You don't, but I do believe in second chances, with ample precautions taken.
Fine, lets put ankle bracelets on them then. Criminals have more rights than the victims.
I'm all for 2nd chances and in many cases 10th and 20th chances.
But not with kids sexual abuse. All the more so for the more serious types of it. There is a range.
I don't know how to filter out the rather rare ones who've genuinely changed. Especially in our crazy society. It's a real challenge. A young shrink could make a name for himself doing it reliably.
Where do you live? We will let him know that he can live peacefully as your neighbor, because you trust him to have changed.