesn't matter. (As a point of reference, my mom grew up in Norway during the Nazi occupation. Although there were no gas chambers, the Nazis were every bit as ruthless as the mainland counterparts. Still, she found the strength to live her life in a decent way, and NOT injure the lives of others.)
Please use your mind for more constructive things.