As I understand it, the reason he fled was because he plead guilty to a lesser charge than rape of a minor, but the Superior Court Judge wasn't going to honor the charge, and was going to sentence him to like 50 years in jail. So he fled the U.S. to France.
Whereupon, he almost imediately began dating 15-year-old Nastassja Kinski. He never expressed remorse, and in fact defended his actions by saying, "Normal love isn't interesting. I assure you that it's incredibly boring."
Normally, the statute of limitations would have expired long ago. But Polanski pled guilty, so the charges stand.
Still, I don't believe a judge will have any interest in putting a famous, wealthy 76-year-old man behind bars, even though it's what the law requires.
Bottom line, though, is that he's a sick pedophile who should have been behind bars this whole time.