Some people can be successfully reformed, most can't or, at least, not to the degree preported here. The problem is, who says what when it comes to a person's reformation. I've known prison inmates to act reformed who immediately returned to their old behavior once clear of the prison walls. And then there's all those "innocent" people who've been locked up. For every 1000 who claim to be innocent there might be, statistacally, one who really is and was wrongfully convicted.
When sifting through all this kind of thing, care must be take so we don't compound an error inversely.